diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/bpf-cgroup.h | 2 | ||||
-rw-r--r-- | include/linux/bpf.h | 41 | ||||
-rw-r--r-- | include/linux/filter.h | 37 | ||||
-rw-r--r-- | include/linux/inet_diag.h | 27 | ||||
-rw-r--r-- | include/linux/kernel.h | 7 | ||||
-rw-r--r-- | include/linux/netlink.h | 4 | ||||
-rw-r--r-- | include/linux/preempt.h | 30 | ||||
-rw-r--r-- | include/net/bpf_sk_storage.h | 27 | ||||
-rw-r--r-- | include/uapi/linux/bpf.h | 2 | ||||
-rw-r--r-- | include/uapi/linux/inet_diag.h | 5 | ||||
-rw-r--r-- | include/uapi/linux/sock_diag.h | 26 |
11 files changed, 179 insertions, 29 deletions
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index a11d5b7dbbf3..a7cd5c7a2509 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -36,7 +36,7 @@ struct bpf_cgroup_storage_map; struct bpf_storage_buffer { struct rcu_head rcu; - char data[0]; + char data[]; }; struct bpf_cgroup_storage { diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 49b1a70e12c8..6015a4daf118 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -859,7 +859,7 @@ struct bpf_prog_array_item { struct bpf_prog_array { struct rcu_head rcu; - struct bpf_prog_array_item items[0]; + struct bpf_prog_array_item items[]; }; struct bpf_prog_array *bpf_prog_array_alloc(u32 prog_cnt, gfp_t flags); @@ -885,7 +885,7 @@ int bpf_prog_array_copy(struct bpf_prog_array *old_array, struct bpf_prog *_prog; \ struct bpf_prog_array *_array; \ u32 _ret = 1; \ - preempt_disable(); \ + migrate_disable(); \ rcu_read_lock(); \ _array = rcu_dereference(array); \ if (unlikely(check_non_null && !_array))\ @@ -898,7 +898,7 @@ int bpf_prog_array_copy(struct bpf_prog_array *old_array, } \ _out: \ rcu_read_unlock(); \ - preempt_enable(); \ + migrate_enable(); \ _ret; \ }) @@ -932,7 +932,7 @@ _out: \ u32 ret; \ u32 _ret = 1; \ u32 _cn = 0; \ - preempt_disable(); \ + migrate_disable(); \ rcu_read_lock(); \ _array = rcu_dereference(array); \ _item = &_array->items[0]; \ @@ -944,7 +944,7 @@ _out: \ _item++; \ } \ rcu_read_unlock(); \ - preempt_enable(); \ + migrate_enable(); \ if (_ret) \ _ret = (_cn ? NET_XMIT_CN : NET_XMIT_SUCCESS); \ else \ @@ -961,6 +961,36 @@ _out: \ #ifdef CONFIG_BPF_SYSCALL DECLARE_PER_CPU(int, bpf_prog_active); +/* + * Block execution of BPF programs attached to instrumentation (perf, + * kprobes, tracepoints) to prevent deadlocks on map operations as any of + * these events can happen inside a region which holds a map bucket lock + * and can deadlock on it. + * + * Use the preemption safe inc/dec variants on RT because migrate disable + * is preemptible on RT and preemption in the middle of the RMW operation + * might lead to inconsistent state. Use the raw variants for non RT + * kernels as migrate_disable() maps to preempt_disable() so the slightly + * more expensive save operation can be avoided. + */ +static inline void bpf_disable_instrumentation(void) +{ + migrate_disable(); + if (IS_ENABLED(CONFIG_PREEMPT_RT)) + this_cpu_inc(bpf_prog_active); + else + __this_cpu_inc(bpf_prog_active); +} + +static inline void bpf_enable_instrumentation(void) +{ + if (IS_ENABLED(CONFIG_PREEMPT_RT)) + this_cpu_dec(bpf_prog_active); + else + __this_cpu_dec(bpf_prog_active); + migrate_enable(); +} + extern const struct file_operations bpf_map_fops; extern const struct file_operations bpf_prog_fops; @@ -993,6 +1023,7 @@ void __bpf_free_used_maps(struct bpf_prog_aux *aux, void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock); void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock); +struct bpf_map *bpf_map_get(u32 ufd); struct bpf_map *bpf_map_get_with_uref(u32 ufd); struct bpf_map *__bpf_map_get(struct fd f); void bpf_map_inc(struct bpf_map *map); diff --git a/include/linux/filter.h b/include/linux/filter.h index f349e2c0884c..43b5e455d2f5 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -561,7 +561,7 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); #define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \ u32 ret; \ - cant_sleep(); \ + cant_migrate(); \ if (static_branch_unlikely(&bpf_stats_enabled_key)) { \ struct bpf_prog_stats *stats; \ u64 start = sched_clock(); \ @@ -576,8 +576,30 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); } \ ret; }) -#define BPF_PROG_RUN(prog, ctx) __BPF_PROG_RUN(prog, ctx, \ - bpf_dispatcher_nopfunc) +#define BPF_PROG_RUN(prog, ctx) \ + __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nopfunc) + +/* + * Use in preemptible and therefore migratable context to make sure that + * the execution of the BPF program runs on one CPU. + * + * This uses migrate_disable/enable() explicitly to document that the + * invocation of a BPF program does not require reentrancy protection + * against a BPF program which is invoked from a preempting task. + * + * For non RT enabled kernels migrate_disable/enable() maps to + * preempt_disable/enable(), i.e. it disables also preemption. + */ +static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog, + const void *ctx) +{ + u32 ret; + + migrate_disable(); + ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nopfunc); + migrate_enable(); + return ret; +} #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN @@ -655,6 +677,7 @@ static inline u8 *bpf_skb_cb(struct sk_buff *skb) return qdisc_skb_cb(skb)->data; } +/* Must be invoked with migration disabled */ static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog, struct sk_buff *skb) { @@ -680,9 +703,9 @@ static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, { u32 res; - preempt_disable(); + migrate_disable(); res = __bpf_prog_run_save_cb(prog, skb); - preempt_enable(); + migrate_enable(); return res; } @@ -695,9 +718,7 @@ static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, if (unlikely(prog->cb_access)) memset(cb_data, 0, BPF_SKB_CB_LEN); - preempt_disable(); - res = BPF_PROG_RUN(prog, skb); - preempt_enable(); + res = bpf_prog_run_pin_on_cpu(prog, skb); return res; } diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h index 39faaaf843e1..e4ba25d63913 100644 --- a/include/linux/inet_diag.h +++ b/include/linux/inet_diag.h @@ -15,11 +15,9 @@ struct netlink_callback; struct inet_diag_handler { void (*dump)(struct sk_buff *skb, struct netlink_callback *cb, - const struct inet_diag_req_v2 *r, - struct nlattr *bc); + const struct inet_diag_req_v2 *r); - int (*dump_one)(struct sk_buff *in_skb, - const struct nlmsghdr *nlh, + int (*dump_one)(struct netlink_callback *cb, const struct inet_diag_req_v2 *req); void (*idiag_get_info)(struct sock *sk, @@ -40,18 +38,25 @@ struct inet_diag_handler { __u16 idiag_info_size; }; +struct bpf_sk_storage_diag; +struct inet_diag_dump_data { + struct nlattr *req_nlas[__INET_DIAG_REQ_MAX]; +#define inet_diag_nla_bc req_nlas[INET_DIAG_REQ_BYTECODE] +#define inet_diag_nla_bpf_stgs req_nlas[INET_DIAG_REQ_SK_BPF_STORAGES] + + struct bpf_sk_storage_diag *bpf_stg_diag; +}; + struct inet_connection_sock; int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, - struct sk_buff *skb, const struct inet_diag_req_v2 *req, - struct user_namespace *user_ns, - u32 pid, u32 seq, u16 nlmsg_flags, - const struct nlmsghdr *unlh, bool net_admin); + struct sk_buff *skb, struct netlink_callback *cb, + const struct inet_diag_req_v2 *req, + u16 nlmsg_flags, bool net_admin); void inet_diag_dump_icsk(struct inet_hashinfo *h, struct sk_buff *skb, struct netlink_callback *cb, - const struct inet_diag_req_v2 *r, - struct nlattr *bc); + const struct inet_diag_req_v2 *r); int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo, - struct sk_buff *in_skb, const struct nlmsghdr *nlh, + struct netlink_callback *cb, const struct inet_diag_req_v2 *req); struct sock *inet_diag_find_one_icsk(struct net *net, diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 0d9db2a14f44..9b7a8d74a9d6 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -257,6 +257,13 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset); #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) +#ifndef CONFIG_PREEMPT_RT +# define cant_migrate() cant_sleep() +#else + /* Placeholder for now */ +# define cant_migrate() do { } while (0) +#endif + /** * abs - return absolute value of an argument * @x: the value. If it is unsigned type, it is converted to signed type first. diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 205fa7b1f07a..788969ccbbde 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -188,10 +188,10 @@ struct netlink_callback { struct module *module; struct netlink_ext_ack *extack; u16 family; - u16 min_dump_alloc; - bool strict_check; u16 answer_flags; + u32 min_dump_alloc; unsigned int prev_seq, seq; + bool strict_check; union { u8 ctx[48]; diff --git a/include/linux/preempt.h b/include/linux/preempt.h index bbb68dba37cc..bc3f1aecaa19 100644 --- a/include/linux/preempt.h +++ b/include/linux/preempt.h @@ -322,4 +322,34 @@ static inline void preempt_notifier_init(struct preempt_notifier *notifier, #endif +/** + * migrate_disable - Prevent migration of the current task + * + * Maps to preempt_disable() which also disables preemption. Use + * migrate_disable() to annotate that the intent is to prevent migration, + * but not necessarily preemption. + * + * Can be invoked nested like preempt_disable() and needs the corresponding + * number of migrate_enable() invocations. + */ +static __always_inline void migrate_disable(void) +{ + preempt_disable(); +} + +/** + * migrate_enable - Allow migration of the current task + * + * Counterpart to migrate_disable(). + * + * As migrate_disable() can be invoked nested, only the outermost invocation + * reenables migration. + * + * Currently mapped to preempt_enable(). + */ +static __always_inline void migrate_enable(void) +{ + preempt_enable(); +} + #endif /* __LINUX_PREEMPT_H */ diff --git a/include/net/bpf_sk_storage.h b/include/net/bpf_sk_storage.h index 8e4f831d2e52..5036c94c0503 100644 --- a/include/net/bpf_sk_storage.h +++ b/include/net/bpf_sk_storage.h @@ -10,14 +10,41 @@ void bpf_sk_storage_free(struct sock *sk); extern const struct bpf_func_proto bpf_sk_storage_get_proto; extern const struct bpf_func_proto bpf_sk_storage_delete_proto; +struct bpf_sk_storage_diag; +struct sk_buff; +struct nlattr; +struct sock; + #ifdef CONFIG_BPF_SYSCALL int bpf_sk_storage_clone(const struct sock *sk, struct sock *newsk); +struct bpf_sk_storage_diag * +bpf_sk_storage_diag_alloc(const struct nlattr *nla_stgs); +void bpf_sk_storage_diag_free(struct bpf_sk_storage_diag *diag); +int bpf_sk_storage_diag_put(struct bpf_sk_storage_diag *diag, + struct sock *sk, struct sk_buff *skb, + int stg_array_type, + unsigned int *res_diag_size); #else static inline int bpf_sk_storage_clone(const struct sock *sk, struct sock *newsk) { return 0; } +static inline struct bpf_sk_storage_diag * +bpf_sk_storage_diag_alloc(const struct nlattr *nla) +{ + return NULL; +} +static inline void bpf_sk_storage_diag_free(struct bpf_sk_storage_diag *diag) +{ +} +static inline int bpf_sk_storage_diag_put(struct bpf_sk_storage_diag *diag, + struct sock *sk, struct sk_buff *skb, + int stg_array_type, + unsigned int *res_diag_size) +{ + return 0; +} #endif #endif /* _BPF_SK_STORAGE_H */ diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 906e9f2752db..8e98ced0963b 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -73,7 +73,7 @@ struct bpf_insn { /* Key of an a BPF_MAP_TYPE_LPM_TRIE entry */ struct bpf_lpm_trie_key { __u32 prefixlen; /* up to 32 for AF_INET, 128 for AF_INET6 */ - __u8 data[0]; /* Arbitrary size */ + __u8 data[]; /* Arbitrary size */ }; struct bpf_cgroup_storage_key { diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index a1ff345b3f33..75dffd78363a 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -64,9 +64,11 @@ struct inet_diag_req_raw { enum { INET_DIAG_REQ_NONE, INET_DIAG_REQ_BYTECODE, + INET_DIAG_REQ_SK_BPF_STORAGES, + __INET_DIAG_REQ_MAX, }; -#define INET_DIAG_REQ_MAX INET_DIAG_REQ_BYTECODE +#define INET_DIAG_REQ_MAX (__INET_DIAG_REQ_MAX - 1) /* Bytecode is sequence of 4 byte commands followed by variable arguments. * All the commands identified by "code" are conditional jumps forward: @@ -154,6 +156,7 @@ enum { INET_DIAG_CLASS_ID, /* request as INET_DIAG_TCLASS */ INET_DIAG_MD5SIG, INET_DIAG_ULP_INFO, + INET_DIAG_SK_BPF_STORAGES, __INET_DIAG_MAX, }; diff --git a/include/uapi/linux/sock_diag.h b/include/uapi/linux/sock_diag.h index e5925009a652..5f74a5f6091d 100644 --- a/include/uapi/linux/sock_diag.h +++ b/include/uapi/linux/sock_diag.h @@ -36,4 +36,30 @@ enum sknetlink_groups { }; #define SKNLGRP_MAX (__SKNLGRP_MAX - 1) +enum { + SK_DIAG_BPF_STORAGE_REQ_NONE, + SK_DIAG_BPF_STORAGE_REQ_MAP_FD, + __SK_DIAG_BPF_STORAGE_REQ_MAX, +}; + +#define SK_DIAG_BPF_STORAGE_REQ_MAX (__SK_DIAG_BPF_STORAGE_REQ_MAX - 1) + +enum { + SK_DIAG_BPF_STORAGE_REP_NONE, + SK_DIAG_BPF_STORAGE, + __SK_DIAG_BPF_STORAGE_REP_MAX, +}; + +#define SK_DIAB_BPF_STORAGE_REP_MAX (__SK_DIAG_BPF_STORAGE_REP_MAX - 1) + +enum { + SK_DIAG_BPF_STORAGE_NONE, + SK_DIAG_BPF_STORAGE_PAD, + SK_DIAG_BPF_STORAGE_MAP_ID, + SK_DIAG_BPF_STORAGE_MAP_VALUE, + __SK_DIAG_BPF_STORAGE_MAX, +}; + +#define SK_DIAG_BPF_STORAGE_MAX (__SK_DIAG_BPF_STORAGE_MAX - 1) + #endif /* _UAPI__SOCK_DIAG_H__ */ |