diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-10-24 06:47:44 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-10-24 06:47:44 +0100 |
commit | 50b825d7e87f4cff7070df6eb26390152bb29537 (patch) | |
tree | ec82aba49ab0c4743266ff37e18c8304a0367d06 /kernel | |
parent | a97a2d4d56ea596871b739d63d41b084733bd9fb (diff) | |
parent | 3f80e08f40cdb308589a49077c87632fa4508b21 (diff) | |
download | linux-stable-50b825d7e87f4cff7070df6eb26390152bb29537.tar.gz linux-stable-50b825d7e87f4cff7070df6eb26390152bb29537.tar.bz2 linux-stable-50b825d7e87f4cff7070df6eb26390152bb29537.zip |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
1) Add VF IPSEC offload support in ixgbe, from Shannon Nelson.
2) Add zero-copy AF_XDP support to i40e, from Björn Töpel.
3) All in-tree drivers are converted to {g,s}et_link_ksettings() so we
can get rid of the {g,s}et_settings ethtool callbacks, from Michal
Kubecek.
4) Add software timestamping to veth driver, from Michael Walle.
5) More work to make packet classifiers and actions lockless, from Vlad
Buslov.
6) Support sticky FDB entries in bridge, from Nikolay Aleksandrov.
7) Add ipv6 version of IP_MULTICAST_ALL sockopt, from Andre Naujoks.
8) Support batching of XDP buffers in vhost_net, from Jason Wang.
9) Add flow dissector BPF hook, from Petar Penkov.
10) i40e vf --> generic iavf conversion, from Jesse Brandeburg.
11) Add NLA_REJECT netlink attribute policy type, to signal when users
provide attributes in situations which don't make sense. From
Johannes Berg.
12) Switch TCP and fair-queue scheduler over to earliest departure time
model. From Eric Dumazet.
13) Improve guest receive performance by doing rx busy polling in tx
path of vhost networking driver, from Tonghao Zhang.
14) Add per-cgroup local storage to bpf
15) Add reference tracking to BPF, from Joe Stringer. The verifier can
now make sure that references taken to objects are properly released
by the program.
16) Support in-place encryption in TLS, from Vakul Garg.
17) Add new taprio packet scheduler, from Vinicius Costa Gomes.
18) Lots of selftests additions, too numerous to mention one by one here
but all of which are very much appreciated.
19) Support offloading of eBPF programs containing BPF to BPF calls in
nfp driver, frm Quentin Monnet.
20) Move dpaa2_ptp driver out of staging, from Yangbo Lu.
21) Lots of u32 classifier cleanups and simplifications, from Al Viro.
22) Add new strict versions of netlink message parsers, and enable them
for some situations. From David Ahern.
23) Evict neighbour entries on carrier down, also from David Ahern.
24) Support BPF sk_msg verdict programs with kTLS, from Daniel Borkmann
and John Fastabend.
25) Add support for filtering route dumps, from David Ahern.
26) New igc Intel driver for 2.5G parts, from Sasha Neftin et al.
27) Allow vxlan enslavement to bridges in mlxsw driver, from Ido
Schimmel.
28) Add queue and stack map types to eBPF, from Mauricio Vasquez B.
29) Add back byte-queue-limit support to r8169, with all the bug fixes
in other areas of the driver it works now! From Florian Westphal and
Heiner Kallweit.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2147 commits)
tcp: add tcp_reset_xmit_timer() helper
qed: Fix static checker warning
Revert "be2net: remove desc field from be_eq_obj"
Revert "net: simplify sock_poll_wait"
net: socionext: Reset tx queue in ndo_stop
net: socionext: Add dummy PHY register read in phy_write()
net: socionext: Stop PHY before resetting netsec
net: stmmac: Set OWN bit for jumbo frames
arm64: dts: stratix10: Support Ethernet Jumbo frame
tls: Add maintainers
net: ethernet: ti: cpsw: unsync mcast entries while switch promisc mode
octeontx2-af: Support for NIXLF's UCAST/PROMISC/ALLMULTI modes
octeontx2-af: Support for setting MAC address
octeontx2-af: Support for changing RSS algorithm
octeontx2-af: NIX Rx flowkey configuration for RSS
octeontx2-af: Install ucast and bcast pkt forwarding rules
octeontx2-af: Add LMAC channel info to NIXLF_ALLOC response
octeontx2-af: NPC MCAM and LDATA extract minimal configuration
octeontx2-af: Enable packet length and csum validation
octeontx2-af: Support for VTAG strip and capture
...
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/bpf/Makefile | 7 | ||||
-rw-r--r-- | kernel/bpf/arraymap.c | 51 | ||||
-rw-r--r-- | kernel/bpf/btf.c | 3 | ||||
-rw-r--r-- | kernel/bpf/cgroup.c | 82 | ||||
-rw-r--r-- | kernel/bpf/core.c | 5 | ||||
-rw-r--r-- | kernel/bpf/hashtab.c | 31 | ||||
-rw-r--r-- | kernel/bpf/helpers.c | 68 | ||||
-rw-r--r-- | kernel/bpf/local_storage.c | 169 | ||||
-rw-r--r-- | kernel/bpf/map_in_map.c | 3 | ||||
-rw-r--r-- | kernel/bpf/offload.c | 18 | ||||
-rw-r--r-- | kernel/bpf/queue_stack_maps.c | 288 | ||||
-rw-r--r-- | kernel/bpf/sockmap.c | 2631 | ||||
-rw-r--r-- | kernel/bpf/stackmap.c | 4 | ||||
-rw-r--r-- | kernel/bpf/syscall.c | 148 | ||||
-rw-r--r-- | kernel/bpf/verifier.c | 973 | ||||
-rw-r--r-- | kernel/bpf/xskmap.c | 2 | ||||
-rw-r--r-- | kernel/umh.c | 16 |
17 files changed, 1498 insertions, 3001 deletions
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 0488b8258321..4c2fa3ac56f6 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -3,7 +3,7 @@ obj-y := core.o obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o -obj-$(CONFIG_BPF_SYSCALL) += local_storage.o +obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o obj-$(CONFIG_BPF_SYSCALL) += disasm.o obj-$(CONFIG_BPF_SYSCALL) += btf.o ifeq ($(CONFIG_NET),y) @@ -13,11 +13,6 @@ ifeq ($(CONFIG_XDP_SOCKETS),y) obj-$(CONFIG_BPF_SYSCALL) += xskmap.o endif obj-$(CONFIG_BPF_SYSCALL) += offload.o -ifeq ($(CONFIG_STREAM_PARSER),y) -ifeq ($(CONFIG_INET),y) -obj-$(CONFIG_BPF_SYSCALL) += sockmap.o -endif -endif endif ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_BPF_SYSCALL) += stackmap.o diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 0c17aab3ce5f..24583da9ffd1 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -358,6 +358,29 @@ static void array_map_seq_show_elem(struct bpf_map *map, void *key, rcu_read_unlock(); } +static void percpu_array_map_seq_show_elem(struct bpf_map *map, void *key, + struct seq_file *m) +{ + struct bpf_array *array = container_of(map, struct bpf_array, map); + u32 index = *(u32 *)key; + void __percpu *pptr; + int cpu; + + rcu_read_lock(); + + seq_printf(m, "%u: {\n", *(u32 *)key); + pptr = array->pptrs[index & array->index_mask]; + for_each_possible_cpu(cpu) { + seq_printf(m, "\tcpu%d: ", cpu); + btf_type_seq_show(map->btf, map->btf_value_type_id, + per_cpu_ptr(pptr, cpu), m); + seq_puts(m, "\n"); + } + seq_puts(m, "}\n"); + + rcu_read_unlock(); +} + static int array_map_check_btf(const struct bpf_map *map, const struct btf_type *key_type, const struct btf_type *value_type) @@ -398,6 +421,7 @@ const struct bpf_map_ops percpu_array_map_ops = { .map_lookup_elem = percpu_array_map_lookup_elem, .map_update_elem = array_map_update_elem, .map_delete_elem = array_map_delete_elem, + .map_seq_show_elem = percpu_array_map_seq_show_elem, .map_check_btf = array_map_check_btf, }; @@ -425,7 +449,7 @@ static void fd_array_map_free(struct bpf_map *map) static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key) { - return NULL; + return ERR_PTR(-EOPNOTSUPP); } /* only called from syscall */ @@ -529,6 +553,29 @@ static void bpf_fd_array_map_clear(struct bpf_map *map) fd_array_map_delete_elem(map, &i); } +static void prog_array_map_seq_show_elem(struct bpf_map *map, void *key, + struct seq_file *m) +{ + void **elem, *ptr; + u32 prog_id; + + rcu_read_lock(); + + elem = array_map_lookup_elem(map, key); + if (elem) { + ptr = READ_ONCE(*elem); + if (ptr) { + seq_printf(m, "%u: ", *(u32 *)key); + prog_id = prog_fd_array_sys_lookup_elem(ptr); + btf_type_seq_show(map->btf, map->btf_value_type_id, + &prog_id, m); + seq_puts(m, "\n"); + } + } + + rcu_read_unlock(); +} + const struct bpf_map_ops prog_array_map_ops = { .map_alloc_check = fd_array_map_alloc_check, .map_alloc = array_map_alloc, @@ -540,7 +587,7 @@ const struct bpf_map_ops prog_array_map_ops = { .map_fd_put_ptr = prog_fd_array_put_ptr, .map_fd_sys_lookup_elem = prog_fd_array_sys_lookup_elem, .map_release_uref = bpf_fd_array_map_clear, - .map_check_btf = map_check_no_btf, + .map_seq_show_elem = prog_array_map_seq_show_elem, }; static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 138f0302692e..378cef70341c 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -2114,6 +2114,9 @@ static int btf_parse_hdr(struct btf_verifier_env *env, void __user *btf_data, hdr = &btf->hdr; + if (hdr->hdr_len != hdr_len) + return -EINVAL; + btf_verifier_log_hdr(env, btf_data_size); if (hdr->magic != BTF_MAGIC) { diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 6a7d931bbc55..9425c2fb872f 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -25,6 +25,7 @@ EXPORT_SYMBOL(cgroup_bpf_enabled_key); */ void cgroup_bpf_put(struct cgroup *cgrp) { + enum bpf_cgroup_storage_type stype; unsigned int type; for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) { @@ -34,8 +35,10 @@ void cgroup_bpf_put(struct cgroup *cgrp) list_for_each_entry_safe(pl, tmp, progs, node) { list_del(&pl->node); bpf_prog_put(pl->prog); - bpf_cgroup_storage_unlink(pl->storage); - bpf_cgroup_storage_free(pl->storage); + for_each_cgroup_storage_type(stype) { + bpf_cgroup_storage_unlink(pl->storage[stype]); + bpf_cgroup_storage_free(pl->storage[stype]); + } kfree(pl); static_branch_dec(&cgroup_bpf_enabled_key); } @@ -97,6 +100,7 @@ static int compute_effective_progs(struct cgroup *cgrp, enum bpf_attach_type type, struct bpf_prog_array __rcu **array) { + enum bpf_cgroup_storage_type stype; struct bpf_prog_array *progs; struct bpf_prog_list *pl; struct cgroup *p = cgrp; @@ -125,7 +129,9 @@ static int compute_effective_progs(struct cgroup *cgrp, continue; progs->items[cnt].prog = pl->prog; - progs->items[cnt].cgroup_storage = pl->storage; + for_each_cgroup_storage_type(stype) + progs->items[cnt].cgroup_storage[stype] = + pl->storage[stype]; cnt++; } } while ((p = cgroup_parent(p))); @@ -232,7 +238,9 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, { struct list_head *progs = &cgrp->bpf.progs[type]; struct bpf_prog *old_prog = NULL; - struct bpf_cgroup_storage *storage, *old_storage = NULL; + struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE], + *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {NULL}; + enum bpf_cgroup_storage_type stype; struct bpf_prog_list *pl; bool pl_was_allocated; int err; @@ -254,34 +262,44 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, if (prog_list_length(progs) >= BPF_CGROUP_MAX_PROGS) return -E2BIG; - storage = bpf_cgroup_storage_alloc(prog); - if (IS_ERR(storage)) - return -ENOMEM; + for_each_cgroup_storage_type(stype) { + storage[stype] = bpf_cgroup_storage_alloc(prog, stype); + if (IS_ERR(storage[stype])) { + storage[stype] = NULL; + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); + return -ENOMEM; + } + } if (flags & BPF_F_ALLOW_MULTI) { list_for_each_entry(pl, progs, node) { if (pl->prog == prog) { /* disallow attaching the same prog twice */ - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return -EINVAL; } } pl = kmalloc(sizeof(*pl), GFP_KERNEL); if (!pl) { - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return -ENOMEM; } pl_was_allocated = true; pl->prog = prog; - pl->storage = storage; + for_each_cgroup_storage_type(stype) + pl->storage[stype] = storage[stype]; list_add_tail(&pl->node, progs); } else { if (list_empty(progs)) { pl = kmalloc(sizeof(*pl), GFP_KERNEL); if (!pl) { - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return -ENOMEM; } pl_was_allocated = true; @@ -289,12 +307,15 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, } else { pl = list_first_entry(progs, typeof(*pl), node); old_prog = pl->prog; - old_storage = pl->storage; - bpf_cgroup_storage_unlink(old_storage); + for_each_cgroup_storage_type(stype) { + old_storage[stype] = pl->storage[stype]; + bpf_cgroup_storage_unlink(old_storage[stype]); + } pl_was_allocated = false; } pl->prog = prog; - pl->storage = storage; + for_each_cgroup_storage_type(stype) + pl->storage[stype] = storage[stype]; } cgrp->bpf.flags[type] = flags; @@ -304,21 +325,27 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, goto cleanup; static_branch_inc(&cgroup_bpf_enabled_key); - if (old_storage) - bpf_cgroup_storage_free(old_storage); + for_each_cgroup_storage_type(stype) { + if (!old_storage[stype]) + continue; + bpf_cgroup_storage_free(old_storage[stype]); + } if (old_prog) { bpf_prog_put(old_prog); static_branch_dec(&cgroup_bpf_enabled_key); } - bpf_cgroup_storage_link(storage, cgrp, type); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_link(storage[stype], cgrp, type); return 0; cleanup: /* and cleanup the prog list */ pl->prog = old_prog; - bpf_cgroup_storage_free(pl->storage); - pl->storage = old_storage; - bpf_cgroup_storage_link(old_storage, cgrp, type); + for_each_cgroup_storage_type(stype) { + bpf_cgroup_storage_free(pl->storage[stype]); + pl->storage[stype] = old_storage[stype]; + bpf_cgroup_storage_link(old_storage[stype], cgrp, type); + } if (pl_was_allocated) { list_del(&pl->node); kfree(pl); @@ -339,6 +366,7 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_attach_type type, u32 unused_flags) { struct list_head *progs = &cgrp->bpf.progs[type]; + enum bpf_cgroup_storage_type stype; u32 flags = cgrp->bpf.flags[type]; struct bpf_prog *old_prog = NULL; struct bpf_prog_list *pl; @@ -385,8 +413,10 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog, /* now can actually delete it from this cgroup list */ list_del(&pl->node); - bpf_cgroup_storage_unlink(pl->storage); - bpf_cgroup_storage_free(pl->storage); + for_each_cgroup_storage_type(stype) { + bpf_cgroup_storage_unlink(pl->storage[stype]); + bpf_cgroup_storage_free(pl->storage[stype]); + } kfree(pl); if (list_empty(progs)) /* last program was detached, reset flags to zero */ @@ -523,6 +553,7 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk, { unsigned int offset = skb->data - skb_network_header(skb); struct sock *save_sk; + void *saved_data_end; struct cgroup *cgrp; int ret; @@ -536,8 +567,13 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk, save_sk = skb->sk; skb->sk = sk; __skb_push(skb, offset); + + /* compute pointers for the bpf prog */ + bpf_compute_and_save_data_end(skb, &saved_data_end); + ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], skb, bpf_prog_run_save_cb); + bpf_restore_data_end(skb, saved_data_end); __skb_pull(skb, offset); skb->sk = save_sk; return ret == 1 ? 0 : -EPERM; @@ -677,6 +713,8 @@ cgroup_dev_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_uid_gid_proto; case BPF_FUNC_get_local_storage: return &bpf_get_local_storage_proto; + case BPF_FUNC_get_current_cgroup_id: + return &bpf_get_current_cgroup_id_proto; case BPF_FUNC_trace_printk: if (capable(CAP_SYS_ADMIN)) return bpf_get_trace_printk_proto(); diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 3f5bf1af0826..7c7eeea8cffc 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1783,6 +1783,9 @@ BPF_CALL_0(bpf_user_rnd_u32) const struct bpf_func_proto bpf_map_lookup_elem_proto __weak; const struct bpf_func_proto bpf_map_update_elem_proto __weak; const struct bpf_func_proto bpf_map_delete_elem_proto __weak; +const struct bpf_func_proto bpf_map_push_elem_proto __weak; +const struct bpf_func_proto bpf_map_pop_elem_proto __weak; +const struct bpf_func_proto bpf_map_peek_elem_proto __weak; const struct bpf_func_proto bpf_get_prandom_u32_proto __weak; const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak; @@ -1792,8 +1795,6 @@ const struct bpf_func_proto bpf_ktime_get_ns_proto __weak; const struct bpf_func_proto bpf_get_current_pid_tgid_proto __weak; const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak; const struct bpf_func_proto bpf_get_current_comm_proto __weak; -const struct bpf_func_proto bpf_sock_map_update_proto __weak; -const struct bpf_func_proto bpf_sock_hash_update_proto __weak; const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak; const struct bpf_func_proto bpf_get_local_storage_proto __weak; diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 03cc59ee9c95..2c1790288138 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -1285,6 +1285,35 @@ int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value, return ret; } +static void htab_percpu_map_seq_show_elem(struct bpf_map *map, void *key, + struct seq_file *m) +{ + struct htab_elem *l; + void __percpu *pptr; + int cpu; + + rcu_read_lock(); + + l = __htab_map_lookup_elem(map, key); + if (!l) { + rcu_read_unlock(); + return; + } + + btf_type_seq_show(map->btf, map->btf_key_type_id, key, m); + seq_puts(m, ": {\n"); + pptr = htab_elem_get_ptr(l, map->key_size); + for_each_possible_cpu(cpu) { + seq_printf(m, "\tcpu%d: ", cpu); + btf_type_seq_show(map->btf, map->btf_value_type_id, + per_cpu_ptr(pptr, cpu), m); + seq_puts(m, "\n"); + } + seq_puts(m, "}\n"); + + rcu_read_unlock(); +} + const struct bpf_map_ops htab_percpu_map_ops = { .map_alloc_check = htab_map_alloc_check, .map_alloc = htab_map_alloc, @@ -1293,6 +1322,7 @@ const struct bpf_map_ops htab_percpu_map_ops = { .map_lookup_elem = htab_percpu_map_lookup_elem, .map_update_elem = htab_percpu_map_update_elem, .map_delete_elem = htab_map_delete_elem, + .map_seq_show_elem = htab_percpu_map_seq_show_elem, }; const struct bpf_map_ops htab_lru_percpu_map_ops = { @@ -1303,6 +1333,7 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = { .map_lookup_elem = htab_lru_percpu_map_lookup_elem, .map_update_elem = htab_lru_percpu_map_update_elem, .map_delete_elem = htab_lru_map_delete_elem, + .map_seq_show_elem = htab_percpu_map_seq_show_elem, }; static int fd_htab_map_alloc_check(union bpf_attr *attr) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 1991466b8327..ab0d5e3f9892 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -76,6 +76,49 @@ const struct bpf_func_proto bpf_map_delete_elem_proto = { .arg2_type = ARG_PTR_TO_MAP_KEY, }; +BPF_CALL_3(bpf_map_push_elem, struct bpf_map *, map, void *, value, u64, flags) +{ + return map->ops->map_push_elem(map, value, flags); +} + +const struct bpf_func_proto bpf_map_push_elem_proto = { + .func = bpf_map_push_elem, + .gpl_only = false, + .pkt_access = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_MAP_VALUE, + .arg3_type = ARG_ANYTHING, +}; + +BPF_CALL_2(bpf_map_pop_elem, struct bpf_map *, map, void *, value) +{ + return map->ops->map_pop_elem(map, value); +} + +const struct bpf_func_proto bpf_map_pop_elem_proto = { + .func = bpf_map_pop_elem, + .gpl_only = false, + .pkt_access = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_UNINIT_MAP_VALUE, +}; + +BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value) +{ + return map->ops->map_peek_elem(map, value); +} + +const struct bpf_func_proto bpf_map_peek_elem_proto = { + .func = bpf_map_pop_elem, + .gpl_only = false, + .pkt_access = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_UNINIT_MAP_VALUE, +}; + const struct bpf_func_proto bpf_get_prandom_u32_proto = { .func = bpf_user_rnd_u32, .gpl_only = false, @@ -194,16 +237,28 @@ const struct bpf_func_proto bpf_get_current_cgroup_id_proto = { .ret_type = RET_INTEGER, }; -DECLARE_PER_CPU(void*, bpf_cgroup_storage); +#ifdef CONFIG_CGROUP_BPF +DECLARE_PER_CPU(struct bpf_cgroup_storage*, + bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]); BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags) { - /* map and flags arguments are not used now, - * but provide an ability to extend the API - * for other types of local storages. - * verifier checks that their values are correct. + /* flags argument is not used now, + * but provides an ability to extend the API. + * verifier checks that its value is correct. */ - return (unsigned long) this_cpu_read(bpf_cgroup_storage); + enum bpf_cgroup_storage_type stype = cgroup_storage_type(map); + struct bpf_cgroup_storage *storage; + void *ptr; + + storage = this_cpu_read(bpf_cgroup_storage[stype]); + + if (stype == BPF_CGROUP_STORAGE_SHARED) + ptr = &READ_ONCE(storage->buf)->data[0]; + else + ptr = this_cpu_ptr(storage->percpu_buf); + + return (unsigned long)ptr; } const struct bpf_func_proto bpf_get_local_storage_proto = { @@ -214,3 +269,4 @@ const struct bpf_func_proto bpf_get_local_storage_proto = { .arg2_type = ARG_ANYTHING, }; #endif +#endif diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index 830d7f095748..c97a8f968638 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -7,7 +7,8 @@ #include <linux/rbtree.h> #include <linux/slab.h> -DEFINE_PER_CPU(void*, bpf_cgroup_storage); +DEFINE_PER_CPU(struct