From 4ecabd55c90469629460f035f4bf4c8ae3d2743b Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Thu, 6 Jun 2019 13:30:12 -0700 Subject: bpf: allow CGROUP_SKB programs to use bpf_skb_cgroup_id() helper Currently bpf_skb_cgroup_id() is not supported for CGROUP_SKB programs. An attempt to load such a program generates an error like this: libbpf: 0: (b7) r6 = 0 ... 9: (85) call bpf_skb_cgroup_id#79 unknown func bpf_skb_cgroup_id#79 There are no particular reasons for denying it, and we have some use cases where it might be useful. So let's add it to the list of allowed helpers. Signed-off-by: Roman Gushchin Cc: Yonghong Song Cc: Alexei Starovoitov Cc: Daniel Borkmann Acked-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann --- net/core/filter.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/core') diff --git a/net/core/filter.c b/net/core/filter.c index 55bfc941d17a..f2777dc0b624 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -5919,6 +5919,10 @@ cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_sk_storage_get_proto; case BPF_FUNC_sk_storage_delete: return &bpf_sk_storage_delete_proto; +#ifdef CONFIG_SOCK_CGROUP_DATA + case BPF_FUNC_skb_cgroup_id: + return &bpf_skb_cgroup_id_proto; +#endif #ifdef CONFIG_INET case BPF_FUNC_tcp_sock: return &bpf_tcp_sock_proto; -- cgit v1.2.3 From fada7fdc83c0bf8755956bff707c42b609223301 Mon Sep 17 00:00:00 2001 From: Jonathan Lemon Date: Thu, 6 Jun 2019 13:59:40 -0700 Subject: bpf: Allow bpf_map_lookup_elem() on an xskmap Currently, the AF_XDP code uses a separate map in order to determine if an xsk is bound to a queue. Instead of doing this, have bpf_map_lookup_elem() return a xdp_sock. Rearrange some xdp_sock members to eliminate structure holes. Remove selftest - will be added back in later patch. Signed-off-by: Jonathan Lemon Acked-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov --- net/core/filter.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) (limited to 'net/core') diff --git a/net/core/filter.c b/net/core/filter.c index f2777dc0b624..a5e4ac7fcbe5 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -5680,6 +5680,46 @@ BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb) return INET_ECN_set_ce(skb); } +bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type, + struct bpf_insn_access_aux *info) +{ + if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id)) + return false; + + if (off % size != 0) + return false; + + switch (off) { + default: + return size == sizeof(__u32); + } +} + +u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type, + const struct bpf_insn *si, + struct bpf_insn *insn_buf, + struct bpf_prog *prog, u32 *target_size) +{ + struct bpf_insn *insn = insn_buf; + +#define BPF_XDP_SOCK_GET(FIELD) \ + do { \ + BUILD_BUG_ON(FIELD_SIZEOF(struct xdp_sock, FIELD) > \ + FIELD_SIZEOF(struct bpf_xdp_sock, FIELD)); \ + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\ + si->dst_reg, si->src_reg, \ + offsetof(struct xdp_sock, FIELD)); \ + } while (0) + + switch (si->off) { + case offsetof(struct bpf_xdp_sock, queue_id): + BPF_XDP_SOCK_GET(queue_id); + break; + } + + return insn - insn_buf; +} + static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = { .func = bpf_skb_ecn_set_ce, .gpl_only = false, -- cgit v1.2.3 From 99f3a064bc2e4bd5fe50218646c5be342f2ad18c Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Thu, 13 Jun 2019 15:00:01 -0700 Subject: bpf: net: Add SO_DETACH_REUSEPORT_BPF There is SO_ATTACH_REUSEPORT_[CE]BPF but there is no DETACH. This patch adds SO_DETACH_REUSEPORT_BPF sockopt. The same sockopt can be used to undo both SO_ATTACH_REUSEPORT_[CE]BPF. reseport_detach_prog() is added and it is mostly a mirror of the existing reuseport_attach_prog(). The differences are, it does not call reuseport_alloc() and returns -ENOENT when there is no old prog. Cc: Craig Gallek Signed-off-by: Martin KaFai Lau Reviewed-by: Stanislav Fomichev Signed-off-by: Daniel Borkmann --- net/core/sock.c | 4 ++++ net/core/sock_reuseport.c | 24 ++++++++++++++++++++++++ 2 files changed, 28 insertions(+) (limited to 'net/core') diff --git a/net/core/sock.c b/net/core/sock.c index 75b1c950b49f..06be30737b69 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1045,6 +1045,10 @@ set_rcvbuf: } break; + case SO_DETACH_REUSEPORT_BPF: + ret = reuseport_detach_prog(sk); + break; + case SO_DETACH_FILTER: ret = sk_detach_filter(sk); break; diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c index dc4aefdf2a08..9408f9264d05 100644 --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -332,3 +332,27 @@ int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog) return 0; } EXPORT_SYMBOL(reuseport_attach_prog); + +int reuseport_detach_prog(struct