bpf_cgroup_storage*, + bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]); #ifdef CONFIG_CGROUP_BPF @@ -151,6 +152,71 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *_key, return 0; } +int bpf_percpu_cgroup_storage_copy(struct bpf_map *_map, void *_key, + void *value) +{ + struct bpf_cgroup_storage_map *map = map_to_storage(_map); + struct bpf_cgroup_storage_key *key = _key; + struct bpf_cgroup_storage *storage; + int cpu, off = 0; + u32 size; + + rcu_read_lock(); + storage = cgroup_storage_lookup(map, key, false); + if (!storage) { + rcu_read_unlock(); + return -ENOENT; + } + + /* per_cpu areas are zero-filled and bpf programs can only + * access 'value_size' of them, so copying rounded areas + * will not leak any kernel data + */ + size = round_up(_map->value_size, 8); + for_each_possible_cpu(cpu) { + bpf_long_memcpy(value + off, + per_cpu_ptr(storage->percpu_buf, cpu), size); + off += size; + } + rcu_read_unlock(); + return 0; +} + +int bpf_percpu_cgroup_storage_update(struct bpf_map *_map, void *_key, + void *value, u64 map_flags) +{ + struct bpf_cgroup_storage_map *map = map_to_storage(_map); + struct bpf_cgroup_storage_key *key = _key; + struct bpf_cgroup_storage *storage; + int cpu, off = 0; + u32 size; + + if (map_flags != BPF_ANY && map_flags != BPF_EXIST) + return -EINVAL; + + rcu_read_lock(); + storage = cgroup_storage_lookup(map, key, false); + if (!storage) { + rcu_read_unlock(); + return -ENOENT; + } + + /* the user space will provide round_up(value_size, 8) bytes that + * will be copied into per-cpu area. bpf programs can only access + * value_size of it. During lookup the same extra bytes will be + * returned or zeros which were zero-filled by percpu_alloc, + * so no kernel data leaks possible + */ + size = round_up(_map->value_size, 8); + for_each_possible_cpu(cpu) { + bpf_long_memcpy(per_cpu_ptr(storage->percpu_buf, cpu), + value + off, size); + off += size; + } + rcu_read_unlock(); + return 0; +} + static int cgroup_storage_get_next_key(struct bpf_map *_map, void *_key, void *_next_key) { @@ -254,6 +320,7 @@ const struct bpf_map_ops cgroup_storage_map_ops = { int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map) { + enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map); struct bpf_cgroup_storage_map *map = map_to_storage(_map); int ret = -EBUSY; @@ -261,11 +328,12 @@ int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map) if (map->prog && map->prog != prog) goto unlock; - if (prog->aux->cgroup_storage && prog->aux->cgroup_storage != _map) + if (prog->aux->cgroup_storage[stype] && + prog->aux->cgroup_storage[stype] != _map) goto unlock; map->prog = prog; - prog->aux->cgroup_storage = _map; + prog->aux->cgroup_storage[stype] = _map; ret = 0; unlock: spin_unlock_bh(&map->lock); @@ -275,70 +343,117 @@ unlock: void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *_map) { + enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map); struct bpf_cgroup_storage_map *map = map_to_storage(_map); spin_lock_bh(&map->lock); if (map->prog == prog) { - WARN_ON(prog->aux->cgroup_storage != _map); + WARN_ON(prog->aux->cgroup_storage[stype] != _map); map->prog = NULL; - prog->aux->cgroup_storage = NULL; + prog->aux->cgroup_storage[stype] = NULL; } spin_unlock_bh(&map->lock); } -struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog) +static size_t bpf_cgroup_storage_calculate_size(struct bpf_map *map, u32 *pages) +{ + size_t size; + + if (cgroup_storage_type(map) == BPF_CGROUP_STORAGE_SHARED) { + size = sizeof(struct bpf_storage_buffer) + map->value_size; + *pages = round_up(sizeof(struct bpf_cgroup_storage) + size, + PAGE_SIZE) >> PAGE_SHIFT; + } else { + size = map->value_size; + *pages = round_up(round_up(size, 8) * num_possible_cpus(), + PAGE_SIZE) >> PAGE_SHIFT; + } + + return size; +} + +struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog, + enum bpf_cgroup_storage_type stype) { struct bpf_cgroup_storage *storage; struct bpf_map *map; + gfp_t flags; + size_t size; u32 pages; - map = prog->aux->cgroup_storage; + map = prog->aux->cgroup_storage[stype]; if (!map) return NULL; - pages = round_up(sizeof(struct bpf_cgroup_storage) + - sizeof(struct bpf_storage_buffer) + - map->value_size, PAGE_SIZE) >> PAGE_SHIFT; + size = bpf_cgroup_storage_calculate_size(map, &pages); + if (bpf_map_charge_memlock(map, pages)) return ERR_PTR(-EPERM); storage = kmalloc_node(sizeof(struct bpf_cgroup_storage), __GFP_ZERO | GFP_USER, map->numa_node); - if (!storage) { - bpf_map_uncharge_memlock(map, pages); - return ERR_PTR(-ENOMEM); - } + if (!storage) + goto enomem; - storage->buf = kmalloc_node(sizeof(struct bpf_storage_buffer) + - map->value_size, __GFP_ZERO | GFP_USER, - map->numa_node); - if (!storage->buf) { - bpf_map_uncharge_memlock(map, pages); - kfree(storage); - return ERR_PTR(-ENOMEM); + flags = __GFP_ZERO | GFP_USER; + + if (stype == BPF_CGROUP_STORAGE_SHARED) { + storage->buf = kmalloc_node(size, flags, map->numa_node); + if (!storage->buf) + goto enomem; + } else { + storage->percpu_buf = __alloc_percpu_gfp(size, 8, flags); + if (!storage->percpu_buf) + goto enomem; } storage->map = (struct bpf_cgroup_storage_map *)map; return storage; + +enomem: + bpf_map_uncharge_memlock(map, pages); + kfree(storage); + return ERR_PTR(-ENOMEM); +} + +static void free_shared_cgroup_storage_rcu(struct rcu_head *rcu) +{ + struct bpf_cgroup_storage *storage = + container_of(rcu, struct bpf_cgroup_storage, rcu); + + kfree(storage->buf); + kfree(storage); +} + +static void free_percpu_cgroup_storage_rcu(struct rcu_head *rcu) +{ + struct bpf_cgroup_storage *storage = + container_of(rcu, struct bpf_cgroup_storage, rcu); + + free_percpu(storage->percpu_buf); + kfree(storage); } void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage) { - u32 pages; + enum bpf_cgroup_storage_type stype; struct bpf_map *map; + u32 pages; if (!storage) return; map = &storage->map->map; - pages = round_up(sizeof(struct bpf_cgroup_storage) + - sizeof(struct bpf_storage_buffer) + - map->value_size, PAGE_SIZE) >> PAGE_SHIFT; + + bpf_cgroup_storage_calculate_size(map, &pages); bpf_map_uncharge_memlock(map, pages); - kfree_rcu(storage->buf, rcu); - kfree_rcu(storage, rcu); + stype = cgroup_storage_type(map); + if (stype == BPF_CGROUP_STORAGE_SHARED) + call_rcu(&storage->rcu, free_shared_cgroup_storage_rcu); + else + call_rcu(&storage->rcu, free_percpu_cgroup_storage_rcu); } void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage, diff --git a/kernel/bpf/map_in_map.c b/kernel/bpf/map_in_map.c index 3bfbf4464416..99d243e1ad6e 100644 --- a/kernel/bpf/map_in_map.c +++ b/kernel/bpf/map_in_map.c @@ -24,7 +24,8 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) * in the verifier is not enough. */ if (inner_map->map_type == BPF_MAP_TYPE_PROG_ARRAY || - inner_map->map_type == BPF_MAP_TYPE_CGROUP_STORAGE) { + inner_map->map_type == BPF_MAP_TYPE_CGROUP_STORAGE || + inner_map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { fdput(f); return ERR_PTR(-ENOTSUPP); } diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c index 177a52436394..8e93c47f0779 100644 --- a/kernel/bpf/offload.c +++ b/kernel/bpf/offload.c @@ -172,6 +172,24 @@ int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, return ret; } +int bpf_prog_offload_finalize(struct bpf_verifier_env *env) +{ + struct bpf_prog_offload *offload; + int ret = -ENODEV; + + down_read(&bpf_devs_lock); + offload = env->prog->aux->offload; + if (offload) { + if (offload->dev_ops->finalize) + ret = offload->dev_ops->finalize(env); + else + ret = 0; + } + up_read(&bpf_devs_lock); + + return ret; +} + static void __bpf_prog_offload_destroy(struct bpf_prog *prog) { struct bpf_prog_offload *offload = prog->aux->offload; diff --git a/kernel/bpf/queue_stack_maps.c b/kernel/bpf/queue_stack_maps.c new file mode 100644 index 000000000000..12a93fb37449 --- /dev/null +++ b/kernel/bpf/queue_stack_maps.c @@ -0,0 +1,288 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * queue_stack_maps.c: BPF queue and stack maps + * + * Copyright (c) 2018 Politecnico di Torino + */ +#include <linux/bpf.h> +#include <linux/list.h> +#include <linux/slab.h> +#include "percpu_freelist.h" + +#define QUEUE_STACK_CREATE_FLAG_MASK \ + (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY) + + +struct bpf_queue_stack { + struct bpf_map map; + raw_spinlock_t lock; + u32 head, tail; + u32 size; /* max_entries + 1 */ + + char elements[0] __aligned(8); +}; + +static struct bpf_queue_stack *bpf_queue_stack(struct bpf_map *map) +{ + return container_of(map, struct bpf_queue_stack, map); +} + +static bool queue_stack_map_is_empty(struct bpf_queue_stack *qs) +{ + return qs->head == qs->tail; +} + +static bool queue_stack_map_is_full(struct bpf_queue_stack *qs) +{ + u32 head = qs->head + 1; + + if (unlikely(head >= qs->size)) + head = 0; + + return head == qs->tail; +} + +/* Called from syscall */ +static int queue_stack_map_alloc_check(union bpf_attr *attr) +{ + /* check sanity of attributes */ + if (attr->max_entries == 0 || attr->key_size != 0 || + attr->map_flags & ~QUEUE_STACK_CREATE_FLAG_MASK) + return -EINVAL; + + if (attr->value_size > KMALLOC_MAX_SIZE) + /* if value_size is bigger, the user space won't be able to + * access the elements. + */ + return -E2BIG; + + return 0; +} + +static struct bpf_map *queue_stack_map_alloc(union bpf_attr *attr) +{ + int ret, numa_node = bpf_map_attr_numa_node(attr); + struct bpf_queue_stack *qs; + u32 size, value_size; + u64 queue_size, cost; + + size = attr->max_entries + 1; + value_size = attr->value_size; + + queue_size = sizeof(*qs) + (u64) value_size * size; + + cost = queue_size; + if (cost >= U32_MAX - PAGE_SIZE) + return ERR_PTR(-E2BIG); + + cost = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT; + + ret = bpf_map_precharge_memlock(cost); + if (ret < 0) + return ERR_PTR(ret); + + qs = bpf_map_area_alloc(queue_size, numa_node); + if (!qs) + return ERR_PTR(-ENOMEM); + + memset(qs, 0, sizeof(*qs)); + + bpf_map_init_from_attr(&qs->map, attr); + + qs->map.pages = cost; + qs->size = size; + + raw_spin_lock_init(&qs->lock); + + return &qs->map; +} + +/* Called when map->refcnt goes to zero, either from workqueue or from syscall */ +static void queue_stack_map_free(struct bpf_map *map) +{ + struct bpf_queue_stack *qs = bpf_queue_stack(map); + + /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0, + * so the programs (can be more than one that used this map) were + * disconnected from events. Wait for outstanding critical sections in + * these programs to complete + */ + synchronize_rcu(); + + bpf_map_area_free(qs); +} + +static int __queue_map_get(struct bpf_map *map, void *value, bool delete) +{ + struct bpf_queue_stack *qs = bpf_queue_stack(map); + unsigned long flags; + int err = 0; + void *ptr; + + raw_spin_lock_irqsave(&qs->lock, flags); + + if (queue_stack_map_is_empty(qs)) { + err = -ENOENT; + goto out; + } + + ptr = &qs->elements[qs->tail * qs->map.value_size]; + memcpy(value, ptr, qs->map.value_size); + + if (delete) { + if (unlikely(++qs->tail >= qs->size)) + qs->tail = 0; + } + +out: + raw_spin_unlock_irqrestore(&qs->lock, flags); + return err; +} + + +static int __stack_map_get(struct bpf_map *map, void *value, bool delete) +{ + struct bpf_queue_stack *qs = bpf_queue_stack(map); + unsigned long flags; + int err = 0; + void *ptr; + u32 index; + + raw_spin_lock_irqsave(&qs->lock, flags); + + if (queue_stack_map_is_empty(qs)) { + err = -ENOENT; + goto out; + } + + index = qs->head - 1; + if (unlikely(index >= qs->size)) + index = qs->size - 1; + + ptr = &qs->elements[index * qs->map.value_size]; + memcpy(value, ptr, qs->map.value_size); + + if (delete) + qs->head = index; + +out: + raw_spin_unlock_irqrestore(&qs->lock, flags); + return err; +} + +/* Called from syscall or from eBPF program */ +static int queue_map_peek_elem(struct bpf_map *map, void *value) +{ + return __queue_map_get(map, value, false); +} + +/* Called from syscall or from eBPF program */ +static int stack_map_peek_elem(struct bpf_map *map, void *value) +{ + return __stack_map_get(map, value, false); +} + +/* Called from syscall or from eBPF program */ +static int queue_map_pop_elem(struct bpf_map *map, void *value) +{ + return __queue_map_get(map, value, true); +} + +/* Called from syscall or from eBPF program */ +static int stack_map_pop_elem(struct bpf_map *map, void *value) +{ + return __stack_map_get(map, value, true); +} + +/* Called from syscall or from eBPF program */ +static int queue_stack_map_push_elem(struct bpf_map *map, void *value, + u64 flags) +{ + struct bpf_queue_stack *qs = bpf_queue_stack(map); + unsigned long irq_flags; + int err = 0; + void *dst; + + /* BPF_EXIST is used to force making room for a new element in case the + * map is full + */ + bool replace = (flags & BPF_EXIST); + + /* Check supported flags for queue and stack maps */ + if (flags & BPF_NOEXIST || flags > BPF_EXIST) + return -EINVAL; + + raw_spin_lock_irqsave(&qs->lock, irq_flags); + + if (queue_stack_map_is_full(qs)) { + if (!replace) { + err = -E2BIG; + goto out; + } + /* advance tail pointer to overwrite oldest element */ + if (unlikely(++qs->tail >= qs->size)) + qs->tail = 0; + } + + dst = &qs->elements[qs->head * qs->map.value_size]; + memcpy(dst, value, qs->map.value_size); + + if (unlikely(++qs->head >= qs->size)) + qs->head = 0; + +out: + raw_spin_unlock_irqrestore(&qs->lock, irq_flags); + return err; +} + +/* Called from syscall or from eBPF program */ +static void *queue_stack_map_lookup_elem(struct bpf_map *map, void *key) +{ + return NULL; +} + +/* Called from syscall or from eBPF program */ +static int queue_stack_map_update_elem(struct bpf_map *map, void *key, + void *value, u64 flags) +{ + return -EINVAL; +} + +/* Called from syscall or from eBPF program */ +static int queue_stack_map_delete_elem(struct bpf_map *map, void *key) +{ + return -EINVAL; +} + +/* Called from syscall */ +static int queue_stack_map_get_next_key(struct bpf_map *map, void *key, + void *next_key) +{ + return -EINVAL; +} + +const struct bpf_map_ops queue_map_ops = { + .map_alloc_check = queue_stack_map_alloc_check, + .map_alloc = queue_stack_map_alloc, + .map_free = queue_stack_map_free, + .map_lookup_elem = queue_stack_map_lookup_elem, + .map_update_elem = queue_stack_map_update_elem, + .map_delete_elem = queue_stack_map_delete_elem, + .map_push_elem = queue_stack_map_push_elem, + .map_pop_elem = queue_map_pop_elem, + .map_peek_elem = queue_map_peek_elem, + .map_get_next_key = queue_stack_map_get_next_key, +}; + +const struct bpf_map_ops stack_map_ops = { + .map_alloc_check = queue_stack_map_alloc_check, + .map_alloc = queue_stack_map_alloc, + .map_free = queue_stack_map_free, + .map_lookup_elem = queue_stack_map_lookup_elem, + .map_update_elem = queue_stack_map_update_elem, + .map_delete_elem = queue_stack_map_delete_elem, + .map_push_elem = queue_stack_map_push_elem, + .map_pop_elem = stack_map_pop_elem, + .map_peek_elem = stack_map_peek_elem, + .map_get_next_key = queue_stack_map_get_next_key, +}; diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c deleted file mode 100644 index 0a0f2ec75370..000000000000 --- a/kernel/bpf/sockmap.c +++ /dev/null @@ -1,2631 +0,0 @@ -/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General Public - * License as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - */ - -/* A BPF sock_map is used to store sock objects. This is primarly used - * for doing socket redirect with BPF helper routines. - * - * A sock map may have BPF programs attached to it, currently a program - * used to parse packets and a program to provide a verdict and redirect - * decision on the packet are supported. Any programs attached to a sock - * map are inherited by sock objects when they are added to the map. If - * no BPF programs are attached the sock object may only be used for sock - * redirect. - * - * A sock object may be in multiple maps, but can only inherit a single - * parse or verdict program. If adding a sock object to a map would result - * in having multiple parsing programs the update will return an EBUSY error. - * - * For reference this program is similar to devmap used in XDP context - * reviewing these together may be useful. For an example please review - * ./samples/bpf/sockmap/. - */ -#include <linux/bpf.h> -#include <net/sock.h> -#include <linux/filter.h> -#include <linux/errno.h> -#include <linux/file.h> -#include <linux/kernel.h> -#include <linux/net.h> -#include <linux/skbuff.h> -#include <linux/workqueue.h> -#include <linux/list.h> -#include <linux/mm.h> -#include <net/strparser.h> -#include <net/tcp.h> -#include <linux/ptr_ring.h> -#include <net/inet_common.h> -#include <linux/sched/signal.h> - -#define SOCK_CREATE_FLAG_MASK \ - (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY) - -struct bpf_sock_progs { - struct bpf_prog *bpf_tx_msg; - struct bpf_prog *bpf_parse; - struct bpf_prog *bpf_verdict; -}; - -struct bpf_stab { - struct bpf_map map; - struct sock **sock_map; - struct bpf_sock_progs progs; - raw_spinlock_t lock; -}; - -struct bucket { - struct hlist_head head; - raw_spinlock_t lock; -}; - -struct bpf_htab { - struct bpf_map map; - struct bucket *buckets; - atomic_t count; - u32 n_buckets; - u32 elem_size; - struct bpf_sock_progs progs; - struct rcu_head rcu; -}; - -struct htab_elem { - struct rcu_head rcu; - struct hlist_node hash_node; - u32 hash; - struct sock *sk; - char key[0]; -}; - -enum smap_psock_state { - SMAP_TX_RUNNING, -}; - -struct smap_psock_map_entry { - struct list_head list; - struct bpf_map *map; - struct sock **entry; - struct htab_elem __rcu *hash_link; -}; - -struct smap_psock { - struct rcu_head rcu; - refcount_t refcnt; - - /* datapath variables */ - struct sk_buff_head rxqueue; - bool strp_enabled; - - /* datapath error path cache across tx work invocations */ - int save_rem; - int save_off; - struct sk_buff *save_skb; - - /* datapath variables for tx_msg ULP */ - struct sock *sk_redir; - int apply_bytes; - int cork_bytes; - int sg_size; - int eval; - struct sk_msg_buff *cork; - struct list_head ingress; - - struct strparser strp; - struct bpf_prog *bpf_tx_msg; - struct bpf_prog *bpf_parse; - struct bpf_prog *bpf_verdict; - struct list_head maps; - spinlock_t maps_lock; - - /* Back reference used when sock callback trigger sockmap operations */ - struct sock *sock; - unsigned long state; - - struct work_struct tx_work; - struct work_struct gc_work; - - struct proto *sk_proto; - void (*save_unhash)(struct sock *sk); - void (*save_close)(struct sock *sk, long timeout); - void (*save_data_ready)(struct sock *sk); - void (*save_write_space)(struct sock *sk); -}; - -static void smap_release_sock(struct smap_psock *psock, struct sock *sock); -static int bpf_tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, - int nonblock, int flags, int *addr_len); -static int bpf_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); -static int bpf_tcp_sendpage(struct sock *sk, struct page *page, - int offset, size_t size, int flags); -static void bpf_tcp_unhash(struct sock *sk); -static void bpf_tcp_close(struct sock *sk, long timeout); - -static inline struct smap_psock *smap_psock_sk(const struct sock *sk) -{ - return rcu_dereference_sk_user_data(sk); -} - -static bool bpf_tcp_stream_read(const struct sock *sk) -{ - struct smap_psock *psock; - bool empty = true; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) - goto out; - empty = list_empty(&psock->ingress); -out: - rcu_read_unlock(); - return !empty; -} - -enum { - SOCKMAP_IPV4, - SOCKMAP_IPV6, - SOCKMAP_NUM_PROTS, -}; - -enum { - SOCKMAP_BASE, - SOCKMAP_TX, - SOCKMAP_NUM_CONFIGS, -}; - -static struct proto *saved_tcpv6_prot __read_mostly; -static DEFINE_SPINLOCK(tcpv6_prot_lock); -static struct proto bpf_tcp_prots[SOCKMAP_NUM_PROTS][SOCKMAP_NUM_CONFIGS]; -static void build_protos(struct proto prot[SOCKMAP_NUM_CONFIGS], - struct proto *base) -{ - prot[SOCKMAP_BASE] = *base; - prot[SOCKMAP_BASE].unhash = bpf_tcp_unhash; - prot[SOCKMAP_BASE].close = bpf_tcp_close; - prot[SOCKMAP_BASE].recvmsg = bpf_tcp_recvmsg; - prot[SOCKMAP_BASE].stream_memory_read = bpf_tcp_stream_read; - - prot[SOCKMAP_TX] = prot[SOCKMAP_BASE]; - prot[SOCKMAP_TX].sendmsg = bpf_tcp_sendmsg; - prot[SOCKMAP_TX].sendpage = bpf_tcp_sendpage; -} - -static void update_sk_prot(struct sock *sk, struct smap_psock *psock) -{ - int family = sk->sk_family == AF_INET6 ? SOCKMAP_IPV6 : SOCKMAP_IPV4; - int conf = psock->bpf_tx_msg ? SOCKMAP_TX : SOCKMAP_BASE; - - sk->sk_prot = &bpf_tcp_prots[family][conf]; -} - -static int bpf_tcp_init(struct sock *sk) -{ - struct smap_psock *psock; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) { - rcu_read_unlock(); - return -EINVAL; - } - - if (unlikely(psock->sk_proto)) { - rcu_read_unlock(); - return -EBUSY; - } - - psock->save_unhash = sk->sk_prot->unhash; - psock->save_close = sk->sk_prot->close; - psock->sk_proto = sk->sk_prot; - - /* Build IPv6 sockmap whenever the address of tcpv6_prot changes */ - if (sk->sk_family == AF_INET6 && - unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) { - spin_lock_bh(&tcpv6_prot_lock); - if (likely(sk->sk_prot != saved_tcpv6_prot)) { - build_protos(bpf_tcp_prots[SOCKMAP_IPV6], sk->sk_prot); - smp_store_release(&saved_tcpv6_prot, sk->sk_prot); - } - spin_unlock_bh(&tcpv6_prot_lock); - } - update_sk_prot(sk, psock); - rcu_read_unlock(); - return 0; -} - -static void smap_release_sock(struct smap_psock *psock, struct sock *sock); -static int free_start_sg(struct sock *sk, struct sk_msg_buff *md, bool charge); - -static void bpf_tcp_release(struct sock *sk) -{ - struct smap_psock *psock; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) - goto out; - - if (psock->cork) { - free_start_sg(psock->sock, psock->cork, true); - kfree(psock->cork); - psock->cork = NULL; - } - - if (psock->sk_proto) { - sk->sk_prot = psock->sk_proto; - psock->sk_proto = NULL; - } -out: - rcu_read_unlock(); -} - -static struct htab_elem *lookup_elem_raw(struct hlist_head *head, - u32 hash, void *key, u32 key_size) -{ - struct htab_elem *l; - - hlist_for_each_entry_rcu(l, head, hash_node) { - if (l->hash == hash && !memcmp(&l->key, key, key_size)) - return l; - } - - return NULL; -} - -static inline struct bucket *__select_bucket(struct bpf_htab *htab, u32 hash) -{ - return &htab->buckets[hash & (htab->n_buckets - 1)]; -} - -static inline struct hlist_head *select_bucket(struct bpf_htab *htab, u32 hash) -{ - return &__select_bucket(htab, hash)->head; -} - -static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l) -{ - atomic_dec(&htab->count); - kfree_rcu(l, rcu); -} - -static struct smap_psock_map_entry *psock_map_pop(struct sock *sk, - struct smap_psock *psock) -{ - struct smap_psock_map_entry *e; - - spin_lock_bh(&psock->maps_lock); - e = list_first_entry_or_null(&psock->maps, - struct smap_psock_map_entry, - list); - if (e) - list_del(&e->list); - spin_unlock_bh(&psock->maps_lock); - return e; -} - -static void bpf_tcp_remove(struct sock *sk, struct smap_psock *psock) -{ - struct smap_psock_map_entry *e; - struct sk_msg_buff *md, *mtmp; - struct sock *osk; - - if (psock->cork) { - free_start_sg(psock->sock, psock->cork, true); - kfree(psock->cork); - psock->cork = NULL; - } - - list_for_each_entry_safe(md, mtmp, &psock->ingress, list) { - list_del(&md->list); - free_start_sg(psock->sock, md, true); - kfree(md); - } - - e = psock_map_pop(sk, psock); - while (e) { - if (e->entry) { - struct bpf_stab *stab = container_of(e->map, struct bpf_stab, map); - - raw_spin_lock_bh(&stab->lock); - osk = *e->entry; - if (osk == sk) { - *e->entry = NULL; - smap_release_sock(psock, sk); - } - raw_spin_unlock_bh(&stab->lock); - } else { - struct htab_elem *link = rcu_dereference(e->hash_link); - struct bpf_htab *htab = container_of(e->map, struct bpf_htab, map); - struct hlist_head *head; - struct htab_elem *l; - struct bucket *b; - - b = __select_bucket(htab, link->hash); - head = &b->head; - raw_spin_lock_bh(&b->lock); - l = lookup_elem_raw(head, - link->hash, link->key, - htab->map.key_size); - /* If another thread deleted this object skip deletion. - * The refcnt on psock may or may not be zero. - */ - if (l && l == link) { - hlist_del_rcu(&link->hash_node); - smap_release_sock(psock, link->sk); - free_htab_elem(htab, link); - } - raw_spin_unlock_bh(&b->lock); - } - kfree(e); - e = psock_map_pop(sk, psock); - } -} - -static void bpf_tcp_unhash(struct sock *sk) -{ - void (*unhash_fun)(struct sock *sk); - struct smap_psock *psock; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) { - rcu_read_unlock(); - if (sk->sk_prot->unhash) - sk->sk_prot->unhash(sk); - return; - } - unhash_fun = psock->save_unhash; - bpf_tcp_remove(sk, psock); - rcu_read_unlock(); - unhash_fun(sk); -} - -static void bpf_tcp_close(struct sock *sk, long timeout) -{ - void (*close_fun)(struct sock *sk, long timeout); - struct smap_psock *psock; - - lock_sock(sk); - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) { - rcu_read_unlock(); - release_sock(sk); - return sk->sk_prot->close(sk, timeout); - } - close_fun = psock->save_close; - bpf_tcp_remove(sk, psock); - rcu_read_unlock(); - release_sock(sk); - close_fun(sk, timeout); -} - -enum __sk_action { - __SK_DROP = 0, - __SK_PASS, - __SK_REDIRECT, - __SK_NONE, -}; - -static struct tcp_ulp_ops bpf_tcp_ulp_ops __read_mostly = { - .name = "bpf_tcp", - .uid = TCP_ULP_BPF, - .user_visible = false, - .owner = NULL, - .init = bpf_tcp_init, - .release = bpf_tcp_release, -}; - -static int memcopy_from_iter(struct sock *sk, - struct sk_msg_buff *md, - struct iov_iter *from, int bytes) -{ - struct scatterlist *sg = md->sg_data; - int i = md->sg_curr, rc = -ENOSPC; - - do { - int copy; - char *to; - - if (md->sg_copybreak >= sg[i].length) { - md->sg_copybreak = 0; - - if (++i == MAX_SKB_FRAGS) - i = 0; - - if (i == md->sg_end) - break; - } - - copy = sg[i].length - md->sg_copybreak; - to = sg_virt(&sg[i]) + md->sg_copybreak; - md->sg_copybreak += copy; - - if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) - rc = copy_from_iter_nocache(to, copy, from); - else - rc = copy_from_iter(to, copy, from); - - if (rc != copy) { - rc = -EFAULT; - goto out; - } - - bytes -= copy; - if (!bytes) - break; - - md->sg_copybreak = 0; - if (++i == MAX_SKB_FRAGS) - i = 0; - } while (i != md->sg_end); -out: - md->sg_curr = i; - return rc; -} - -static int bpf_tcp_push(struct sock *sk, int apply_bytes, - struct sk_msg_buff *md, - int flags, bool uncharge) -{ - bool apply = apply_bytes; - struct scatterlist *sg; - int offset, ret = 0; - struct page *p; - size_t size; - - while (1) { - sg = md->sg_data + md->sg_start; - size = (apply && apply_bytes < sg->length) ? - apply_bytes : sg->length; - offset = sg->offset; - - tcp_rate_check_app_limited(sk); - p = sg_page(sg); -retry: - ret = do_tcp_sendpages(sk, p, offset, size, flags); - if (ret != size) { - if (ret > 0) { - if (apply) - apply_bytes -= ret; - - sg->offset += ret; - sg->length -= ret; - size -= ret; - offset += ret; - if (uncharge) - sk_mem_uncharge(sk, ret); - goto retry; - } - - return ret; - } - - if (apply) - apply_bytes -= ret; - sg->offset += ret; - sg->length -= ret; - if (uncharge) - sk_mem_uncharge(sk, ret); - - if (!sg->length) { - put_page(p); - md->sg_start++; - if (md->sg_start == MAX_SKB_FRAGS) - md->sg_start = 0; - sg_init_table(sg, 1); - - if (md->sg_start == md->sg_end) - break; - } - - if (apply && !apply_bytes) - break; - } - return 0; -} - -static inline void bpf_compute_data_pointers_sg(struct sk_msg_buff *md) -{ - struct scatterlist *sg = md->sg_data + md->sg_start; - - if (md->sg_copy[md->sg_start]) { - md->data = md->data_end = 0; - } else { - md->data = sg_virt(sg); - md->data_end = md->data + sg->length; - } -} - -static void return_mem_sg(struct sock *sk, int bytes, struct sk_msg_buff *md) -{ - struct scatterlist *sg = md->sg_data; - int i = md->sg_start; - - do { - int uncharge = (bytes < sg[i].length) ? bytes : sg[i].length; - - sk_mem_uncharge(sk, uncharge); - bytes -= uncharge; - if (!bytes) - break; - i++; - if (i == MAX_SKB_FRAGS) - i = 0; - } while (i != md->sg_end); -} - -static void free_bytes_sg(struct sock *sk, int bytes, - struct sk_msg_buff *md, bool charge) -{ - struct scatterlist *sg = md->sg_data; - int i = md->sg_start, free; - - while (bytes && sg[i].length) { - free = sg[i].length; - if (bytes < free) { - sg[i].length -= bytes; - sg[i].offset += bytes; - if (charge) - sk_mem_uncharge(sk, bytes); - break; - } - - if (charge) - sk_mem_uncharge(sk, sg[i].length); - put_page(sg_page(&sg[i])); - bytes -= sg[i].length; - sg[i].length = 0; - sg[i].page_link = 0; - sg[i].offset = 0; - i++; - - if (i == MAX_SKB_FRAGS) - i = 0; - } - md->sg_start = i; -} - -static int free_sg(struct sock *sk, int start, - struct sk_msg_buff *md, bool charge) -{ - struct scatterlist *sg = md->sg_data; - int i = start, free = 0; - - while (sg[i].length) { - free += sg[i].length; - if (charge) - sk_mem_uncharge(sk, sg[i].length); - if (!md->skb) - put_page(sg_page(&sg[i])); - sg[i].length = 0; - sg[i].page_link = 0; - sg[i].offset = 0; - i++; - - if (i == MAX_SKB_FRAGS) - i = 0; - } - if (md->skb) - consume_skb(md->skb); - - return free; -} - -static int free_start_sg(struct sock *sk, struct sk_msg_buff *md, bool charge) -{ - int free = free_sg(sk, md->sg_start, md, charge); - - md->sg_start = md->sg_end; - return free; -} - -static int free_curr_sg(struct sock *sk, struct sk_msg_buff *md) -{ - return free_sg(sk, md->sg_curr, md, true); -} - -static int bpf_map_msg_verdict(int _rc, struct sk_msg_buff *md) -{ - return ((_rc == SK_PASS) ? - (md->sk_redir ? __SK_REDIRECT : __SK_PASS) : - __SK_DROP); -} - -static unsigned int smap_do_tx_msg(struct sock *sk, - struct smap_psock *psock, - struct sk_msg_buff *md) -{ - struct bpf_prog *prog; - unsigned int rc, _rc; - - preempt_disable(); - rcu_read_lock(); - - /* If the policy was removed mid-send then default to 'accept' */ - prog = READ_ONCE(psock->bpf_tx_msg); - if (unlikely(!prog)) { - _rc = SK_PASS; - goto verdict; - } - - bpf_compute_data_pointers_sg(md); - md->sk = sk; - rc = (*prog->bpf_func)(md, prog->insnsi); - psock->apply_bytes = md->apply_bytes; - - /* Moving return codes from UAPI namespace into internal namespace */ - _rc = bpf_map_msg_verdict(rc, md); - - /* The psock has a refcount on the sock but not on the map and because - * we need to drop rcu read lock here its possible the map could be - * removed between here and when we need it to execute the sock - * redirect. So do the map lookup now for future use. - */ - if (_rc == __SK_REDIRECT) { - if (psock->sk_redir) - sock_put(psock->sk_redir); - psock->sk_redir = do_msg_redirect_map(md); - if (!psock->sk_redir) { - _rc = __SK_DROP; - goto verdict; - } - sock_hold(psock->sk_redir); - } -verdict: - rcu_read_unlock(); - preempt_enable(); - - return _rc; -} - -static int bpf_tcp_ingress(struct sock *sk, int apply_bytes, - struct smap_psock *psock, - struct sk_msg_buff *md, int flags) -{ - bool apply = apply_bytes; - size_t size, copied = 0; - struct sk_msg_buff *r; - int err = 0, i; - - r = kzalloc(sizeof(struct sk_msg_buff), __GFP_NOWARN | GFP_KERNEL); - if (unlikely(!r)) - return -ENOMEM; - - lock_sock(sk); - r->sg_start = md->sg_start; - i = md->sg_start; - - do { - size = (apply && apply_bytes < md->sg_data[i].length) ? - apply_bytes : md->sg_data[i].length; - - if (!sk_wmem_schedule(sk, size)) { - if (!copied) - err = -ENOMEM; - break; - } - - sk_mem_charge(sk, size); - r->sg_data[i] = md->sg_data[i]; - r->sg_data[i].length = size; - md->sg_data[i].length -= size; - md->sg_data[i].offset += size; - copied += size; - - if (md->sg_data[i].length) { - get_page(sg_page(&r->sg_data[i])); - r->sg_end = (i + 1) == MAX_SKB_FRAGS ? 0 : i + 1; - } else { - i++; - if (i == MAX_SKB_FRAGS) - i = 0; - r->sg_end = i; - } - - if (apply) { - apply_bytes -= size; - if (!apply_bytes) - break; - } - } while (i != md->sg_end); - - md->sg_start = i; - - if (!err) { - list_add_tail(&r->list, &psock->ingress); - sk->sk_data_ready(sk); - } else { - free_start_sg(sk, r, true); - kfree(r); - } - - release_sock(sk); - return err; -} - -static int bpf_tcp_sendmsg_do_redirect(struct sock *sk, int send, - struct sk_msg_buff *md, - int flags) -{ - bool ingress = !!(md->flags & BPF_F_INGRESS); - struct smap_psock *psock; - int err = 0; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) - goto out_rcu; - - if (!refcount_inc_not_zero(&psock->refcnt)) - goto out_rcu; - - rcu_read_unlock(); - - if (ingress) { - err = bpf_tcp_ingress(sk, send, psock, md, flags); - } else { - lock_sock(sk); - err = bpf_tcp_push(sk, send, md, flags, false); - release_sock(sk); - } - smap_release_sock(psock, sk); - return err; -out_rcu: - rcu_read_unlock(); - return 0; -} - -static inline void bpf_md_init(struct smap_psock *psock) -{ - if (!psock->apply_bytes) { - psock->eval = __SK_NONE; - if (psock->sk_redir) { - sock_put(psock->sk_redir); - psock->sk_redir = NULL; - } - } -} - -static void apply_bytes_dec(struct smap_psock *psock, int i) -{ - if (psock->apply_bytes) { - if (psock->apply_bytes < i) - psock->apply_bytes = 0; - else - psock->apply_bytes -= i; - } -} - -static int bpf_exec_tx_verdict(struct smap_psock *psock, - struct sk_msg_buff *m, - struct sock *sk, - int *copied, int flags) -{ - bool cork = false, enospc = (m->sg_start == m->sg_end); - struct sock *redir; - int err = 0; - int send; - -more_data: - if (psock->eval == __SK_NONE) - psock->eval = smap_do_tx_msg(sk, psock, m); - - if (m->cork_bytes && - m->cork_bytes > psock->sg_size && !enospc) { - psock->cork_bytes = m->cork_bytes - psock->sg_size; - if (!psock->cork) { - psock->cork = kcalloc(1, - sizeof(struct sk_msg_buff), - GFP_ATOMIC | __GFP_NOWARN); - - if (!psock->cork) { - err = -ENOMEM; - goto out_err; - } - } - memcpy(psock->cork, m, sizeof(*m)); - goto out_err; - } - - send = psock->sg_size; - if (psock->apply_bytes && psock->apply_bytes < send) - send = psock->apply_bytes; - - switch (psock->eval) { - case __SK_PASS: - err = bpf_tcp_push(sk, send, m, flags, true); - if (unlikely(err)) { - *copied -= free_start_sg(sk, m, true); - break; - } - - apply_bytes_dec(psock, send); - psock->sg_size -= send; - break; - case __SK_REDIRECT: - redir = psock->sk_redir; - apply_bytes_dec(psock, send); - - if (psock->cork) { - cork = true; - psock->cork = NULL; - } - - return_mem_sg(sk, send, m); - release_sock(sk); - - err = bpf_tcp_sendmsg_do_redirect(redir, send, m, flags); - lock_sock(sk); - - if (unlikely(err < 0)) { - int free = free_start_sg(sk, m, false); - - psock->sg_size = 0; - if (!cork) - *copied -= free; - } else { - psock->sg_size -= send; - } - - if (cork) { - free_start_sg(sk, m, true); - psock->sg_size = 0; - kfree(m); - m = NULL; - err = 0; - } - break; - case __SK_DROP: - default: - free_bytes_sg(sk, send, m, true); - apply_bytes_dec(psock, send); - *copied -= send; - psock->sg_size -= send; - err = -EACCES; - break; - } - - if (likely(!err)) { - bpf_md_init(psock); - if (m && - m->sg_data[m->sg_start].page_link && - m->sg_data[m->sg_start].length) - goto more_data; - } - -out_err: - return err; -} - -static int bpf_wait_data(struct sock *sk, - struct smap_psock *psk, int flags, - long timeo, int *err) -{ - int rc; - - DEFINE_WAIT_FUNC(wait, woken_wake_function); - - add_wait_queue(sk_sleep(sk), &wait); - sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); - rc = sk_wait_event(sk, &timeo, - !list_empty(&psk->ingress) || - !skb_queue_empty(&sk->sk_receive_queue), - &wait); - sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); - remove_wait_queue(sk_sleep(sk), &wait); - - return rc; -} - -static int bpf_tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, - int nonblock, int flags, int *addr_len) -{ - struct iov_iter *iter = &msg->msg_iter; - struct smap_psock *psock; - int copied = 0; - - if (unlikely(flags & MSG_ERRQUEUE)) - return inet_recv_error(sk, msg, len, addr_len); - if (!skb_queue_empty(&sk->sk_receive_queue)) - return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) - goto out; - - if (unlikely(!refcount_inc_not_zero(&psock->refcnt))) - goto out; - rcu_read_unlock(); - - lock_sock(sk); -bytes_ready: - while (copied != len) { - struct scatterlist *sg; - struct sk_msg_buff *md; - int i; - - md = list_first_entry_or_null(&psock->ingress, - struct sk_msg_buff, list); - if (unlikely(!md)) - break; - i = md->sg_start; - do { - struct page *page; - int n, copy; - - sg = &md->sg_data[i]; - copy = sg->length; - page = sg_page(sg); - - if (copied + copy > len) - copy = len - copied; - - n = copy_page_to_iter(page, sg->offset, copy, iter); - if (n != copy) { - md->sg_start = i; - release_sock(sk); - smap_release_sock(psock, sk); - return -EFAULT; - } - - copied += copy; - sg->offset += copy; - sg->length -= copy; - sk_mem_uncharge(sk, copy); - - if (!sg->length) { - i++; - if (i == MAX_SKB_FRAGS) - i = 0; - if (!md->skb) - put_page(page); - } - if (copied == len) - break; - } while (i != md->sg_end); - md->sg_start = i; - - if (!sg->length && md->sg_start == md->sg_end) { - list_del(&md->list); - if (md->skb) - consume_skb(md->skb); - kfree(md); - } - } - - if (!copied) { - long timeo; - int data; - int err = 0; - - timeo = sock_rcvtimeo(sk, nonblock); - data = bpf_wait_data(sk, psock, flags, timeo, &err); - - if (data) { - if (!skb_queue_empty(&sk->sk_receive_queue)) { - release_sock(sk); - smap_release_sock(psock, sk); - copied = tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); - return copied; - } - goto bytes_ready; - } - - if (err) - copied = err; - } - - release_sock(sk); - smap_release_sock(psock, sk); - return copied; -out: - rcu_read_unlock(); - return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); -} - - -static int bpf_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) -{ - int flags = msg->msg_flags | MSG_NO_SHARED_FRAGS; - struct sk_msg_buff md = {0}; - unsigned int sg_copy = 0; - struct smap_psock *psock; - int copied = 0, err = 0; - struct scatterlist *sg; - long timeo; - - /* Its possible a sock event or user removed the psock _but_ the ops - * have not been reprogrammed yet so we get here. In this case fallback - * to tcp_sendmsg. Note this only works because we _only_ ever allow - * a single ULP there is no hierarchy here. - */ - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) { - rcu_read_unlock(); - return tcp_sendmsg(sk, msg, size); - } - - /* Increment the psock refcnt to ensure its not released while sending a - * message. Required because sk lookup and bpf programs are used in - * separate rcu critical sections. Its OK if we lose the map entry - * but we can't lose the sock reference. - */ - if (!refcount_inc_not_zero(&psock->refcnt)) { - rcu_read_unlock(); - return tcp_sendmsg(sk, msg, size); - } - - sg = md.sg_data; - sg_init_marker(sg, MAX_SKB_FRAGS); - rcu_read_unlock(); - - lock_sock(sk); - timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); - - while (msg_data_left(msg)) { - struct sk_msg_buff *m = NULL; - bool enospc = false; - int copy; - - if (sk->sk_err) { - err = -sk->sk_err; - goto out_err; - } - - copy = msg_data_left(msg); - if (!sk_stream_memory_free(sk)) - goto wait_for_sndbuf; - - m = psock->cork_bytes ? psock->cork : &md; - m->sg_curr = m->sg_copybreak ? m->sg_curr : m->sg_end; - err = sk_alloc_sg(sk, copy, m->sg_data, - m->sg_start, &m->sg_end, &sg_copy, - m->sg_end - 1); - if (err) { - if (err != -ENOSPC) - goto wait_for_memory; - enospc = true; - copy = sg_copy; - } - - err = memcopy_from_iter(sk, m, &msg->msg_iter, copy); - if (err < 0) { - free_curr_sg(sk, m); - goto out_err; - } - - psock->sg_size += copy; - copied += copy; - sg_copy = 0; - - /* When bytes are being corked skip running BPF program and - * applying verdict unless there is no more buffer space. In - * the ENOSPC case simply run BPF prorgram with currently - * accumulated data. We don't have much choice at this point - * we could try extending the page frags or chaining complex - * frags but even in these cases _eventually_ we will hit an - * OOM scenario. More complex recovery schemes may be - * implemented in the future, but BPF programs must handle - * the case where apply_cork requests are not honored. The - * canonical method to verify this is to check data length. - */ - if (psock->cork_bytes) { - if (copy > psock->cork_bytes) - psock->cork_bytes = 0; - else - psock->cork_bytes -= copy; - - if (psock->cork_bytes && !enospc) - goto out_cork; - - /* All cork bytes accounted for re-run filter */ - psock->eval = __SK_NONE; - psock->cork_bytes = 0; - } - - err = bpf_exec_tx_verdict(psock, m, sk, &copied, flags); - if (unlikely(err < 0)) - goto out_err; - continue; -wait_for_sndbuf: - set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); -wait_for_memory: - err = sk_stream_wait_memory(sk, &timeo); - if (err) { - if (m && m != psock->cork) - free_start_sg(sk, m, true); - goto out_err; - } - } -out_err: - if (err < 0) - err = sk_stream_error(sk, msg->msg_flags, err); -out_cork: - release_sock(sk); - smap_release_sock(psock, sk); - return copied ? copied : err; -} - -static int bpf_tcp_sendpage(struct sock *sk, struct page *page, - int offset, size_t size, int