sock *sk) +{ + struct sock_reuseport *reuse; + struct bpf_prog *old_prog; + + if (!rcu_access_pointer(sk->sk_reuseport_cb)) + return sk->sk_reuseport ? -ENOENT : -EINVAL; + + old_prog = NULL; + spin_lock_bh(&reuseport_lock); + reuse = rcu_dereference_protected(sk->sk_reuseport_cb, + lockdep_is_held(&reuseport_lock)); + rcu_swap_protected(reuse->prog, old_prog, + lockdep_is_held(&reuseport_lock)); + spin_unlock_bh(&reuseport_lock); + + if (!old_prog) + return -ENOENT; + + sk_reuseport_prog_free(old_prog); + return 0; +} +EXPORT_SYMBOL(reuseport_detach_prog); -- cgit v1.2.3 From fb85c4a730af221339c1dde1a434b73da0dfc3ed Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Wed, 12 Jun 2019 10:30:37 -0700 Subject: bpf: export bpf_sock for BPF_PROG_TYPE_CGROUP_SOCK_ADDR prog type And let it use bpf_sk_storage_{get,delete} helpers to access socket storage. Kernel context (struct bpf_sock_addr_kern) already has sk member, so I just expose it to the BPF hooks. Using PTR_TO_SOCKET instead of PTR_TO_SOCK_COMMON should be safe because the hook is called on bind/connect. Cc: Martin Lau Signed-off-by: Stanislav Fomichev Signed-off-by: Daniel Borkmann --- net/core/filter.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'net/core') diff --git a/net/core/filter.c b/net/core/filter.c index a5e4ac7fcbe5..37c4a2fd559b 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -5922,6 +5922,10 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_skc_lookup_tcp: return &bpf_sock_addr_skc_lookup_tcp_proto; #endif /* CONFIG_INET */ + case BPF_FUNC_sk_storage_get: + return &bpf_sk_storage_get_proto; + case BPF_FUNC_sk_storage_delete: + return &bpf_sk_storage_delete_proto; default: return bpf_base_func_proto(func_id); } @@ -6828,6 +6832,13 @@ static bool sock_addr_is_valid_access(int off, int size, if (size != size_default) return false; break; + case offsetof(struct bpf_sock_addr, sk): + if (type != BPF_READ) + return false; + if (size != sizeof(__u64)) + return false; + info->reg_type = PTR_TO_SOCKET; + break; default: if (type == BPF_READ) { if (size != size_default) @@ -7778,6 +7789,11 @@ static u32 sock_addr_convert_ctx_access(enum bpf_access_type type, struct bpf_sock_addr_kern, struct in6_addr, t_ctx, s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg); break; + case offsetof(struct bpf_sock_addr, sk): + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk), + si->dst_reg, si->src_reg, + offsetof(struct bpf_sock_addr_kern, sk)); + break; } return insn - insn_buf; -- cgit v1.2.3 From 1314ef561102e534e14cb1d37f89f5c1df0b2ea7 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Wed, 12 Jun 2019 10:30:38 -0700 Subject: bpf: export bpf_sock for BPF_PROG_TYPE_SOCK_OPS prog type And let it use bpf_sk_storage_{get,delete} helpers to access socket storage. Kernel context (struct bpf_sock_ops_kern) already has sk member, so I just expose it to the BPF hooks. I use PTR_TO_SOCKET_OR_NULL and return NULL in !is_fullsock case. I also export bpf_tcp_sock to make it possible to access tcp socket stats. Cc: Martin Lau Signed-off-by: Stanislav Fomichev Signed-off-by: Daniel Borkmann --- net/core/filter.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'net/core') diff --git a/net/core/filter.c b/net/core/filter.c index 37c4a2fd559b..8c18f2781afa 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -6147,6 +6147,14 @@ sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_local_storage_proto; case BPF_FUNC_perf_event_output: return &bpf_sockopt_event_output_proto; + case BPF_FUNC_sk_storage_get: + return &bpf_sk_storage_get_proto; + case BPF_FUNC_sk_storage_delete: + return &bpf_sk_storage_delete_proto; +#ifdef CONFIG_INET + case BPF_FUNC_tcp_sock: + return &bpf_tcp_sock_proto; +#endif /* CONFIG_INET */ default: return bpf_base_func_proto(func_id); } @@ -6882,6 +6890,11 @@ static bool sock_ops_is_valid_access(int off, int size, if (size != sizeof(__u64)) return false; break; + case offsetof(struct bpf_sock_ops, sk): + if (size != sizeof(__u64)) + return false; + info->reg_type = PTR_TO_SOCKET_OR_NULL; + break; default: if (size != size_default) return false; @@ -8053,6 +8066,19 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash, struct sock, type); break; + case offsetof(struct bpf_sock_ops, sk): + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( + struct bpf_sock_ops_kern, + is_fullsock), + si->dst_reg, si->src_reg, + offsetof(struct bpf_sock_ops_kern, + is_fullsock)); + *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1); + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( + struct bpf_sock_ops_kern, sk), + si->dst_reg, si->src_reg, + offsetof(struct bpf_sock_ops_kern, sk)); + break; } return insn - insn_buf; } -- cgit v1.2.3