flags) -{ - struct sk_msg_buff md = {0}, *m = NULL; - int err = 0, copied = 0; - struct smap_psock *psock; - struct scatterlist *sg; - bool enospc = false; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (unlikely(!psock)) - goto accept; - - if (!refcount_inc_not_zero(&psock->refcnt)) - goto accept; - rcu_read_unlock(); - - lock_sock(sk); - - if (psock->cork_bytes) { - m = psock->cork; - sg = &m->sg_data[m->sg_end]; - } else { - m = &md; - sg = m->sg_data; - sg_init_marker(sg, MAX_SKB_FRAGS); - } - - /* Catch case where ring is full and sendpage is stalled. */ - if (unlikely(m->sg_end == m->sg_start && - m->sg_data[m->sg_end].length)) - goto out_err; - - psock->sg_size += size; - sg_set_page(sg, page, size, offset); - get_page(page); - m->sg_copy[m->sg_end] = true; - sk_mem_charge(sk, size); - m->sg_end++; - copied = size; - - if (m->sg_end == MAX_SKB_FRAGS) - m->sg_end = 0; - - if (m->sg_end == m->sg_start) - enospc = true; - - if (psock->cork_bytes) { - if (size > psock->cork_bytes) - psock->cork_bytes = 0; - else - psock->cork_bytes -= size; - - if (psock->cork_bytes && !enospc) - goto out_err; - - /* All cork bytes accounted for re-run filter */ - psock->eval = __SK_NONE; - psock->cork_bytes = 0; - } - - err = bpf_exec_tx_verdict(psock, m, sk, &copied, flags); -out_err: - release_sock(sk); - smap_release_sock(psock, sk); - return copied ? copied : err; -accept: - rcu_read_unlock(); - return tcp_sendpage(sk, page, offset, size, flags); -} - -static void bpf_tcp_msg_add(struct smap_psock *psock, - struct sock *sk, - struct bpf_prog *tx_msg) -{ - struct bpf_prog *orig_tx_msg; - - orig_tx_msg = xchg(&psock->bpf_tx_msg, tx_msg); - if (orig_tx_msg) - bpf_prog_put(orig_tx_msg); -} - -static int bpf_tcp_ulp_register(void) -{ - build_protos(bpf_tcp_prots[SOCKMAP_IPV4], &tcp_prot); - /* Once BPF TX ULP is registered it is never unregistered. It - * will be in the ULP list for the lifetime of the system. Doing - * duplicate registers is not a problem. - */ - return tcp_register_ulp(&bpf_tcp_ulp_ops); -} - -static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb) -{ - struct bpf_prog *prog = READ_ONCE(psock->bpf_verdict); - int rc; - - if (unlikely(!prog)) - return __SK_DROP; - - skb_orphan(skb); - /* We need to ensure that BPF metadata for maps is also cleared - * when we orphan the skb so that we don't have the possibility - * to reference a stale map. - */ - TCP_SKB_CB(skb)->bpf.sk_redir = NULL; - skb->sk = psock->sock; - bpf_compute_data_end_sk_skb(skb); - preempt_disable(); - rc = (*prog->bpf_func)(skb, prog->insnsi); - preempt_enable(); - skb->sk = NULL; - - /* Moving return codes from UAPI namespace into internal namespace */ - return rc == SK_PASS ? - (TCP_SKB_CB(skb)->bpf.sk_redir ? __SK_REDIRECT : __SK_PASS) : - __SK_DROP; -} - -static int smap_do_ingress(struct smap_psock *psock, struct sk_buff *skb) -{ - struct sock *sk = psock->sock; - int copied = 0, num_sg; - struct sk_msg_buff *r; - - r = kzalloc(sizeof(struct sk_msg_buff), __GFP_NOWARN | GFP_ATOMIC); - if (unlikely(!r)) - return -EAGAIN; - - if (!sk_rmem_schedule(sk, skb, skb->len)) { - kfree(r); - return -EAGAIN; - } - - sg_init_table(r->sg_data, MAX_SKB_FRAGS); - num_sg = skb_to_sgvec(skb, r->sg_data, 0, skb->len); - if (unlikely(num_sg < 0)) { - kfree(r); - return num_sg; - } - sk_mem_charge(sk, skb->len); - copied = skb->len; - r->sg_start = 0; - r->sg_end = num_sg == MAX_SKB_FRAGS ? 0 : num_sg; - r->skb = skb; - list_add_tail(&r->list, &psock->ingress); - sk->sk_data_ready(sk); - return copied; -} - -static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb) -{ - struct smap_psock *peer; - struct sock *sk; - __u32 in; - int rc; - - rc = smap_verdict_func(psock, skb); - switch (rc) { - case __SK_REDIRECT: - sk = do_sk_redirect_map(skb); - if (!sk) { - kfree_skb(skb); - break; - } - - peer = smap_psock_sk(sk); - in = (TCP_SKB_CB(skb)->bpf.flags) & BPF_F_INGRESS; - - if (unlikely(!peer || sock_flag(sk, SOCK_DEAD) || - !test_bit(SMAP_TX_RUNNING, &peer->state))) { - kfree_skb(skb); - break; - } - - if (!in && sock_writeable(sk)) { - skb_set_owner_w(skb, sk); - skb_queue_tail(&peer->rxqueue, skb); - schedule_work(&peer->tx_work); - break; - } else if (in && - atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) { - skb_queue_tail(&peer->rxqueue, skb); - schedule_work(&peer->tx_work); - break; - } - /* Fall through and free skb otherwise */ - case __SK_DROP: - default: - kfree_skb(skb); - } -} - -static void smap_report_sk_error(struct smap_psock *psock, int err) -{ - struct sock *sk = psock->sock; - - sk->sk_err = err; - sk->sk_error_report(sk); -} - -static void smap_read_sock_strparser(struct strparser *strp, - struct sk_buff *skb) -{ - struct smap_psock *psock; - - rcu_read_lock(); - psock = container_of(strp, struct smap_psock, strp); - smap_do_verdict(psock, skb); - rcu_read_unlock(); -} - -/* Called with lock held on socket */ -static void smap_data_ready(struct sock *sk) -{ - struct smap_psock *psock; - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (likely(psock)) { - write_lock_bh(&sk->sk_callback_lock); - strp_data_ready(&psock->strp); - write_unlock_bh(&sk->sk_callback_lock); - } - rcu_read_unlock(); -} - -static void smap_tx_work(struct work_struct *w) -{ - struct smap_psock *psock; - struct sk_buff *skb; - int rem, off, n; - - psock = container_of(w, struct smap_psock, tx_work); - - /* lock sock to avoid losing sk_socket at some point during loop */ - lock_sock(psock->sock); - if (psock->save_skb) { - skb = psock->save_skb; - rem = psock->save_rem; - off = psock->save_off; - psock->save_skb = NULL; - goto start; - } - - while ((skb = skb_dequeue(&psock->rxqueue))) { - __u32 flags; - - rem = skb->len; - off = 0; -start: - flags = (TCP_SKB_CB(skb)->bpf.flags) & BPF_F_INGRESS; - do { - if (likely(psock->sock->sk_socket)) { - if (flags) - n = smap_do_ingress(psock, skb); - else - n = skb_send_sock_locked(psock->sock, - skb, off, rem); - } else { - n = -EINVAL; - } - - if (n <= 0) { - if (n == -EAGAIN) { - /* Retry when space is available */ - psock->save_skb = skb; - psock->save_rem = rem; - psock->save_off = off; - goto out; - } - /* Hard errors break pipe and stop xmit */ - smap_report_sk_error(psock, n ? -n : EPIPE); - clear_bit(SMAP_TX_RUNNING, &psock->state); - kfree_skb(skb); - goto out; - } - rem -= n; - off += n; - } while (rem); - - if (!flags) - kfree_skb(skb); - } -out: - release_sock(psock->sock); -} - -static void smap_write_space(struct sock *sk) -{ - struct smap_psock *psock; - void (*write_space)(struct sock *sk); - - rcu_read_lock(); - psock = smap_psock_sk(sk); - if (likely(psock && test_bit(SMAP_TX_RUNNING, &psock->state))) - schedule_work(&psock->tx_work); - write_space = psock->save_write_space; - rcu_read_unlock(); - write_space(sk); -} - -static void smap_stop_sock(struct smap_psock *psock, struct sock *sk) -{ - if (!psock->strp_enabled) - return; - sk->sk_data_ready = psock->save_data_ready; - sk->sk_write_space = psock->save_write_space; - psock->save_data_ready = NULL; - psock->save_write_space = NULL; - strp_stop(&psock->strp); - psock->strp_enabled = false; -} - -static void smap_destroy_psock(struct rcu_head *rcu) -{ - struct smap_psock *psock = container_of(rcu, - struct smap_psock, rcu); - - /* Now that a grace period has passed there is no longer - * any reference to this sock in the sockmap so we can - * destroy the psock, strparser, and bpf programs. But, - * because we use workqueue sync operations we can not - * do it in rcu context - */ - schedule_work(&psock->gc_work); -} - -static bool psock_is_smap_sk(struct sock *sk) -{ - return inet_csk(sk)->icsk_ulp_ops == &bpf_tcp_ulp_ops; -} - -static void smap_release_sock(struct smap_psock *psock, struct sock *sock) -{ - if (refcount_dec_and_test(&psock->refcnt)) { - if (psock_is_smap_sk(sock)) - tcp_cleanup_ulp(sock); - write_lock_bh(&sock->sk_callback_lock); - smap_stop_sock(psock, sock); - write_unlock_bh(&sock->sk_callback_lock); - clear_bit(SMAP_TX_RUNNING, &psock->state); - rcu_assign_sk_user_data(sock, NULL); - call_rcu_sched(&psock->rcu, smap_destroy_psock); - } -} - -static int smap_parse_func_strparser(struct strparser *strp, - struct sk_buff *skb) -{ - struct smap_psock *psock; - struct bpf_prog *prog; - int rc; - - rcu_read_lock(); - psock = container_of(strp, struct smap_psock, strp); - prog = READ_ONCE(psock->bpf_parse); - - if (unlikely(!prog)) { - rcu_read_unlock(); - return skb->len; - } - - /* Attach socket for bpf program to use if needed we can do this - * because strparser clones the skb before handing it to a upper - * layer, meaning skb_orphan has been called. We NULL sk on the - * way out to ensure we don't trigger a BUG_ON in skb/sk operations - * later and because we are not charging the memory of this skb to - * any socket yet. - */ - skb->sk = psock->sock; - bpf_compute_data_end_sk_skb(skb); - rc = (*prog->bpf_func)(skb, prog->insnsi); - skb->sk = NULL; - rcu_read_unlock(); - return rc; -} - -static int smap_read_sock_done(struct strparser *strp, int err) -{ - return err; -} - -static int smap_init_sock(struct smap_psock *psock, - struct sock *sk) -{ - static const struct strp_callbacks cb = { - .rcv_msg = smap_read_sock_strparser, - .parse_msg = smap_parse_func_strparser, - .read_sock_done = smap_read_sock_done, - }; - - return strp_init(&psock->strp, sk, &cb); -} - -static void smap_init_progs(struct smap_psock *psock, - struct bpf_prog *verdict, - struct bpf_prog *parse) -{ - struct bpf_prog *orig_parse, *orig_verdict; - - orig_parse = xchg(&psock->bpf_parse, parse); - orig_verdict = xchg(&psock->bpf_verdict, verdict); - - if (orig_verdict) - bpf_prog_put(orig_verdict); - if (orig_parse) - bpf_prog_put(orig_parse); -} - -static void smap_start_sock(struct smap_psock *psock, struct sock *sk) -{ - if (sk->sk_data_ready == smap_data_ready) - return; - psock->save_data_ready = sk->sk_data_ready; - psock->save_write_space = sk->sk_write_space; - sk->sk_data_ready = smap_data_ready; - sk->sk_write_space = smap_write_space; - psock->strp_enabled = true; -} - -static void sock_map_remove_complete(struct bpf_stab *stab) -{ - bpf_map_area_free(stab->sock_map); - kfree(stab); -} - -static void smap_gc_work(struct work_struct *w) -{ - struct smap_psock_map_entry *e, *tmp; - struct sk_msg_buff *md, *mtmp; - struct smap_psock *psock; - - psock = container_of(w, struct smap_psock, gc_work); - - /* no callback lock needed because we already detached sockmap ops */ - if (psock->strp_enabled) - strp_done(&psock->strp); - - cancel_work_sync(&psock->tx_work); - __skb_queue_purge(&psock->rxqueue); - - /* At this point all strparser and xmit work must be complete */ - if (psock->bpf_parse) - bpf_prog_put(psock->bpf_parse); - if (psock->bpf_verdict) - bpf_prog_put(psock->bpf_verdict); - if (psock->bpf_tx_msg) - bpf_prog_put(psock->bpf_tx_msg); - - if (psock->cork) { - free_start_sg(psock->sock, psock->cork, true); - kfree(psock->cork); - } - - list_for_each_entry_safe(md, mtmp, &psock->ingress, list) { - list_del(&md->list); - free_start_sg(psock->sock, md, true); - kfree(md); - } - - list_for_each_entry_safe(e, tmp, &psock->maps, list) { - list_del(&e->list); - kfree(e); - } - - if (psock->sk_redir) - sock_put(psock->sk_redir); - - sock_put(psock->sock); - kfree(psock); -} - -static struct smap_psock *smap_init_psock(struct sock *sock, int node) -{ - struct smap_psock *psock; - - psock = kzalloc_node(sizeof(struct smap_psock), - GFP_ATOMIC | __GFP_NOWARN, - node); - if (!psock) - return ERR_PTR(-ENOMEM); - - psock->eval = __SK_NONE; - psock->sock = sock; - skb_queue_head_init(&psock->rxqueue); - INIT_WORK(&psock->tx_work, smap_tx_work); - INIT_WORK(&psock->gc_work, smap_gc_work); - INIT_LIST_HEAD(&psock->maps); - INIT_LIST_HEAD(&psock->ingress); - refcount_set(&psock->refcnt, 1); - spin_lock_init(&psock->maps_lock); - - rcu_assign_sk_user_data(sock, psock); - sock_hold(sock); - return psock; -} - -static struct bpf_map *sock_map_alloc(union bpf_attr *attr) -{ - struct bpf_stab *stab; - u64 cost; - int err; - - if (!capable(CAP_NET_ADMIN)) - return ERR_PTR(-EPERM); - - /* check sanity of attributes */ - if (attr->max_entries == 0 || attr->key_size != 4 || - attr->value_size != 4 || attr->map_flags & ~SOCK_CREATE_FLAG_MASK) - return ERR_PTR(-EINVAL); - - err = bpf_tcp_ulp_register(); - if (err && err != -EEXIST) - return ERR_PTR(err); - - stab = kzalloc(sizeof(*stab), GFP_USER); - if (!stab) - return ERR_PTR(-ENOMEM); - - bpf_map_init_from_attr(&stab->map, attr); - raw_spin_lock_init(&stab->lock); - - /* make sure page count doesn't overflow */ - cost = (u64) stab->map.max_entries * sizeof(struct sock *); - err = -EINVAL; - if (cost >= U32_MAX - PAGE_SIZE) - goto free_stab; - - stab->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT; - - /* if map size is larger than memlock limit, reject it early */ - err = bpf_map_precharge_memlock(stab->map.pages); - if (err) - goto free_stab; - - err = -ENOMEM; - stab->sock_map = bpf_map_area_alloc(stab->map.max_entries * - sizeof(struct sock *), - stab->map.numa_node); - if (!stab->sock_map) - goto free_stab; - - return &stab->map; -free_stab: - kfree(stab); - return ERR_PTR(err); -} - -static void smap_list_map_remove(struct smap_psock *psock, - struct sock **entry) -{ - struct smap_psock_map_entry *e, *tmp; - - spin_lock_bh(&psock->maps_lock); - list_for_each_entry_safe(e, tmp, &psock->maps, list) { - if (e->entry == entry) { - list_del(&e->list); - kfree(e); - } - } - spin_unlock_bh(&psock->maps_lock); -} - -static void smap_list_hash_remove(struct smap_psock *psock, - struct htab_elem *hash_link) -{ - struct smap_psock_map_entry *e, *tmp; - - spin_lock_bh(&psock->maps_lock); - list_for_each_entry_safe(e, tmp, &psock->maps, list) { - struct htab_elem *c = rcu_dereference(e->hash_link); - - if (c == hash_link) { - list_del(&e->list); - kfree(e); - } - } - spin_unlock_bh(&psock->maps_lock); -} - -static void sock_map_free(struct bpf_map *map) -{ - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - int i; - - synchronize_rcu(); - - /* At this point no update, lookup or delete operations can happen. - * However, be aware we can still get a socket state event updates, - * and data ready callabacks that reference the psock from sk_user_data - * Also psock worker threads are still in-flight. So smap_release_sock - * will only free the psock after cancel_sync on the worker threads - * and a grace period expire to ensure psock is really safe to remove. - */ - rcu_read_lock(); - raw_spin_lock_bh(&stab->lock); - for (i = 0; i < stab->map.max_entries; i++) { - struct smap_psock *psock; - struct sock *sock; - - sock = stab->sock_map[i]; - if (!sock) - continue; - stab->sock_map[i] = NULL; - psock = smap_psock_sk(sock); - /* This check handles a racing sock event that can get the - * sk_callback_lock before this case but after xchg happens - * causing the refcnt to hit zero and sock user data (psock) - * to be null and queued for garbage collection. - */ - if (likely(psock)) { - smap_list_map_remove(psock, &stab->sock_map[i]); - smap_release_sock(psock, sock); - } - } - raw_spin_unlock_bh(&stab->lock); - rcu_read_unlock(); - - sock_map_remove_complete(stab); -} - -static int sock_map_get_next_key(struct bpf_map *map, void *key, void *next_key) -{ - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - u32 i = key ? *(u32 *)key : U32_MAX; - u32 *next = (u32 *)next_key; - - if (i >= stab->map.max_entries) { - *next = 0; - return 0; - } - - if (i == stab->map.max_entries - 1) - return -ENOENT; - - *next = i + 1; - return 0; -} - -struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key) -{ - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - - if (key >= map->max_entries) - return NULL; - - return READ_ONCE(stab->sock_map[key]); -} - -static int sock_map_delete_elem(struct bpf_map *map, void *key) -{ - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - struct smap_psock *psock; - int k = *(u32 *)key; - struct sock *sock; - - if (k >= map->max_entries) - return -EINVAL; - - raw_spin_lock_bh(&stab->lock); - sock = stab->sock_map[k]; - stab->sock_map[k] = NULL; - raw_spin_unlock_bh(&stab->lock); - if (!sock) - return -EINVAL; - - psock = smap_psock_sk(sock); - if (!psock) - return 0; - if (psock->bpf_parse) { - write_lock_bh(&sock->sk_callback_lock); - smap_stop_sock(psock, sock); - write_unlock_bh(&sock->sk_callback_lock); - } - smap_list_map_remove(psock, &stab->sock_map[k]); - smap_release_sock(psock, sock); - return 0; -} - -/* Locking notes: Concurrent updates, deletes, and lookups are allowed and are - * done inside rcu critical sections. This ensures on updates that the psock - * will not be released via smap_release_sock() until concurrent updates/deletes - * complete. All operations operate on sock_map using cmpxchg and xchg - * operations to ensure we do not get stale references. Any reads into the - * map must be done with READ_ONCE() because of this. - * - * A psock is destroyed via call_rcu and after any worker threads are cancelled - * and syncd so we are certain all references from the update/lookup/delete - * operations as well as references in the data path are no longer in use. - * - * Psocks may exist in multiple maps, but only a single set of parse/verdict - * programs may be inherited from the maps it belongs to. A reference count - * is kept with the total number of references to the psock from all maps. The - * psock will not be released until this reaches zero. The psock and sock - * user data data use the sk_callback_lock to protect critical data structures - * from concurrent access. This allows us to avoid two updates from modifying - * the user data in sock and the lock is required anyways for modifying - * callbacks, we simply increase its scope slightly. - * - * Rules to follow, - * - psock must always be read inside RCU critical section - * - sk_user_data must only be modified inside sk_callback_lock and read - * inside RCU critical section. - * - psock->maps list must only be read & modified inside sk_callback_lock - * - sock_map must use READ_ONCE and (cmp)xchg operations - * - BPF verdict/parse programs must use READ_ONCE and xchg operations - */ - -static int __sock_map_ctx_update_elem(struct bpf_map *map, - struct bpf_sock_progs *progs, - struct sock *sock, - void *key) -{ - struct bpf_prog *verdict, *parse, *tx_msg; - struct smap_psock *psock; - bool new = false; - int err = 0; - - /* 1. If sock map has BPF programs those will be inherited by the - * sock being added. If the sock is already attached to BPF programs - * this results in an error. - */ - verdict = READ_ONCE(progs->bpf_verdict); - parse = READ_ONCE(progs->bpf_parse); - tx_msg = READ_ONCE(progs->bpf_tx_msg); - - if (parse && verdict) { - /* bpf prog refcnt may be zero if a concurrent attach operation - * removes the program after the above READ_ONCE() but before - * we increment the refcnt. If this is the case abort with an - * error. - */ - verdict = bpf_prog_inc_not_zero(verdict); - if (IS_ERR(verdict)) - return PTR_ERR(verdict); - - parse = bpf_prog_inc_not_zero(parse); - if (IS_ERR(parse)) { - bpf_prog_put(verdict); - return PTR_ERR(parse); - } - } - - if (tx_msg) { - tx_msg = bpf_prog_inc_not_zero(tx_msg); - if (IS_ERR(tx_msg)) { - if (parse && verdict) { - bpf_prog_put(parse); - bpf_prog_put(verdict); - } - return PTR_ERR(tx_msg); - } - } - - psock = smap_psock_sk(sock); - - /* 2. Do not allow inheriting programs if psock exists and has - * already inherited programs. This would create confusion on - * which parser/verdict program is running. If no psock exists - * create one. Inside sk_callback_lock to ensure concurrent create - * doesn't update user data. - */ - if (psock) { - if (!psock_is_smap_sk(sock)) { - err = -EBUSY; - goto out_progs; - } - if (READ_ONCE(psock->bpf_parse) && parse) { - err = -EBUSY; - goto out_progs; - } - if (READ_ONCE(psock->bpf_tx_msg) && tx_msg) { - err = -EBUSY; - goto out_progs; - } - if (!refcount_inc_not_zero(&psock->refcnt)) { - err = -EAGAIN; - goto out_progs; - } - } else { - psock = smap_init_psock(sock, map->numa_node); - if (IS_ERR(psock)) { - err = PTR_ERR(psock); - goto out_progs; - } - - set_bit(SMAP_TX_RUNNING, &psock->state); - new = true; - } - - /* 3. At this point we have a reference to a valid psock that is - * running. Attach any BPF programs needed. - */ - if (tx_msg) - bpf_tcp_msg_add(psock, sock, tx_msg); - if (new) { - err = tcp_set_ulp_id(sock, TCP_ULP_BPF); - if (err) - goto out_free; - } - - if (parse && verdict && !psock->strp_enabled) { - err = smap_init_sock(psock, sock); - if (err) - goto out_free; - smap_init_progs(psock, verdict, parse); - write_lock_bh(&sock->sk_callback_lock); - smap_start_sock(psock, sock); - write_unlock_bh(&sock->sk_callback_lock); - } - - return err; -out_free: - smap_release_sock(psock, sock); -out_progs: - if (parse && verdict) { - bpf_prog_put(parse); - bpf_prog_put(verdict); - } - if (tx_msg) - bpf_prog_put(tx_msg); - return err; -} - -static int sock_map_ctx_update_elem(struct bpf_sock_ops_kern *skops, - struct bpf_map *map, - void *key, u64 flags) -{ - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - struct bpf_sock_progs *progs = &stab->progs; - struct sock *osock, *sock = skops->sk; - struct smap_psock_map_entry *e; - struct smap_psock *psock; - u32 i = *(u32 *)key; - int err; - - if (unlikely(flags > BPF_EXIST)) - return -EINVAL; - if (unlikely(i >= stab->map.max_entries)) - return -E2BIG; - - e = kzalloc(sizeof(*e), GFP_ATOMIC | __GFP_NOWARN); - if (!e) - return -ENOMEM; - - err = __sock_map_ctx_update_elem(map, progs, sock, key); - if (err) - goto out; - - /* psock guaranteed to be present. */ - psock = smap_psock_sk(sock); - raw_spin_lock_bh(&stab->lock); - osock = stab->sock_map[i]; - if (osock && flags == BPF_NOEXIST) { - err = -EEXIST; - goto out_unlock; - } - if (!osock && flags == BPF_EXIST) { - err = -ENOENT; - goto out_unlock; - } - - e->entry = &stab->sock_map[i]; - e->map = map; - spin_lock_bh(&psock->maps_lock); - list_add_tail(&e->list, &psock->maps); - spin_unlock_bh(&psock->maps_lock); - - stab->sock_map[i] = sock; - if (osock) { - psock = smap_psock_sk(osock); - smap_list_map_remove(psock, &stab->sock_map[i]); - smap_release_sock(psock, osock); - } - raw_spin_unlock_bh(&stab->lock); - return 0; -out_unlock: - smap_release_sock(psock, sock); - raw_spin_unlock_bh(&stab->lock); -out: - kfree(e); - return err; -} - -int sock_map_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type) -{ - struct bpf_sock_progs *progs; - struct bpf_prog *orig; - - if (map->map_type == BPF_MAP_TYPE_SOCKMAP) { - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - - progs = &stab->progs; - } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH) { - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - - progs = &htab->progs; - } else { - return -EINVAL; - } - - switch (type) { - case BPF_SK_MSG_VERDICT: - orig = xchg(&progs->bpf_tx_msg, prog); - break; - case BPF_SK_SKB_STREAM_PARSER: - orig = xchg(&progs->bpf_parse, prog); - break; - case BPF_SK_SKB_STREAM_VERDICT: - orig = xchg(&progs->bpf_verdict, prog); - break; - default: - return -EOPNOTSUPP; - } - - if (orig) - bpf_prog_put(orig); - - return 0; -} - -int sockmap_get_from_fd(const union bpf_attr *attr, int type, - struct bpf_prog *prog) -{ - int ufd = attr->target_fd; - struct bpf_map *map; - struct fd f; - int err; - - f = fdget(ufd); - map = __bpf_map_get(f); - if (IS_ERR(map)) - return PTR_ERR(map); - - err = sock_map_prog(map, prog, attr->attach_type); - fdput(f); - return err; -} - -static void *sock_map_lookup(struct bpf_map *map, void *key) -{ - return NULL; -} - -static int sock_map_update_elem(struct bpf_map *map, - void *key, void *value, u64 flags) -{ - struct bpf_sock_ops_kern skops; - u32 fd = *(u32 *)value; - struct socket *socket; - int err; - - socket = sockfd_lookup(fd, &err); - if (!socket) - return err; - - skops.sk = socket->sk; - if (!skops.sk) { - fput(socket->file); - return -EINVAL; - } - - /* ULPs are currently supported only for TCP sockets in ESTABLISHED - * state. - */ - if (skops.sk->sk_type != SOCK_STREAM || - skops.sk->sk_protocol != IPPROTO_TCP || - skops.sk->sk_state != TCP_ESTABLISHED) { - fput(socket->file); - return -EOPNOTSUPP; - } - - lock_sock(skops.sk); - preempt_disable(); - rcu_read_lock(); - err = sock_map_ctx_update_elem(&skops, map, key, flags); - rcu_read_unlock(); - preempt_enable(); - release_sock(skops.sk); - fput(socket->file); - return err; -} - -static void sock_map_release(struct bpf_map *map) -{ - struct bpf_sock_progs *progs; - struct bpf_prog *orig; - - if (map->map_type == BPF_MAP_TYPE_SOCKMAP) { - struct bpf_stab *stab = container_of(map, struct bpf_stab, map); - - progs = &stab->progs; - } else { - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - - progs = &htab->progs; - } - - orig = xchg(&progs->bpf_parse, NULL); - if (orig) - bpf_prog_put(orig); - orig = xchg(&progs->bpf_verdict, NULL); - if (orig) - bpf_prog_put(orig); - - orig = xchg(&progs->bpf_tx_msg, NULL); - if (orig) - bpf_prog_put(orig); -} - -static struct bpf_map *sock_hash_alloc(union bpf_attr *attr) -{ - struct bpf_htab *htab; - int i, err; - u64 cost; - - if (!capable(CAP_NET_ADMIN)) - return ERR_PTR(-EPERM); - - /* check sanity of attributes */ - if (attr->max_entries == 0 || - attr->key_size == 0 || - attr->value_size != 4 || - attr->map_flags & ~SOCK_CREATE_FLAG_MASK) - return ERR_PTR(-EINVAL); - - if (attr->key_size > MAX_BPF_STACK) - /* eBPF programs initialize keys on stack, so they cannot be - * larger than max stack size - */ - return ERR_PTR(-E2BIG); - - err = bpf_tcp_ulp_register(); - if (err && err != -EEXIST) - return ERR_PTR(err); - - htab = kzalloc(sizeof(*htab), GFP_USER); - if (!htab) - return ERR_PTR(-ENOMEM); - - bpf_map_init_from_attr(&htab->map, attr); - - htab->n_buckets = roundup_pow_of_two(htab->map.max_entries); - htab->elem_size = sizeof(struct htab_elem) + - round_up(htab->map.key_size, 8); - err = -EINVAL; - if (htab->n_buckets == 0 || - htab->n_buckets > U32_MAX / sizeof(struct bucket)) - goto free_htab; - - cost = (u64) htab->n_buckets * sizeof(struct bucket) + - (u64) htab->elem_size * htab->map.max_entries; - - if (cost >= U32_MAX - PAGE_SIZE) - goto free_htab; - - htab->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT; - err = bpf_map_precharge_memlock(htab->map.pages); - if (err) - goto free_htab; - - err = -ENOMEM; - htab->buckets = bpf_map_area_alloc( - htab->n_buckets * sizeof(struct bucket), - htab->map.numa_node); - if (!htab->buckets) - goto free_htab; - - for (i = 0; i < htab->n_buckets; i++) { - INIT_HLIST_HEAD(&htab->buckets[i].head); - raw_spin_lock_init(&htab->buckets[i].lock); - } - - return &htab->map; -free_htab: - kfree(htab); - return ERR_PTR(err); -} - -static void __bpf_htab_free(struct rcu_head *rcu) -{ - struct bpf_htab *htab; - - htab = container_of(rcu, struct bpf_htab, rcu); - bpf_map_area_free(htab->buckets); - kfree(htab); -} - -static void sock_hash_free(struct bpf_map *map) -{ - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - int i; - - synchronize_rcu(); - - /* At this point no update, lookup or delete operations can happen. - * However, be aware we can still get a socket state event updates, - * and data ready callabacks that reference the psock from sk_user_data - * Also psock worker threads are still in-flight. So smap_release_sock - * will only free the psock after cancel_sync on the worker threads - * and a grace period expire to ensure psock is really safe to remove. - */ - rcu_read_lock(); - for (i = 0; i < htab->n_buckets; i++) { - struct bucket *b = __select_bucket(htab, i); - struct hlist_head *head; - struct hlist_node *n; - struct htab_elem *l; - - raw_spin_lock_bh(&b->lock); - head = &b->head; - hlist_for_each_entry_safe(l, n, head, hash_node) { - struct sock *sock = l->sk; - struct smap_psock *psock; - - hlist_del_rcu(&l->hash_node); - psock = smap_psock_sk(sock); - /* This check handles a racing sock event that can get - * the sk_callback_lock before this case but after xchg - * causing the refcnt to hit zero and sock user data - * (psock) to be null and queued for garbage collection. - */ - if (likely(psock)) { - smap_list_hash_remove(psock, l); - smap_release_sock(psock, sock); - } - free_htab_elem(htab, l); - } - raw_spin_unlock_bh(&b->lock); - } - rcu_read_unlock(); - call_rcu(&htab->rcu, __bpf_htab_free); -} - -static struct htab_elem *alloc_sock_hash_elem(struct bpf_htab *htab, - void *key, u32 key_size, u32 hash, - struct sock *sk, - struct htab_elem *old_elem) -{ - struct htab_elem *l_new; - - if (atomic_inc_return(&htab->count) > htab->map.max_entries) { - if (!old_elem) { - atomic_dec(&htab->count); - return ERR_PTR(-E2BIG); - } - } - l_new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN, - htab->map.numa_node); - if (!l_new) { - atomic_dec(&htab->count); - return ERR_PTR(-ENOMEM); - } - - memcpy(l_new->key, key, key_size); - l_new->sk = sk; - l_new->hash = hash; - return l_new; -} - -static inline u32 htab_map_hash(const void *key, u32 key_len) -{ - return jhash(key, key_len, 0); -} - -static int sock_hash_get_next_key(struct bpf_map *map, - void *key, void *next_key) -{ - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - struct htab_elem *l, *next_l; - struct hlist_head *h; - u32 hash, key_size; - int i = 0; - - WARN_ON_ONCE(!rcu_read_lock_held()); - - key_size = map->key_size; - if (!key) - goto find_first_elem; - hash = htab_map_hash(key, key_size); - h = select_bucket(htab, hash); - - l = lookup_elem_raw(h, hash, key, key_size); - if (!l) - goto find_first_elem; - next_l = hlist_entry_safe( - rcu_dereference_raw(hlist_next_rcu(&l->hash_node)), - struct htab_elem, hash_node); - if (next_l) { - memcpy(next_key, next_l->key, key_size); - return 0; - } - - /* no more elements in this hash list, go to the next bucket */ - i = hash & (htab->n_buckets - 1); - i++; - -find_first_elem: - /* iterate over buckets */ - for (; i < htab->n_buckets; i++) { - h = select_bucket(htab, i); - - /* pick first element in the bucket */ - next_l = hlist_entry_safe( - rcu_dereference_raw(hlist_first_rcu(h)), - struct htab_elem, hash_node); - if (next_l) { - /* if it's not empty, just return it */ - memcpy(next_key, next_l->key, key_size); - return 0; - } - } - - /* iterated over all buckets and all elements */ - return -ENOENT; -} - -static int sock_hash_ctx_update_elem(struct bpf_sock_ops_kern *skops, - struct bpf_map *map, - void *key, u64 map_flags) -{ - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - struct bpf_sock_progs *progs = &htab->progs; - struct htab_elem *l_new = NULL, *l_old; - struct smap_psock_map_entry *e = NULL; - struct hlist_head *head; - struct smap_psock *psock; - u32 key_size, hash; - struct sock *sock; - struct bucket *b; - int err; - - sock = skops->sk; - - if (sock->sk_type != SOCK_STREAM || - sock->sk_protocol != IPPROTO_TCP) - return -EOPNOTSUPP; - - if (unlikely(map_flags > BPF_EXIST)) - return -EINVAL; - - e = kzalloc(sizeof(*e), GFP_ATOMIC | __GFP_NOWARN); - if (!e) - return -ENOMEM; - - WARN_ON_ONCE(!rcu_read_lock_held()); - key_size = map->key_size; - hash = htab_map_hash(key, key_size); - b = __select_bucket(htab, hash); - head = &b->head; - - err = __sock_map_ctx_update_elem(map, progs, sock, key); - if (err) - goto err; - - /* psock is valid here because otherwise above *ctx_update_elem would - * have thrown an error. It is safe to skip error check. - */ - psock = smap_psock_sk(sock); - raw_spin_lock_bh(&b->lock); - l_old = lookup_elem_raw(head, hash, key, key_size); - if (l_old && map_flags == BPF_NOEXIST) { - err = -EEXIST; - goto bucket_err; - } - if (!l_old && map_flags == BPF_EXIST) { - err = -ENOENT; - goto bucket_err; - } - - l_new = alloc_sock_hash_elem(htab, key, key_size, hash, sock, l_old); - if (IS_ERR(l_new)) { - err = PTR_ERR(l_new); - goto bucket_err; - } - - rcu_assign_pointer(e->hash_link, l_new); - e->map = map; - spin_lock_bh(&psock->maps_lock); - list_add_tail(&e->list, &psock->maps); - spin_unlock_bh(&psock->maps_lock); - - /* add new element to the head of the list, so that - * concurrent search will find it before old elem - */ - hlist_add_head_rcu(&l_new->hash_node, head); - if (l_old) { - psock = smap_psock_sk(l_old->sk); - - hlist_del_rcu(&l_old->hash_node); - smap_list_hash_remove(psock, l_old); - smap_release_sock(psock, l_old->sk); - free_htab_elem(htab, l_old); - } - raw_spin_unlock_bh(&b->lock); - return 0; -bucket_err: - smap_release_sock(psock, sock); - raw_spin_unlock_bh(&b->lock); -err: - kfree(e); - return err; -} - -static int sock_hash_update_elem(struct bpf_map *map, - void *key, void *value, u64 flags) -{ - struct bpf_sock_ops_kern skops; - u32 fd = *(u32 *)value; - struct socket *socket; - int err; - - socket = sockfd_lookup(fd, &err); - if (!socket) - return err; - - skops.sk = socket->sk; - if (!skops.sk) { - fput(socket->file); - return -EINVAL; - } - - /* ULPs are currently supported only for TCP sockets in ESTABLISHED - * state. - */ - if (skops.sk->sk_type != SOCK_STREAM || - skops.sk->sk_protocol != IPPROTO_TCP || - skops.sk->sk_state != TCP_ESTABLISHED) { - fput(socket->file); - return -EOPNOTSUPP; - } - - lock_sock(skops.sk); - preempt_disable(); - rcu_read_lock(); - err = sock_hash_ctx_update_elem(&skops, map, key, flags); - rcu_read_unlock(); - preempt_enable(); - release_sock(skops.sk); - fput(socket->file); - return err; -} - -static int sock_hash_delete_elem(struct bpf_map *map, void *key) -{ - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - struct hlist_head *head; - struct bucket *b; - struct htab_elem *l; - u32 hash, key_size; - int ret = -ENOENT; - - key_size = map->key_size; - hash = htab_map_hash(key, key_size); - b = __select_bucket(htab, hash); - head = &b->head; - - raw_spin_lock_bh(&b->lock); - l = lookup_elem_raw(head, hash, key, key_size); - if (l) { - struct sock *sock = l->sk; - struct smap_psock *psock; - - hlist_del_rcu(&l->hash_node); - psock = smap_psock_sk(sock); - /* This check handles a racing sock event that can get the - * sk_callback_lock before this case but after xchg happens - * causing the refcnt to hit zero and sock user data (psock) - * to be null and queued for garbage collection. - */ - if (likely(psock)) { - smap_list_hash_remove(psock, l); - smap_release_sock(psock, sock); - } - free_htab_elem(htab, l); - ret = 0; - } - raw_spin_unlock_bh(&b->lock); - return ret; -} - -struct sock *__sock_hash_lookup_elem(struct bpf_map *map, void *key) -{ - struct bpf_htab *htab = container_of(map, struct bpf_htab, map); - struct hlist_head *head; - struct htab_elem *l; - u32 key_size, hash; - struct bucket *b; - struct sock *sk; - - key_size = map->key_size; - hash = htab_map_hash(key, key_size); - b = __select_bucket(htab, hash); - head = &b->head; - - l = lookup_elem_raw(head, hash, key, key_size); - sk = l ? l->sk : NULL; - return sk; -} - -const struct bpf_map_ops sock_map_ops = { - .map_alloc = sock_map_alloc, - .map_free = sock_map_free, - .map_lookup_elem = sock_map_lookup, - .map_get_next_key = sock_map_get_next_key, - .map_update_elem = sock_map_update_elem, - .map_delete_elem = sock_map_delete_elem, - .map_release_uref = sock_map_release, - .map_check_btf = map_check_no_btf, -}; - -const struct bpf_map_ops sock_hash_ops = { - .map_alloc = sock_hash_alloc, - .map_free = sock_hash_free, - .map_lookup_elem = sock_map_lookup, - .map_get_next_key = sock_hash_get_next_key, - .map_update_elem = sock_hash_update_elem, - .map_delete_elem = sock_hash_delete_elem, - .map_release_uref = sock_map_release, - .map_check_btf = map_check_no_btf, -}; - -static bool bpf_is_valid_sock_op(struct bpf_sock_ops_kern *ops) -{ - return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB || - ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB; -} -BPF_CALL_4(bpf_sock_map_update, struct bpf_sock_ops_kern *, bpf_sock, - struct bpf_map *, map, void *, key, u64, flags) -{ - WARN_ON_ONCE(!rcu_read_lock_held()); - - /* ULPs are currently supported only for TCP sockets in ESTABLISHED - * state. This checks that the sock ops triggering the update is - * one indicating we are (or will be soon) in an ESTABLISHED state. - */ - if (!bpf_is_valid_sock_op(bpf_sock)) - return -EOPNOTSUPP; - return sock_map_ctx_update_elem(bpf_sock, map, key, flags); -} - -const struct bpf_func_proto bpf_sock_map_update_proto = { - .func = bpf_sock_map_update, - .gpl_only = false, - .pkt_access = true, - .ret_type = RET_INTEGER, - .arg1_type = ARG_PTR_TO_CTX, - .arg2_type = ARG_CONST_MAP_PTR, - .arg3_type = ARG_PTR_TO_MAP_KEY, - .arg4_type = ARG_ANYTHING, -}; - -BPF_CALL_4(bpf_sock_hash_update, struct bpf_sock_ops_kern *, bpf_sock, - struct bpf_map *, map, void *, key, u64, flags) -{ - WARN_ON_ONCE(!rcu_read_lock_held()); - - if (!bpf_is_valid_sock_op(bpf_sock)) - return -EOPNOTSUPP; - return sock_hash_ctx_update_elem(bpf_sock, map, key, flags); -} - -const struct bpf_func_proto bpf_sock_hash_update_proto = { - .func = bpf_sock_hash_update, - .gpl_only = false, - .pkt_access = true, - .ret_type = RET_INTEGER, - .arg1_type = ARG_PTR_TO_CTX, - .arg2_type = ARG_CONST_MAP_PTR, - .arg3_type = ARG_PTR_TO_MAP_KEY, - .arg4_type = ARG_ANYTHING, -}; diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 8061a439ef18..90daf285de03 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -505,7 +505,7 @@ const struct bpf_func_proto bpf_get_stack_proto = { /* Called from eBPF program */ static void *stack_map_lookup_elem(struct bpf_map *map, void *key) { - return NULL; + return ERR_PTR(-EOPNOTSUPP); } /* Called from syscall */ @@ -600,7 +600,7 @@ static void stack_map_free(struct bpf_map *map) put_callchain_buffers(); } -const struct bpf_map_ops stack_map_ops = { +const struct bpf_map_ops stack_trace_map_ops = { .map_alloc = stack_map_alloc, .map_free = stack_map_free, .map_get_next_key = stack_map_get_next_key, diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 8339d81cba1d..ccb93277aae2 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -30,7 +30,6 @@ #include <linux/cred.h> #include <linux/timekeeping.h> #include <linux/ctype.h> -#include <linux/btf.h> #include <linux/nospec.h> #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \ @@ -652,6 +651,17 @@ int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) return -ENOTSUPP; } +static void *__bpf_copy_key(void __user *ukey, u64 key_size) +{ + if (key_size) + return memdup_user(ukey, key_size); + + if (ukey) + return ERR_PTR(-EINVAL); + + return NULL; +} + /* last field in 'union bpf_attr' used by this command */ #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value @@ -679,7 +689,7 @@ static int map_lookup_elem(union bpf_attr *attr) goto err_put; } - key = memdup_user(ukey, map->key_size); + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); goto err_put; @@ -687,7 +697,8 @@ static int map_lookup_elem(union bpf_attr *attr) if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) + map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || + map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) value_size = round_up(map->value_size, 8) * num_possible_cpus(); else if (IS_FD_MAP(map)) value_size = sizeof(u32); @@ -706,6 +717,8 @@ static int map_lookup_elem(union bpf_attr *attr) err = bpf_percpu_hash_copy(map, key, value); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_copy(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { + err = bpf_percpu_cgroup_storage_copy(map, key, value); } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { err = bpf_stackmap_copy(map, key, value); } else if (IS_FD_ARRAY(map)) { @@ -714,13 +727,21 @@ static int map_lookup_elem(union bpf_attr *attr) err = bpf_fd_htab_map_lookup_elem(map, key, value); } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { err = bpf_fd_reuseport_array_lookup_elem(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_QUEUE || + map->map_type == BPF_MAP_TYPE_STACK) { + err = map->ops->map_peek_elem(map, value); } else { rcu_read_lock(); ptr = map->ops->map_lookup_elem(map, key); - if (ptr) + if (IS_ERR(ptr)) { + err = PTR_ERR(ptr); + } else if (!ptr) { + err = -ENOENT; + } else { + err = 0; memcpy(value, ptr, value_size); + } rcu_read_unlock(); - err = ptr ? 0 : -ENOENT; } if (err) @@ -741,6 +762,17 @@ err_put: return err; } +static void maybe_wait_bpf_programs(struct bpf_map *map) +{ + /* Wait for any running BPF programs to complete so that + * userspace, when we return to it, knows that all programs + * that could be running use the new map value. + */ + if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || + map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) + synchronize_rcu(); +} + #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags static int map_update_elem(union bpf_attr *attr) @@ -767,7 +799,7 @@ static int map_update_elem(union bpf_attr *attr) goto err_put; } - key = memdup_user(ukey, map->key_size); + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); goto err_put; @@ -775,7 +807,8 @@ static int map_update_elem(union bpf_attr *attr) if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) + map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || + map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) value_size = round_up(map->value_size, 8) * num_possible_cpus(); else value_size = map->value_size; @@ -810,6 +843,9 @@ static int map_update_elem(union bpf_attr *attr) err = bpf_percpu_hash_update(map, key, value, attr->flags); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_update(map, key, value, attr->flags); + } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { + err = bpf_percpu_cgroup_storage_update(map, key, value, + attr->flags); } else if (IS_FD_ARRAY(map)) { rcu_read_lock(); err = bpf_fd_array_map_update_elem(map, f.file, key, value, @@ -824,6 +860,9 @@ static int map_update_elem(union bpf_attr *attr) /* rcu_read_lock() is not needed */ err = bpf_fd_reuseport_array_update_elem(map, key, value, attr->flags); + } else if (map->map_type == BPF_MAP_TYPE_QUEUE || + map->map_type == BPF_MAP_TYPE_STACK) { + err = map->ops->map_push_elem(map, value, attr->flags); } else { rcu_read_lock(); err = map->ops->map_update_elem(map, key, value, attr->flags); @@ -831,6 +870,7 @@ static int map_update_elem(union bpf_attr *attr) } __this_cpu_dec(bpf_prog_active); preempt_enable(); + maybe_wait_bpf_programs(map); out: free_value: kfree(value); @@ -865,7 +905,7 @@ static int map_delete_elem(union bpf_attr *attr) goto err_put; } - key = memdup_user(ukey, map->key_size); + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); goto err_put; @@ -883,6 +923,7 @@ static int map_delete_elem(union bpf_attr *attr) rcu_read_unlock(); __this_cpu_dec(bpf_prog_active); preempt_enable(); + maybe_wait_bpf_programs(map); out: kfree(key); err_put: @@ -917,7 +958,7 @@ static int map_get_next_key(union bpf_attr *attr) } if (ukey) { - key = memdup_user(ukey, map->key_size); + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); goto err_put; @@ -958,6 +999,69 @@ err_put: return err; } +#define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value + +static int map_lookup_and_delete_elem(union bpf_attr *attr) +{ + void __user *ukey = u64_to_user_ptr(attr->key); + void __user *uvalue = u64_to_user_ptr(attr->value); + int ufd = attr->map_fd; + struct bpf_map *map; + void *key, *value; + u32 value_size; + struct fd f; + int err; + + if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) + return -EINVAL; + + f = fdget(ufd); + map = __bpf_map_get(f); + if (IS_ERR(map)) + return PTR_ERR(map); + + if (!(f.file->f_mode & FMODE_CAN_WRITE)) { + err = -EPERM; + goto err_put; + } + + key = __bpf_copy_key(ukey, map->key_size); + if (IS_ERR(key)) { + err = PTR_ERR(key); + goto err_put; + } + + value_size = map->value_size; + + err = -ENOMEM; + value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); + if (!value) + goto free_key; + + if (map->map_type == BPF_MAP_TYPE_QUEUE || + map->map_type == BPF_MAP_TYPE_STACK) { + err = map->ops->map_pop_elem(map, value); + } else { + err = -ENOTSUPP; + } + + if (err) + goto free_value; + + if (copy_to_user(uvalue, value, value_size) != 0) + goto free_value; + + err = 0; + +free_value: + kfree(value); +free_key: + kfree(key); +err_put: + fdput(f); + return err; +} + static const struct bpf_prog_ops * const bpf_prog_types[] = { #define BPF_PROG_TYPE(_id, _name) \ [_id] = & _name ## _prog_ops, @@ -989,10 +1093,15 @@ static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) /* drop refcnt on maps used by eBPF program and free auxilary data */ static void free_used_maps(struct bpf_prog_aux *aux) { + enum bpf_cgroup_storage_type stype; int i; - if (aux->cgroup_storage) - bpf_cgroup_storage_release(aux->prog, aux->cgroup_storage); + for_each_cgroup_storage_type(stype) { + if (!aux->cgroup_storage[stype]) + continue; + bpf_cgroup_storage_release(aux->prog, + aux->cgroup_storage[stype]); + } for (i = 0; i < aux->used_map_cnt; i++) bpf_map_put(aux->used_maps[i]); @@ -1616,6 +1725,9 @@ static int bpf_prog_attach(const union bpf_attr *attr) case BPF_LIRC_MODE2: ptype = BPF_PROG_TYPE_LIRC_MODE2; break; + case BPF_FLOW_DISSECTOR: + ptype = BPF_PROG_TYPE_FLOW_DISSECTOR; + break; default: return -EINVAL; } @@ -1632,11 +1744,14 @@ static int bpf_prog_attach(const union bpf_attr *attr) switch (ptype) { case BPF_PROG_TYPE_SK_SKB: case BPF_PROG_TYPE_SK_MSG: - ret = sockmap_get_from_fd(attr, ptype, prog); + ret = sock_map_get_from_fd(attr, prog); break; case BPF_PROG_TYPE_LIRC_MODE2: ret = lirc_prog_attach(attr, prog); break; + case BPF_PROG_TYPE_FLOW_DISSECTOR: + ret = skb_flow_dissector_bpf_prog_attach(attr, prog); + break; default: ret = cgroup_bpf_prog_attach(attr, ptype, prog); } @@ -1683,12 +1798,14 @@ static int bpf_prog_detach(const union bpf_attr *attr) ptype = BPF_PROG_TYPE_CGROUP_DEVICE; break; case BPF_SK_MSG_VERDICT: - return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_MSG, NULL); + return sock_map_get_from_fd(attr, NULL); case BPF_SK_SKB_STREAM_PARSER: case BPF_SK_SKB_STREAM_VERDICT: - return sockmap_get_from_fd(attr, BPF_PROG_TYPE_SK_SKB, NULL); + return sock_map_get_from_fd(attr, NULL); case BPF_LIRC_MODE2: return lirc_prog_detach(attr); + case BPF_FLOW_DISSECTOR: + return skb_flow_dissector_bpf_prog_detach(attr); default: return -EINVAL; } @@ -2418,6 +2535,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz case BPF_TASK_FD_QUERY: err = bpf_task_fd_query(&attr, uattr); break; + case BPF_MAP_LOOKUP_AND_DELETE_ELEM: + err = map_lookup_and_delete_elem(&attr); + break; default: err = -EINVAL; break; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 465952a8e465..98fa0be35370 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1,5 +1,6 @@ /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com * Copyright (c) 2016 Facebook + * Copyright (c) 2018 Covalent IO, Inc. http://covalent.io * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public @@ -80,8 +81,8 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = { * (like pointer plus pointer becomes SCALAR_VALUE type) * * When verifier sees load or store instructions the type of base register - * can be: PTR_TO_MAP_VALUE, PTR_TO_CTX, PTR_TO_STACK. These are three pointer - * types recognized by check_mem_access() function. + * can be: PTR_TO_MAP_VALUE, PTR_TO_CTX, PTR_TO_STACK, PTR_TO_SOCKET. These are + * four pointer types recognized by check_mem_access() function. * * PTR_TO_MAP_VALUE means that this register is pointing to 'map element value' * and the range of [ptr, ptr + map's value_size) is accessible. @@ -140,6 +141,24 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = { * * After the call R0 is set to return type of the function and registers R1-R5 * are set to NOT_INIT to indicate that they are no longer readable. + * + * The following reference types represent a potential reference to a kernel + * resource which, after first being allocated, must be checked and freed by + * the BPF program: + * - PTR_TO_SOCKET_OR_NULL, PTR_TO_SOCKET + * + * When the verifier sees a helper call return a reference type, it allocates a + * pointer id for the reference and stores it in the current function state. + * Similar to the way that PTR_TO_MAP_VALUE_OR_NULL is converted into + * PTR_TO_MAP_VALUE, PTR_TO_SOCKET_OR_NULL becomes PTR_TO_SOCKET when the type + * passes through a NULL-check conditional. For the branch wherein the state is + * changed to CONST_IMM, the verifier releases the reference. + * + * For each helper function that allocates a reference, such as + * bpf_sk_lookup_tcp(), there is a corresponding release function, such as + * bpf_sk_release(). When a reference type passes into the release function, + * the verifier also releases the reference. If any unchecked or unreleased + * reference remains at the end of the program, the verifier rejects it. */ /* verifier_state + insn_idx are pushed to stack when branch is encountered */ @@ -189,6 +208,7 @@ struct bpf_call_arg_meta { int access_size; s64 msize_smax_value; u64 msize_umax_value; + int ptr_id; }; static DEFINE_MUTEX(bpf_verifier_lock); @@ -249,6 +269,46 @@ static bool type_is_pkt_pointer(enum bpf_reg_type type) type == PTR_TO_PACKET_META; } +static bool reg_type_may_be_null(enum bpf_reg_type type) +{ + return type == PTR_TO_MAP_VALUE_OR_NULL || + type == PTR_TO_SOCKET_OR_NULL; +} + +static bool type_is_refcounted(enum bpf_reg_type type) +{ + return type == PTR_TO_SOCKET; +} + +static bool type_is_refcounted_or_null(enum bpf_reg_type type) +{ + return type == PTR_TO_SOCKET || type == PTR_TO_SOCKET_OR_NULL; +} + +static bool reg_is_refcounted(const struct bpf_reg_state *reg) +{ + return type_is_refcounted(reg->type); +} + +static bool reg_is_refcounted_or_null(const struct bpf_reg_state *reg) +{ + return type_is_refcounted_or_null(reg->type); +} + +static bool arg_type_is_refcounted(enum bpf_arg_type type) +{ + return type == ARG_PTR_TO_SOCKET; +} + +/* Determine whether the function releases some resources allocated by another + * function call. The first reference type argument will be assumed to be + * released by release_reference(). + */ +static bool is_release_function(enum bpf_func_id func_id) +{ + return func_id == BPF_FUNC_sk_release; +} + /* string representation of 'enum bpf_reg_type' */ static const char * const reg_type_str[] = { [NOT_INIT] = "?", @@ -261,6 +321,16 @@ static const char * const reg_type_str[] = { [PTR_TO_PACKET] = "pkt", [PTR_TO_PACKET_META] = "pkt_meta", [PTR_TO_PACKET_END] = "pkt_end", + [PTR_TO_FLOW_KEYS] = "flow_keys", + [PTR_TO_SOCKET] = "sock", + [PTR_TO_SOCKET_OR_NULL] = "sock_or_null", +}; + +static char slot_type_char[] = { + [STACK_INVALID] = '?', + [STACK_SPILL] = 'r', + [STACK_MISC] = 'm', + [STACK_ZERO] = '0', }; static void print_liveness(struct bpf_verifier_env *env, @@ -349,72 +419,179 @@ static void print_verifier_state(struct bpf_verifier_env *env, } } for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] == STACK_SPILL) { - verbose(env, " fp%d", - (-i - 1) * BPF_REG_SIZE); - print_liveness(env, state->stack[i].spilled_ptr.live); + char types_buf[BPF_REG_SIZE + 1]; + bool valid = false; + int j; + + for (j = 0; j < BPF_REG_SIZE; j++) { + if (state->stack[i].slot_type[j] != STACK_INVALID) + valid = true; + types_buf[j] = slot_type_char[ + state->stack[i].slot_type[j]]; + } + types_buf[BPF_REG_SIZE] = 0; + if (!valid) + continue; + verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE); + print_liveness(env, state->stack[i].spilled_ptr.live); + if (state->stack[i].slot_type[0] == STACK_SPILL) verbose(env, "=%s", reg_type_str[state->stack[i].spilled_ptr.type]); - } - if (state->stack[i].slot_type[0] == STACK_ZERO) - verbose(env, " fp%d=0", (-i - 1) * BPF_REG_SIZE); + else + verbose(env, "=%s", types_buf); + } + if (state->acquired_refs && state->refs[0].id) { + verbose(env, " refs=%d", state->refs[0].id); + for (i = 1; i < state->acquired_refs; i++) + if (state->refs[i].id) + verbose(env, ",%d", state->refs[i].id); } verbose(env, "\n"); } -static int copy_stack_state(struct bpf_func_state *dst, - const struct bpf_func_state *src) -{ - if (!src->stack) - return 0; - if (WARN_ON_ONCE(dst->allocated_stack < src->allocated_stack)) { - /* internal bug, make state invalid to reject the program */ - memset(dst, 0, sizeof(*dst)); - return -EFAULT; - } - memcpy(dst->stack, src->stack, - sizeof(*src->stack) * (src->allocated_stack / BPF_REG_SIZE)); - return 0; -} +#define COPY_STATE_FN(NAME, COUNT, FIELD, SIZE) \ +static int copy_##NAME##_state(struct bpf_func_state *dst, \ + const struct bpf_func_state *src) \ +{ \ + if (!src->FIELD) \ + return 0; \ + if (WARN_ON_ONCE(dst->COUNT < src->COUNT)) { \ + /* internal bug, make state invalid to reject the program */ \ + memset(dst, 0, sizeof(*dst)); \ + return -EFAULT; \ + } \ + memcpy(dst->FIELD, src->FIELD, \ + sizeof(*src->FIELD) * (src->COUNT / SIZE)); \ + return 0; \ +} +/* copy_reference_state() */ +COPY_STATE_FN(reference, acquired_refs, refs, 1) +/* copy_stack_state() */ +COPY_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE) +#undef COPY_STATE_FN + +#define REALLOC_STATE_FN(NAME, COUNT, FIELD, SIZE) \ +static int realloc_##NAME##_state(struct bpf_func_state *state, int size, \ + bool copy_old) \ +{ \ + u32 old_size = state->COUNT; \ + struct bpf_##NAME##_state *new_##FIELD; \ + int slot = size / SIZE; \ + \ + if (size <= old_size || !size) { \ + if (copy_old) \ + return 0; \ + state->COUNT = slot * SIZE; \ + if (!size && old_size) { \ + kfree(state->FIELD); \ + state->FIELD = NULL; \ + } \ + return 0; \ + } \ + new_##FIELD = kmalloc_array(slot, sizeof(struct bpf_##NAME##_state), \ + GFP_KERNEL); \ + if (!new_##FIELD) \ + return -ENOMEM; \ + if (copy_old) { \ + if (state->FIELD) \ + memcpy(new_##FIELD, state->FIELD, \ + sizeof(*new_##FIELD) * (old_size / SIZE)); \ + memset(new_##FIELD + old_size / SIZE, 0, \ + sizeof(*new_##FIELD) * (size - old_size) / SIZE); \ + } \ + state->COUNT = slot * SIZE; \ + kfree(state->FIELD); \ + state->FIELD = new_##FIELD; \ + return 0; \ +} +/* realloc_reference_state() */ +REALLOC_STATE_FN(reference, acquired_refs, refs, 1) +/* realloc_stack_state() */ +REALLOC_STATE_FN(stack, allocated_stack, stack, BPF_REG_SIZE) +#undef REALLOC_STATE_FN /* do_check() starts with zero-sized stack in struct bpf_verifier_state to * make it consume minimal amount of memory. check_stack_write() access from * the program calls into realloc_func_state() to grow the stack size. * Note there is a non-zero 'parent' pointer inside bpf_verifier_state - * which this function copies over. It points to previous bpf_verifier_state - * which is never reallocated + * which realloc_stack_state() copies over. It points to previous + * bpf_verifier_state which is never reallocated. */ -static int realloc_func_state(struct bpf_func_state *state, int size, - bool copy_old) +static int realloc_func_state(struct bpf_func_state *state, int stack_size, + int refs_size, bool copy_old) { - u32 old_size = state->allocated_stack; - struct bpf_stack_state *new_stack; - int slot = size / BPF_REG_SIZE; + int err = realloc_reference_state(state, refs_size, copy_old); + if (err) + return err; + return realloc_stack_state(state, stack_size, copy_old); +} + +/* Acquire a pointer id from the env and update the state->refs to include + * this new pointer reference. + * On success, returns a valid pointer id to associate with the register + * On failure, returns a negative errno. + */ +static int acquire_reference_state(struct bpf_verifier_env *env, int insn_idx) +{ + struct bpf_func_state *state = cur_func(env); + int new_ofs = state->acquired_refs; + int id, err; - if (size <= old_size || !size) { - if (copy_old) + err = realloc_reference_state(state, state->acquired_refs + 1, true); + if (err) + return err; + id = ++env->id_gen; + state->refs[new_ofs].id = id; + state->refs[new_ofs].insn_idx = insn_idx; + + return id; +} + +/* release function corresponding to acquire_reference_state(). Idempotent. */ +static int __release_reference_state(struct bpf_func_state *state, int ptr_id) +{ + int i, last_idx; + + if (!ptr_id) + return -EFAULT; + + last_idx = state->acquired_refs - 1; + for (i = 0; i < state->acquired_refs; i++) { + if (state->refs[i].id == ptr_id) { + if (last_idx && i != last_idx) + memcpy(&state->refs[i], &state->refs[last_idx], + sizeof(*state->refs)); + memset(&state->refs[last_idx], 0, sizeof(*state->refs)); + state->acquired_refs--; return 0; - state->allocated_stack = slot * BPF_REG_SIZE; - if (!size && old_size) { - kfree(state->stack); - state->stack = NULL; } - return 0; } - new_stack = kmalloc_array(slot, sizeof(struct bpf_stack_state), - GFP_KERNEL); - if (!new_stack) - return -ENOMEM; - if (copy_old) { - if (state->stack) - memcpy(new_stack, state->stack, - sizeof(*new_stack) * (old_size / BPF_REG_SIZE)); - memset(new_stack + old_size / BPF_REG_SIZE, 0, - sizeof(*new_stack) * (size - old_size) / BPF_REG_SIZE); - } - state->allocated_stack = slot * BPF_REG_SIZE; - kfree(state->stack); - state->stack = new_stack; + return -EFAULT; +} + +/* variation on the above for cases where we expect that there must be an + * outstanding reference for the specified ptr_id. + */ +static int release_reference_state(struct bpf_verifier_env *env, int ptr_id) +{ + struct bpf_func_state *state = cur_func(env); + int err; + + err = __release_reference_state(state, ptr_id); + if (WARN_ON_ONCE(err != 0)) + verbose(env, "verifier internal error: can't release reference\n"); + return err; +} + +static int transfer_reference_state(struct bpf_func_state *dst, + struct bpf_func_state *src) +{ + int err = realloc_reference_state(dst, src->acquired_refs, false); + if (err) + return err; + err = copy_reference_state(dst, src); + if (err) + return err; return 0; } @@ -422,6 +599,7 @@ static void free_func_state(struct bpf_func_state *state) { if (!state) return; + kfree(state->refs); kfree(state->stack); kfree(state); } @@ -447,10 +625,14 @@ static int copy_func_state(struct bpf_func_state *dst, { int err; - err = realloc_func_state(dst, src->allocated_stack, false); + err = realloc_func_state(dst, src->allocated_stack, src->acquired_refs, + false); + if (err) + return err; + memcpy(dst, src, offsetof(struct bpf_func_state, acquired_refs)); + err = copy_reference_state(dst, src); if (err) return err; - memcpy(dst, src, offsetof(struct bpf_func_state, allocated_stack)); return copy_stack_state(dst, src); } @@ -466,7 +648,6 @@ static int copy_verifier_state(struct bpf_verifier_state *dst_state, dst_state->frame[i] = NULL; } dst_state->curframe = src->curframe; - dst_state->parent = src->parent; for (i = 0; i <= src->curframe; i++) { dst = dst_state->frame[i]; if (!dst) { @@ -553,7 +734,9 @@ static void __mark_reg_not_init(struct bpf_reg_state *reg); */ static void __mark_reg_known(struct bpf_reg_state *reg, u64 imm) { - reg->id = 0; + /* Clear id, off, and union(map_ptr, range) */ + memset(((u8 *)reg) + sizeof(reg->type), 0, + offsetof(struct bpf_reg_state, var_off) - sizeof(reg->type)); reg->var_off = tnum_const(imm); reg->smin_value = (s64)imm; reg->smax_value = (s64)imm; @@ -572,7 +755,6 @@ static void __mark_reg_known_zero(struct bpf_reg_state *reg) static void __mark_reg_const_zero(struct bpf_reg_state *reg) { __mark_reg_known(reg, 0); - reg->off = 0; reg->type = SCALAR_VALUE; } @@ -683,9 +865,12 @@ static void __mark_reg_unbounded(struct bpf_reg_state *reg) /* Mark a register as having a completely unknown (scalar) value. */ static void __mark_reg_unknown(struct bpf_reg_state *reg) { + /* + * Clear type, id, off, and union(map_ptr, range) and + * padding between 'type' and union + */ + memset(reg, 0, offsetof(struct bpf_reg_state, var_off)); reg->type = SCALAR_VALUE; - reg->id = 0; - reg->off = 0; reg->var_off = tnum_unknown; reg->frameno = 0; __mark_reg_unbounded(reg); @@ -732,6 +917,7 @@ static void init_reg_state(struct bpf_verifier_env *env, for (i = 0; i < MAX_BPF_REG; i++) { mark_reg_not_init(env, regs, i); regs[i].live = REG_LIVE_NONE; + regs[i].parent = NULL; } /* frame pointer */ @@ -823,10 +1009,6 @@ static int check_subprogs(struct bpf_verifier_env *env) verbose(env, "function calls to other bpf functions are allowed for root only\n"); return -EPERM; } - if (bpf_prog_is_dev_bound(env->prog->aux)) { - verbose(env, "function calls in offloaded programs are not supported yet\n"); - return -EINVAL; - } ret = add_subprog(env, i + insn[i].imm + 1); if (ret < 0) return ret; @@ -876,74 +1058,21 @@ next: return 0; } -static -struct bpf_verifier_state *skip_callee(struct bpf_verifier_env *env, - const struct bpf_verifier_state *state, - struct bpf_verifier_state *parent, - u32 regno) -{ - struct bpf_verifier_state *tmp = NULL; - - /* 'parent' could be a state of caller and - * 'state' could be a state of callee. In such case - * parent->curframe < state->curframe - * and it's ok for r1 - r5 registers - * - * 'parent' could be a callee's state after it bpf_exit-ed. - * In such case parent->curframe > state->curframe - * and it's ok for r0 only - */ - if (parent->curframe == state->curframe || - (parent->curframe < state->curframe && - regno >= BPF_REG_1 && regno <= BPF_REG_5) || - (parent->curframe > state->curframe && - regno == BPF_REG_0)) - return parent; - - if (parent->curframe > state->curframe && - regno >= BPF_REG_6) { - /* for callee saved regs we have to skip the whole chain - * of states that belong to callee and mark as LIVE_READ - * the registers before the call - */ - tmp = parent; - while (tmp && tmp->curframe != state->curframe) { - tmp = tmp->parent; - } - if (!tmp) - goto bug; - parent = tmp; - } else { - goto bug; - } - return parent; -bug: - verbose(env, "verifier bug regno %d tmp %p\n", regno, tmp); - verbose(env, "regno %d parent frame %d current frame %d\n", - regno, parent->curframe, state->curframe); - return NULL; -} - +/* Parentage chain of this register (or stack slot) should take care of all + * issues like callee-saved registers, stack slot allocation time, etc. + */ static int mark_reg_read(struct bpf_verifier_env *env, - const struct bpf_verifier_state *state, - struct bpf_verifier_state *parent, - u32 regno) + const struct bpf_reg_state *state, + struct bpf_reg_state *parent) { bool writes = parent == state->parent; /* Observe write marks */ - if (regno == BPF_REG_FP) - /* We don't need to worry about FP liveness because it's read-only */ - return 0; - while (parent) { /* if read wasn't screened by an earlier write ... */ - if (writes && state->frame[state->curframe]->regs[regno].live & REG_LIVE_WRITTEN) + if (writes && state->live & REG_LIVE_WRITTEN) break; - parent = skip_callee(env, state, parent, regno); - if (!parent) - return -EFAULT; /* ... then we depend on parent's value */ - parent->frame[parent->curframe]->regs[regno].live |= REG_LIVE_READ; + parent->live |= REG_LIVE_READ; state = parent; parent = state->parent; writes = true; @@ -969,7 +1098,10 @@ static int check_reg_arg(struct bpf_verifier_env *env, u32 regno, verbose(env, "R%d !read_ok\n", regno); return -EACCES; } - return mark_reg_read(env, vstate, vstate->parent, regno); + /* We don't need to worry about FP liveness because it's read-only */ + if (regno != BPF_REG_FP) + return mark_reg_read(env, ®s[regno], + regs[regno].parent); } else { /* check whether register used as dest operand can be written to */ if (regno == BPF_REG_FP) { @@ -993,7 +1125,10 @@ static bool is_spillable_regtype(enum bpf_reg_type type) case PTR_TO_PACKET: case PTR_TO_PACKET_META: case PTR_TO_PACKET_END: + case PTR_TO_FLOW_KEYS: case CONST_PTR_TO_MAP: + case PTR_TO_SOCKET: + case PTR_TO_SOCKET_OR_NULL: return true; default: return false; @@ -1018,7 +1153,7 @@ static int check_stack_write(struct bpf_verifier_env *env, enum bpf_reg_type type; err = realloc_func_state(state, round_up(slot + 1, BPF_REG_SIZE), - true); + state->acquired_refs, true); if (err) return err; /* caller checked that off % size == 0 and -MAX_BPF_STACK <= off < 0, @@ -1080,8 +1215,8 @@ static int check_stack_write(struct bpf_verifier_env *env, } else { u8 type = STACK_MISC; - /* regular write of data into stack */ - state->stack[spi].spilled_ptr = (struct bpf_reg_state) {}; + /* regular write of data into stack destroys any spilled ptr */ + state->stack[spi].spilled_ptr.type = NOT_INIT; /* only mark the slot as written if all 8 bytes were written * otherwise read propagation may incorrectly stop too soon @@ -1106,61 +1241,6 @@ static int check_stack_write(struct bpf_verifier_env *env, return 0; } -/* registers of every function are unique and mark_reg_read() propagates - * the liveness in the following cases: - * - from callee into caller for R1 - R5 that were used as arguments - * - from caller into callee for R0 that used as result of the call - * - from caller to the same caller skipping states of the callee for R6 - R9, - * since R6 - R9 are callee saved by implicit function prologue and - * caller's R6 != callee's R6, so when we propagate liveness up to - * parent states we need to skip callee states for R6 - R9. - * - * stack slot marking is different, since stacks of caller and callee are - * accessible in both (since caller can pass a pointer to caller's stack to - * callee which can pass it to another function), hence mark_stack_slot_read() - * has to propagate the stack liveness to all parent states at given frame number. - * Consider code: - * f1() { - * ptr = fp - 8; - * *ptr = ctx; - * call f2 { - * .. = *ptr; - * } - * .. = *ptr; - * } - * First *ptr is reading from f1's stack and mark_stack_slot_read() has - * to mark liveness at the f1's frame and not f2's frame. - * Second *ptr is also reading from f1's stack and mark_stack_slot_read() has - * to propagate liveness to f2 states at f1's frame level and further into - * f1 states at f1's frame level until write into that stack slot - */ -static void mark_stack_slot_read(struct bpf_verifier_env *env, - const struct bpf_verifier_state *state, - struct bpf_verifier_state *parent, - int slot, int frameno) -{ - bool writes = parent == state->parent; /* Observe write marks */ - - while (parent) { - if (parent->frame[frameno]->allocated_stack <= slot * BPF_REG_SIZE) - /* since LIVE_WRITTEN mark is only done for full 8-byte - * write the read marks are conservative and parent - * state may not even have the stack allocated. In such case - * end the propagation, since the loop reached beginning - * of the function - */ - break; - /* if read wasn't screened by an earlier write ... */ - if (writes && state->frame[frameno]->stack[slot].spilled_ptr.live & REG_LIVE_WRITTEN) - break; - /* ... then we depend on parent's value */ - parent->frame[frameno]->stack[slot].spilled_ptr.live |= REG_LIVE_READ; - state = parent; - parent = state->parent; - writes = true; - } -} - static int check_stack_read(struct bpf_verifier_env *env, struct bpf_func_state *reg_state /* func where register points to */, int off, int size, int value_regno) @@ -1198,8 +1278,8 @@ static int check_stack_read(struct bpf_verifier_env *env, */ state->regs[value_regno].live |= REG_LIVE_WRITTEN; } - mark_stack_slot_read(env, vstate, vstate->parent, spi, - reg_state->frameno); + mark_reg_read(env, ®_state->stack[spi].spilled_ptr, + reg_state->stack[spi].spilled_ptr.parent); return 0; } else { int zeros = 0; @@ -1215,8 +1295,8 @@ static int check_stack_read(struct bpf_verifier_env *env, off, i, size); return -EACCES; } - mark_stack_slot_read(env, vstate, vstate->parent, spi, - reg_state->frameno); + mark_reg_read(env, ®_state->stack[spi].spilled_ptr, + reg_state->stack[spi].spilled_ptr.parent); if (value_regno >= 0) { if (zeros == size) { /* any size read into register is zero extended, @@ -1321,6 +1401,7 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env, case BPF_PROG_TYPE_LWT_XMIT: case BPF_PROG_TYPE_SK_SKB: case BPF_PROG_TYPE_SK_MSG: + case BPF_PROG_TYPE_FLOW_DISSECTOR: if (meta) return meta->pkt_access; @@ -1404,6 +1485,40 @@ static int check_ctx_access(struct bpf_verifier_env *env, int insn_idx, int off, return -EACCES; } +static int check_flow_keys_access(struct bpf_verifier_env *env, int off, + int size) +{ + if (size < 0 || off < 0 || + (u64)off + size > sizeof(struct bpf_flow_keys)) { + verbose(env, "invalid access to flow keys off=%d size=%d\n", + off, size); + return -EACCES; + } + return 0; +} + +static int check_sock_access(struct bpf_verifier_env *env, u32 regno, int off, + int size, enum bpf_access_type t) +{ + struct bpf_reg_state *regs = cur_regs(env); + struct bpf_reg_state *reg = ®s[regno]; + struct bpf_insn_access_aux info; + + if (reg->smin_value < 0) { + verbose(env, "R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n", + regno); + return -EACCES; + } + + if (!bpf_sock_is_valid_access(off, size, t, &info)) { + verbose(env, "invalid bpf_sock access off=%d size=%d\n", + off, size); + return -EACCES; + } + + return 0; +} + static bool __is_pointer_value(bool allow_ptr_leaks, const struct bpf_reg_state *reg) { @@ -1413,25 +1528,39 @@ static bool __is_pointer_value(bool allow_ptr_leaks, return reg->type != SCALAR_VALUE; } +static struct bpf_reg_state *reg_state(struct bpf_verifier_env *env, int regno) +{ + return cur_regs(env) + regno; +} + static bool is_pointer_value(struct bpf_verifier_env *env, int regno) { - return __is_pointer_value(env->allow_ptr_leaks, cur_regs(env) + regno); + return __is_pointer_value(env->allow_ptr_leaks, reg_state(env, regno)); } static bool is_ctx_reg(struct bpf_verifier_env *env, int regno) { - const struct bpf_reg_state *reg = cur_regs(env) + regno; + const struct bpf_reg_state *reg = reg_state(env, regno); - return reg->type == PTR_TO_CTX; + return reg->type == PTR_TO_CTX || + reg->type == PTR_TO_SOCKET; } static bool is_pkt_reg(struct bpf_verifier_env *env, int regno) { - const struct bpf_reg_state *reg = cur_regs(env) + regno; + const struct bpf_reg_state *reg = reg_state(env, regno); return type_is_pkt_pointer(reg->type); } +static bool is_flow_key_reg(struct bpf_verifier_env *env, int regno) +{ + const struct bpf_reg_state *reg = reg_state(env, regno); + + /* Separate to is_ctx_reg() since we still want to allow BPF_ST here. */ + return reg->type == PTR_TO_FLOW_KEYS; +} + static int check_pkt_ptr_alignment(struct bpf_verifier_env *env, const struct bpf_reg_state *reg, int off, int size, bool strict) @@ -1505,6 +1634,9 @@ static int check_ptr_alignment(struct bpf_verifier_env *env, * right in front, treat it the very same way. */ return check_pkt_ptr_alignment(env, reg, off, size, strict); + case PTR_TO_FLOW_KEYS: + pointer_desc = "flow keys "; + break; case PTR_TO_MAP_VALUE: pointer_desc = "value "; break; @@ -1519,6 +1651,9 @@ static int check_ptr_alignment(struct bpf_verifier_env *env, */ strict = true; break; + case PTR_TO_SOCKET: + pointer_desc = "sock "; + break; default: break; } @@ -1727,9 +1862,6 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn else mark_reg_known_zero(env, regs, value_regno); - regs[value_regno].id = 0; - regs[value_regno].off = 0; - regs[value_regno].range = 0; regs[value_regno].type = reg_type; } @@ -1778,6 +1910,25 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn err = check_packet_access(env, regno, off, size, false); if (!err && t == BPF_READ && value_regno >= 0) mark_reg_unknown(env, regs, value_regno); + } else if (reg->type == PTR_TO_FLOW_KEYS) { + if (t == BPF_WRITE && value_regno >= 0 && + is_pointer_value(env, value_regno)) { + verbose(env, "R%d leaks addr into flow keys\n", + value_regno); + return -EACCES; + } + + err = check_flow_keys_access(env, off, size); + if (!err && t == BPF_READ && value_regno >= 0) + mark_reg_unknown(env, regs, value_regno); + } else if (reg->type == PTR_TO_SOCKET) { + if (t == BPF_WRITE) { + verbose(env, "cannot write into socket\n"); + return -EACCES; + } + err = check_sock_access(env, regno, off, size, t); + if (!err && value_regno >= 0) + mark_reg_unknown(env, regs, value_regno); } else { verbose(env, "R%d invalid mem access '%s'\n", regno, reg_type_str[reg->type]); @@ -1818,10 +1969,11 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins } if (is_ctx_reg(env, insn->dst_reg) || - is_pkt_reg(env, insn->dst_reg)) { + is_pkt_reg(env, insn->dst_reg) || + is_flow_key_reg(env, insn->dst_reg)) { verbose(env, "BPF_XADD stores into R%d %s is not allowed\n", - insn->dst_reg, is_ctx_reg(env, insn->dst_reg) ? - "context" : "packet"); + insn->dst_reg, + reg_type_str[reg_state(env, insn->dst_reg)->type]); return -EACCES; } @@ -1846,7 +1998,7 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno, int access_size, bool zero_size_allowed, struct bpf_call_arg_meta *meta) { - struct bpf_reg_state *reg = cur_regs(env) + regno; + struct bpf_reg_state *reg = reg_state(env, regno); struct bpf_func_state *state = func(env, reg); int off, i, slot, spi; @@ -1908,8 +2060,8 @@ mark: /* reading any byte out of 8-byte 'spill_slot' will cause * the whole slot to be marked as 'read' */ - mark_stack_slot_read(env, env->cur_state, env->cur_state->parent, - spi, state->frameno); + mark_reg_read(env, &state->stack[spi].spilled_ptr, + state->stack[spi].spilled_ptr.parent); } return update_stack_depth(env, state, off); } @@ -1978,7 +2130,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, } if (arg_type == ARG_PTR_TO_MAP_KEY || - arg_type == ARG_PTR_TO_MAP_VALUE) { + arg_type == ARG_PTR_TO_MAP_VALUE || + arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE) { expected_type = PTR_TO_STACK; if (!type_is_pkt_pointer(type) && type != PTR_TO_MAP_VALUE && type != expected_type) @@ -1999,6 +2152,16 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, err = check_ctx_reg(env, reg, regno); if (err < 0) return err; + } else if (arg_type == ARG_PTR_TO_SOCKET) { + expected_type = PTR_TO_SOCKET; + if (type != expected_type) + goto err_type; + if (meta->ptr_id || !reg->id) { + verbose(env, "verifier internal error: mismatched references meta=%d, reg=%d\n", + meta->ptr_id, reg->id); + return -EFAULT; + } + meta->ptr_id = reg->id; } else if (arg_type_is_mem_ptr(arg_type)) { expected_type = PTR_TO_STACK; /* One exception here. In case function allows for NULL to be @@ -2038,7 +2201,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, err = check_helper_mem_access(env, regno, meta->map_ptr->key_size, false, NULL); - } else if (arg_type == ARG_PTR_TO_MAP_VALUE) { + } else if (arg_type == ARG_PTR_TO_MAP_VALUE || + arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE) { /* bpf_map_xxx(..., map_ptr, ..., value) call: * check [value, value + map->value_size) validity */ @@ -2047,9 +2211,10 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, verbose(env, "invalid map_ptr to access map->value\n"); return -EACCES; } + meta->raw_mode = (arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE); err = check_helper_mem_access(env, regno, meta->map_ptr->value_size, false, - NULL); + meta); } else if (arg_type_is_mem_size(arg_type)) { bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO); @@ -2129,6 +2294,7 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, goto error; break; case BPF_MAP_TYPE_CGROUP_STORAGE: + case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: if (func_id != BPF_FUNC_get_local_storage) goto error; break; @@ -2171,6 +2337,13 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, if (func_id != BPF_FUNC_sk_select_reuseport) goto error; break; + case BPF_MAP_TYPE_QUEUE: + case BPF_MAP_TYPE_STACK: + if (func_id != BPF_FUNC_map_peek_elem && + func_id != BPF_FUNC_map_pop_elem && + func_id != BPF_FUNC_map_push_elem) + goto error; + break; default: break; } @@ -2219,13 +2392,21 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, goto error; break; case BPF_FUNC_get_local_storage: - if (map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE) + if (map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && + map->map_type != BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) goto error; break; case BPF_FUNC_sk_select_reuseport: if (map->map_type != BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) goto error; break; + case BPF_FUNC_map_peek_elem: + case BPF_FUNC_map_pop_elem: + case BPF_FUNC_map_push_elem: + if (map->map_type != BPF_MAP_TYPE_QUEUE && + map->map_type != BPF_MAP_TYPE_STACK) + goto error; + break; default: break; } @@ -2286,10 +2467,32 @@ static bool check_arg_pair_ok(const struct bpf_func_proto *fn) return true; } +static bool check_refcount_ok(const struct bpf_func_proto *fn) +{ + int count = 0; + + if (arg_type_is_refcounted(fn->arg1_type)) + count++; + if (arg_type_is_refcounted(fn->arg2_type)) + count++; + if (arg_type_is_refcounted(fn->arg3_type)) + count++; + if (arg_type_is_refcounted(fn->arg4_type)) + count++; + if (arg_type_is_refcounted(fn->arg5_type)) + count++; + + /* We only support one arg being unreferenced at the moment, + * which is sufficient for the helper functions we have right now. + */ + return count <= 1; +} + static int check_func_proto(const struct bpf_func_proto *fn) { return check_raw_mode_ok(fn) && - check_arg_pair_ok(fn) ? 0 : -EINVAL; + check_arg_pair_ok(fn) && + check_refcount_ok(fn) ? 0 : -EINVAL; } /* Packet data might have moved, any old PTR_TO_PACKET[_META,_END] @@ -2305,10 +2508,9 @@ static void __clear_all_pkt_pointers(struct bpf_verifier_env *env, if (reg_is_pkt_pointer_any(®s[i])) mark_reg_unknown(env, regs, i); - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) + bpf_for_each_spilled_reg(i, state, reg) { + if (!reg) continue; - reg = &state->stack[i].spilled_ptr; if (reg_is_pkt_pointer_any(reg)) __mark_reg_unknown(reg); } @@ -2323,12 +2525,45 @@ static void clear_all_pkt_pointers(struct bpf_verifier_env *env) __clear_all_pkt_pointers(env, vstate->frame[i]); } +static void release_reg_references(struct bpf_verifier_env *env, + struct bpf_func_state *state, int id) +{ + struct bpf_reg_state *regs = state->regs, *reg; + int i; + + for (i = 0; i < MAX_BPF_REG; i++) + if (regs[i].id == id) + mark_reg_unknown(env, regs, i); + + bpf_for_each_spilled_reg(i, state, reg) { + if (!reg) + continue; + if (reg_is_refcounted(reg) && reg->id == id) + __mark_reg_unknown(reg); + } +} + +/* The pointer with the specified id has released its reference to kernel + * resources. Identify all copies of the same pointer and clear the reference. + */ +static int release_reference(struct bpf_verifier_env *env, + struct bpf_call_arg_meta *meta) +{ + struct bpf_verifier_state *vstate = env->cur_state; + int i; + + for (i = 0; i <= vstate->curframe; i++) + release_reg_references(env, vstate->frame[i], meta->ptr_id); + + return release_reference_state(env, meta->ptr_id); +} + static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn, int *insn_idx) { struct bpf_verifier_state *state = env->cur_state; struct bpf_func_state *caller, *callee; - int i, subprog, target_insn; + int i, err, subprog, target_insn; if (state->curframe + 1 >= MAX_CALL_FRAMES) { verbose(env, "the call stack of %d frames is too deep\n", @@ -2366,11 +2601,18 @@ static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn, state->curframe + 1 /* frameno within this callchain */, subprog /* subprog number within this prog */); - /* copy r1 - r5 args that callee can access */ + /* Transfer references to the callee */ + err = transfer_reference_state(callee, caller); + if (err) + return err; + + /* copy r1 - r5 args that callee can access. The copy includes parent + * pointers, which connects us up to the liveness chain + */ for (i = BPF_REG_1; i <= BPF_REG_5; i++) callee->regs[i] = caller->regs[i]; - /* after the call regsiters r0 - r5 were scratched */ + /* after the call registers r0 - r5 were scratched */ for (i = 0; i < CALLER_SAVED_REGS; i++) { mark_reg_not_init(env, caller->regs, caller_saved[i]); check_reg_arg(env, caller_saved[i], DST_OP_NO_MARK); @@ -2396,6 +2638,7 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx) struct bpf_verifier_state *state = env->cur_state; struct bpf_func_state *caller, *callee; struct bpf_reg_state *r0; + int err; callee = state->frame[state->curframe]; r0 = &callee->regs[BPF_REG_0]; @@ -2415,6 +2658,11 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx) /* return to the caller whatever r0 had in the callee */ caller->regs[BPF_REG_0] = *r0; + /* Transfer references to the caller */ + err = transfer_reference_state(caller, callee); + if (err) + return err; + *insn_idx = callee->callsite + 1; if (env->log.level) { verbose(env, "returning from callee:\n"); @@ -2454,7 +2702,10 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta, if (func_id != BPF_FUNC_tail_call && func_id != BPF_FUNC_map_lookup_elem && func_id != BPF_FUNC_map_update_elem && - func_id != BPF_FUNC_map_delete_elem) + func_id != BPF_FUNC_map_delete_elem && + func_id != BPF_FUNC_map_push_elem && + func_id != BPF_FUNC_map_pop_elem && + func_id != BPF_FUNC_map_peek_elem) return 0; if (meta->map_ptr == NULL) { @@ -2471,6 +2722,18 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta, return 0; } +static int check_reference_leak(struct bpf_verifier_env *env) +{ + struct bpf_func_state *state = cur_func(env); + int i; + + for (i = 0; i < state->acquired_refs; i++) { + verbose(env, "Unreleased reference id=%d alloc_insn=%d\n", + state->refs[i].id, state->refs[i].insn_idx); + } + return state->acquired_refs ? -EINVAL : 0; +} + static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx) { const struct bpf_func_proto *fn = NULL; @@ -2549,6 +2812,18 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn return err; } + if (func_id == BPF_FUNC_tail_call) { + err = check_reference_leak(env); + if (err) { + verbose(env, "tail_call would lead to reference leak\n"); + return err; + } + } else if (is_release_function(func_id)) { + err = release_reference(env, &meta); + if (err) + return err; + } + regs = cur_regs(env); /* check that flags argument in get_local_storage(map, flags) is 0, @@ -2580,7 +2855,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL; /* There is no offset yet applied, variable or fixed */ mark_reg_known_zero(env, regs, BPF_REG_0); - regs[BPF_REG_0].off = 0; /* remember map_ptr, so that check_map_access() * can check 'value_size' boundary of memory access * to map element returned from bpf_map_lookup_elem() @@ -2592,6 +2866,13 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn } regs[BPF_REG_0].map_ptr = meta.map_ptr; regs[BPF_REG_0].id = ++env->id_gen; + } else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) { + int id = acquire_reference_state(env, insn_idx); + if (id < 0) + return id; + mark_reg_known_zero(env, regs, BPF_REG_0); + regs[BPF_REG_0].type = PTR_TO_SOCKET_OR_NULL; + regs[BPF_REG_0].id = id; } else { verbose(env, "unknown return type %d of func %s#%d\n", fn->ret_type, func_id_name(func_id), func_id); @@ -2722,20 +3003,20 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, return -EACCES; } - if (ptr_reg->type == PTR_TO_MAP_VALUE_OR_NULL) { - verbose(env, "R%d pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL prohibited, null-check it first\n", - dst); - return -EACCES; - } - if (ptr_reg->type == CONST_PTR_TO_MAP) { - verbose(env, "R%d pointer arithmetic on CONST_PTR_TO_MAP prohibited\n", - dst); + switch (ptr_reg->type) { + case PTR_TO_MAP_VALUE_OR_NULL: + verbose(env, "R%d pointer arithmetic on %s prohibited, null-check it first\n", + dst, reg_type_str[ptr_reg->type]); return -EACCES; - } - if (ptr_reg->type == PTR_TO_PACKET_END) { - verbose(env, "R%d pointer arithmetic on PTR_TO_PACKET_END prohibited\n", - dst); + case CONST_PTR_TO_MAP: + case PTR_TO_PACKET_END: + case PTR_TO_SOCKET: + case PTR_TO_SOCKET_OR_NULL: + verbose(env, "R%d pointer arithmetic on %s prohibited\n", + dst, reg_type_str[ptr_reg->type]); return -EACCES; + default: + break; } /* In case of 'scalar += pointer', dst_reg inherits pointer type and id. @@ -3455,10 +3736,9 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *vstate, for (j = 0; j <= vstate->curframe; j++) { state = vstate->frame[j]; - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) + bpf_for_each_spilled_reg(i, state, reg) { + if (!reg) continue; - reg = &state->stack[i].spilled_ptr; if (reg->type == type && reg->id == dst_reg->id) reg->range = max(reg->range, new_range); } @@ -3664,12 +3944,11 @@ static void reg_combine_min_max(struct bpf_reg_state *true_src, } } -static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id, - bool is_null) +static void mark_ptr_or_null_reg(struct bpf_func_state *state, + struct bpf_reg_state *reg, u32 id, + bool is_null) { - struct bpf_reg_state *reg = ®s[regno]; - - if (reg->type == PTR_TO_MAP_VALUE_OR_NULL && reg->id == id) { + if (reg_type_may_be_null(reg->type) && reg->id == id) { /* Old offset (both fixed and variable parts) should * have been known-zero, because we don't allow pointer * arithmetic on pointers that might be NULL. @@ -3682,40 +3961,49 @@ static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id, } if (is_null) { reg->type = SCALAR_VALUE; - } else if (reg->map_ptr->inner_map_meta) { - reg->type = CONST_PTR_TO_MAP; - reg->map_ptr = reg->map_ptr->inner_map_meta; - } else { - reg->type = PTR_TO_MAP_VALUE; + } else if (reg->type == PTR_TO_MAP_VALUE_OR_NULL) { + if (reg->map_ptr->inner_map_meta) { + reg->type = CONST_PTR_TO_MAP; + reg->map_ptr = reg->map_ptr->inner_map_meta; + } else { + reg->type = PTR_TO_MAP_VALUE; + } + } else if (reg->type == PTR_TO_SOCKET_OR_NULL) { + reg->type = PTR_TO_SOCKET; + } + if (is_null || !reg_is_refcounted(reg)) { + /* We don't need id from this point onwards anymore, + * thus we should better reset it, so that state + * pruning has chances to take effect. + */ + reg->id = 0; } - /* We don't need id from this point onwards anymore, thus we - * should better reset it, so that state pruning has chances - * to take effect. - */ - reg->id = 0; } } /* The logic is similar to find_good_pkt_pointers(), both could eventually * be folded together at some point. */ -static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno, - bool is_null) +static void mark_ptr_or_null_regs(struct bpf_verifier_state *vstate, u32 regno, + bool is_null) { struct bpf_func_state *state = vstate->frame[vstate->curframe]; - struct bpf_reg_state *regs = state->regs; + struct bpf_reg_state *reg, *regs = state->regs; u32 id = regs[regno].id; int i, j; + if (reg_is_refcounted_or_null(®s[regno]) && is_null) + __release_reference_state(state, id); + for (i = 0; i < MAX_BPF_REG; i++) - mark_map_reg(regs, i, id, is_null); + mark_ptr_or_null_reg(state, ®s[i], id, is_null); for (j = 0; j <= vstate->curframe; j++) { state = vstate->frame[j]; - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) + bpf_for_each_spilled_reg(i, state, reg) { + if (!reg) continue; - mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null); + mark_ptr_or_null_reg(state, reg, id, is_null); } } } @@ -3917,12 +4205,14 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, /* detect if R == 0 where R is returned from bpf_map_lookup_elem() */ if (BPF_SRC(insn->code) == BPF_K && insn->imm == 0 && (opcode == BPF_JEQ || opcode == BPF_JNE) && - dst_reg->type == PTR_TO_MAP_VALUE_OR_NULL) { - /* Mark all identical map registers in each branch as either + reg_type_may_be_null(dst_reg->type)) { + /* Mark all identical registers in each branch as either * safe or unknown depending R == 0 or R != 0 conditional. */ - mark_map_regs(this_branch, insn->dst_reg, opcode == BPF_JNE); - mark_map_regs(other_branch, insn->dst_reg, opcode == BPF_JEQ); + mark_ptr_or_null_regs(this_branch, insn->dst_reg, + opcode == BPF_JNE); + mark_ptr_or_null_regs(other_branch, insn->dst_reg, + opcode == BPF_JEQ); } else if (!try_match_pkt_pointers(insn, dst_reg, ®s[insn->src_reg], this_branch, other_branch) && is_pointer_value(env, insn->dst_reg)) { @@ -4045,6 +4335,16 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn) if (err) return err; + /* Disallow usage of BPF_LD_[ABS|IND] with reference tracking, as + * gen_ld_abs() may terminate the program at runtime, leading to + * reference leak. + */ + err = check_reference_leak(env); + if (err) { + verbose(env, "BPF_LD_[ABS|IND] cannot be mixed with socket references\n"); + return err; + } + if (regs[BPF_REG_6].type != PTR_TO_CTX) { verbose(env, "at the time of BPF_LD_ABS|IND R6 != pointer to skb\n"); @@ -4378,7 +4678,7 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur, /* explored state didn't use this */ return true; - equal = memcmp(rold, rcur, offsetof(struct bpf_reg_state, frameno)) == 0; + equal = memcmp(rold, rcur, offsetof(struct bpf_reg_state, parent)) == 0; if (rold->type == PTR_TO_STACK) /* two stack pointers are equal only if they're pointing to @@ -4459,6 +4759,9 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur, case PTR_TO_CTX: case CONST_PTR_TO_MAP: case PTR_TO_PACKET_END: + case PTR_TO_FLOW_KEYS: + case PTR_TO_SOCKET: + case PTR_TO_SOCKET_OR_NULL: /* Only valid matches are exact, which memcmp() above * would have accepted */ @@ -4534,6 +4837,14 @@ static bool stacksafe(struct bpf_func_state *old, return true; } +static bool refsafe(struct bpf_func_state *old, struct bpf_func_state *cur) +{ + if (old->acquired_refs != cur->acquired_refs) + return false; + return !memcmp(old->refs, cur->refs, + sizeof(*old->refs) * old->acquired_refs); +} + /* compare two verifier states * * all states stored in state_list are known to be valid, since @@ -4579,6 +4890,9 @@ static bool func_states_equal(struct bpf_func_state *old, if (!stacksafe(old, cur, idmap)) goto out_free; + + if (!refsafe(old, cur)) + goto out_free; ret = true; out_free: kfree(idmap); @@ -4611,7 +4925,7 @@ static bool states_equal(struct bpf_verifier_env *env, * equivalent state (jump target or such) we didn't arrive by the straight-line * code, so read marks in the state must propagate to the parent regardless * of the state's write marks. That's what 'parent == state->parent' comparison - * in mark_reg_read() and mark_stack_slot_read() is for. + * in mark_reg_read() is for. */ static int propagate_liveness(struct bpf_verifier_env *env, const struct bpf_verifier_state *vstate, @@ -4632,7 +4946,8 @@ static int propagate_liveness(struct bpf_verifier_env *env, if (vparent->frame[vparent->curframe]->regs[i].live & REG_LIVE_READ) continue; if (vstate->frame[vstate->curframe]->regs[i].live & REG_LIVE_READ) { - err = mark_reg_read(env, vstate, vparent, i); + err = mark_reg_read(env, &vstate->frame[vstate->curframe]->regs[i], + &vparent->frame[vstate->curframe]->regs[i]); if (err) return err; } @@ -4647,7 +4962,8 @@ static int propagate_liveness(struct bpf_verifier_env *env, if (parent->stack[i].spilled_ptr.live & REG_LIVE_READ) continue; if (state->stack[i].spilled_ptr.live & REG_LIVE_READ) - mark_stack_slot_read(env, vstate, vparent, i, frame); + mark_reg_read(env, &state->stack[i].spilled_ptr, + &parent->stack[i].spilled_ptr); } } return err; @@ -4657,7 +4973,7 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) { struct bpf_verifier_state_list *new_sl; struct bpf_verifier_state_list *sl; - struct bpf_verifier_state *cur = env->cur_state; + struct bpf_verifier_state *cur = env->cur_state, *new; int i, j, err; sl = env->explored_states[insn_idx]; @@ -4699,16 +5015,18 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) return -ENOMEM; /* add new state to the head of linked list */ - err = copy_verifier_state(&new_sl->state, cur); + new = &new_sl->state; + err = copy_verifier_state(new, cur); if (err) { - free_verifier_state(&new_sl->state, false); + free_verifier_state(new, false); kfree(new_sl); return err; } new_sl->next = env->explored_states[insn_idx]; env->explored_states[insn_idx] = new_sl; /* connect new state to parentage chain */ - cur->parent = &new_sl->state; + for (i = 0; i < BPF_REG_FP; i++) + cur_regs(env)[i].parent = &new->frame[new->curframe]->regs[i]; /* clear write marks in current state: the writes we did are not writes * our child did, so they don't screen off its reads from us. * (There are no read marks in current state, because reads always mark @@ -4721,13 +5039,48 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) /* all stack frames are accessible from callee, clear them all */ for (j = 0; j <= cur->curframe; j++) { struct bpf_func_state *frame = cur->frame[j]; + struct bpf_func_state *newframe = new->frame[j]; - for (i = 0; i < frame->allocated_stack / BPF_REG_SIZE; i++) + for (i = 0; i < frame->allocated_stack / BPF_REG_SIZE; i++) { frame->stack[i].spilled_ptr.live = REG_LIVE_NONE; + frame->stack[i].spilled_ptr.parent = + &newframe->stack[i].spilled_ptr; + } } return 0; } +/* Return true if it's OK to have the same insn return a different type. */ +static bool reg_type_mismatch_ok(enum bpf_reg_type type) +{ + switch (type) { + case PTR_TO_CTX: + case PTR_TO_SOCKET: + case PTR_TO_SOCKET_OR_NULL: + return false; + default: + return true; + } +} + +/* If an instruction was previously used with particular pointer types, then we + * need to be careful to avoid cases such as the below, where it may be ok + * for one branch accessing the pointer, but not ok for the other branch: + * + * R1 = sock_ptr + * goto X; + * ... + * R1 = some_other_valid_ptr; + * goto X; + * ... + * R2 = *(u32 *)(R1 + 0); + */ +static bool reg_type_mismatch(enum bpf_reg_type src, enum bpf_reg_type prev) +{ + return src != prev && (!reg_type_mismatch_ok(src) || + !reg_type_mismatch_ok(prev)); +} + static int do_check(struct bpf_verifier_env *env) { struct bpf_verifier_state *state; @@ -4742,7 +5095,6 @@ static int do_check(struct bpf_verifier_env *env) if (!state) return -ENOMEM; state->curframe = 0; - state->parent = NULL; state->frame[0] = kzalloc(sizeof(struct bpf_func_state), GFP_KERNEL); if (!state->frame[0]) { kfree(state); @@ -4822,6 +5174,7 @@ static int do_check(struct bpf_verifier_env *env) regs = cur_regs(env); env->insn_aux_data[insn_idx].seen = true; + if (class == BPF_ALU || class == BPF_ALU64) { err = check_alu_op(env, insn); if (err) @@ -4861,9 +5214,7 @@ static int do_check(struct bpf_verifier_env *env) */ *prev_src_type = src_reg_type; - } else if (src_reg_type != *prev_src_type && - (src_reg_type == PTR_TO_CTX || - *prev_src_type == PTR_TO_CTX)) { + } else if (reg_type_mismatch(src_reg_type, *prev_src_type)) { /* ABuser program is trying to use the same insn * dst_reg = *(u32*) (src_reg + off) * with different pointer types: @@ -4908,9 +5259,7 @@ static int do_check(struct bpf_verifier_env *env) if (*prev_dst_type == NOT_INIT) { *prev_dst_type = dst_reg_type; - } else if (dst_reg_type != *prev_dst_type && - (dst_reg_type == PTR_TO_CTX || - *prev_dst_type == PTR_TO_CTX)) { + } else if (reg_type_mismatch(dst_reg_type, *prev_dst_type)) { verbose(env, "same insn cannot be used with different pointers\n"); return -EINVAL; } @@ -4927,8 +5276,9 @@ static int do_check(struct bpf_verifier_env *env) return err; if (is_ctx_reg(env, insn->dst_reg)) { - verbose(env, "BPF_ST stores into R%d context is not allowed\n", - insn->dst_reg); + verbose(env, "BPF_ST stores into R%d %s is not allowed\n", + insn->dst_reg, + reg_type_str[reg_state(env, insn->dst_reg)->type]); return -EACCES; } @@ -4990,6 +5340,10 @@ static int do_check(struct bpf_verifier_env *env) continue; } + err = check_reference_leak(env); + if (err) + return err; + /* eBPF calling convetion is such that R0 is used * to return the value from eBPF program. * Make sure that it's readable at this time @@ -5103,6 +5457,12 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, return 0; } +static bool bpf_map_is_cgroup_storage(struct bpf_map *map) +{ + return (map->map_type == BPF_MAP_TYPE_CGROUP_STORAGE || + map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE); +} + /* look for pseudo eBPF instructions that access map FDs and * replace them with actual map pointers */ @@ -5193,10 +5553,9 @@ static int replace_map_fd_with_map_ptr(struct bpf_verifier_env *env) } env->used_maps[env->used_map_cnt++] = map; - if (map->map_type == BPF_MAP_TYPE_CGROUP_STORAGE && + if (bpf_map_is_cgroup_storage(map) && bpf_cgroup_storage_assign(env->prog, map)) { - verbose(env, - "only one cgroup storage is allowed\n"); + verbose(env, "only one cgroup storage of each type is allowed\n"); fdput(f); return -EBUSY; } @@ -5225,11 +5584,15 @@ next_insn: /* drop refcnt of maps used by the rejected program */ static void release_maps(struct bpf_verifier_env *env) { + enum bpf_cgroup_storage_type stype; int i; - if (env->prog->aux->cgroup_storage) + for_each_cgroup_storage_type(stype) { + if (!env->prog->aux->cgroup_storage[stype]) + continue; bpf_cgroup_storage_release(env->prog, - env->prog->aux->cgroup_storage); + env->prog->aux->cgroup_storage[stype]); + } for (i = 0; i < env->used_map_cnt; i++) bpf_map_put(env->used_maps[i]); @@ -5327,8 +5690,10 @@ static void sanitize_dead_code(struct bpf_verifier_env *env) } } -/* convert load instructions that access fields of 'struct __sk_buff' - * into sequence of instructions that access fields of 'struct sk_buff' +/* convert load instructions that access fields of a context type into a + * sequence of instructions that access fields of the underlying structure: + * struct __sk_buff -> struct sk_buff + * struct bpf_sock_ops -> struct sock */ static int convert_ctx_accesses(struct bpf_verifier_env *env) { @@ -5357,12 +5722,14 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) } } - if (!ops->convert_ctx_access || bpf_prog_is_dev_bound(env->prog->aux)) + if (bpf_prog_is_dev_bound(env->prog->aux)) return 0; insn = env->prog->insnsi + delta; for (i = 0; i < insn_cnt; i++, insn++) { + bpf_convert_ctx_access_t convert_ctx_access; + if (insn->code == (BPF_LDX | BPF_MEM | BPF_B) || insn->code == (BPF_LDX | BPF_MEM | BPF_H) || insn->code == (BPF_LDX | BPF_MEM | BPF_W) || @@ -5404,8 +5771,18 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) continue; } - if (env->insn_aux_data[i + delta].ptr_type != PTR_TO_CTX) + switch (env->insn_aux_data[i + delta].ptr_type) { + case PTR_TO_CTX: + if (!ops->convert_ctx_access) + continue; + convert_ctx_access = ops->convert_ctx_access; + break; + case PTR_TO_SOCKET: + convert_ctx_access = bpf_sock_convert_ctx_access; + break; + default: continue; + } ctx_field_size = env->insn_aux_data[i + delta].ctx_field_size; size = BPF_LDST_BYTES(insn); @@ -5437,8 +5814,8 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) } target_size = 0; - cnt = ops->convert_ctx_access(type, insn, insn_buf, env->prog, - &target_size); + cnt = convert_ctx_access(type, insn, insn_buf, env->prog, + &target_size); if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf) || (ctx_field_size && !target_size)) { verbose(env, "bpf verifier is misconfigured\n"); @@ -5629,10 +6006,10 @@ static int fixup_call_args(struct bpf_verifier_env *env) struct bpf_insn *insn = prog->insnsi; int i, depth; #endif - int err; + int err = 0; - err = 0; - if (env->prog->jit_requested) { + if (env->prog->jit_requested && + !bpf_prog_is_dev_bound(env->prog->aux)) { err = jit_subprogs(env); if (err == 0) return 0; @@ -5801,7 +6178,10 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) if (prog->jit_requested && BITS_PER_LONG == 64 && (insn->imm == BPF_FUNC_map_lookup_elem || insn->imm == BPF_FUNC_map_update_elem || - insn->imm == BPF_FUNC_map_delete_elem)) { + insn->imm == BPF_FUNC_map_delete_elem || + insn->imm == BPF_FUNC_map_push_elem || + insn->imm == BPF_FUNC_map_pop_elem || + insn->imm == BPF_FUNC_map_peek_elem)) { aux = &env->insn_aux_data[i + delta]; if (bpf_map_ptr_poisoned(aux)) goto patch_call_imm; @@ -5834,6 +6214,14 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) BUILD_BUG_ON(!__same_type(ops->map_update_elem, (int (*)(struct bpf_map *map, void *key, void *value, u64 flags))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_push_elem, + (int (*)(struct bpf_map *map, void *value, + u64 flags))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_pop_elem, + (int (*)(struct bpf_map *map, void *value))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_peek_elem, + (int (*)(struct bpf_map *map, void *value))NULL)); + switch (insn->imm) { case BPF_FUNC_map_lookup_elem: insn->imm = BPF_CAST_CALL(ops->map_lookup_elem) - @@ -5847,6 +6235,18 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) insn->imm = BPF_CAST_CALL(ops->map_delete_elem) - __bpf_call_base; continue; + case BPF_FUNC_map_push_elem: + insn->imm = BPF_CAST_CALL(ops->map_push_elem) - + __bpf_call_base; + continue; + case BPF_FUNC_map_pop_elem: + insn->imm = BPF_CAST_CALL(ops->map_pop_elem) - + __bpf_call_base; + continue; + case BPF_FUNC_map_peek_elem: + insn->imm = BPF_CAST_CALL(ops->map_peek_elem) - + __bpf_call_base; + continue; } goto patch_call_imm; @@ -5970,6 +6370,9 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) env->cur_state = NULL; } + if (ret == 0 && bpf_prog_is_dev_bound(env->prog->aux)) + ret = bpf_prog_offload_finalize(env); + skip_full_check: while (!pop_stack(env, NULL, NULL)); free_states(env); diff --git a/kernel/bpf/xskmap.c b/kernel/bpf/xskmap.c index 47147c9e184d..686d244e798d 100644 --- a/kernel/bpf/xskmap.c +++ b/kernel/bpf/xskmap.c @@ -154,7 +154,7 @@ void __xsk_map_flush(struct bpf_map *map) static void *xsk_map_lookup_elem(struct bpf_map *map, void *key) { - return NULL; + return ERR_PTR(-EOPNOTSUPP); } static int xsk_map_update_elem(struct bpf_map *map, void *key, void *value, diff --git a/kernel/umh.c b/kernel/umh.c index c449858946af..0baa672e023c 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -405,11 +405,19 @@ struct subprocess_info *call_usermodehelper_setup_file(struct file *file, void (*cleanup)(struct subprocess_info *info), void *data) { struct subprocess_info *sub_info; + struct umh_info *info = data; + const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper"; sub_info = kzalloc(sizeof(struct subprocess_info), GFP_KERNEL); if (!sub_info) return NULL; + sub_info->argv = argv_split(GFP_KERNEL, cmdline, NULL); + if (!sub_info->argv) { + kfree(sub_info); + return NULL; + } + INIT_WORK(&sub_info->work, call_usermodehelper_exec_work); sub_info->path = "none"; sub_info->file = file; @@ -458,10 +466,11 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new) return 0; } -static void umh_save_pid(struct subprocess_info *info) +static void umh_clean_and_save_pid(struct subprocess_info *info) { struct umh_info *umh_info = info->data; + argv_free(info->argv); umh_info->pid = info->pid; } @@ -471,6 +480,9 @@ static void umh_save_pid(struct subprocess_info *info) * @len: length of the blob * @info: information about usermode process (shouldn't be NULL) * + * If info->cmdline is set it will be used as command line for the + * user process, else "usermodehelper" is used. + * * Returns either negative error or zero which indicates success * in executing a blob of bytes as a usermode process. In such * case 'struct umh_info *info' is populated with two pipes @@ -500,7 +512,7 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info) err = -ENOMEM; sub_info = call_usermodehelper_setup_file(file, umh_pipe_setup, - umh_save_pid, info); + umh_clean_and_save_pid, info); if (!sub_info) goto out; |