diff options
| -rw-r--r-- | kernel/bpf/verifier.c | 45 | ||||
| -rw-r--r-- | net/core/filter.c | 4 | ||||
| -rw-r--r-- | net/core/sock_map.c | 18 |
3 files changed, 55 insertions, 12 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 2b337e32aa94..70ad009577f8 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -429,11 +429,30 @@ static bool is_release_function(enum bpf_func_id func_id) return func_id == BPF_FUNC_sk_release; } -static bool is_acquire_function(enum bpf_func_id func_id) +static bool may_be_acquire_function(enum bpf_func_id func_id) { return func_id == BPF_FUNC_sk_lookup_tcp || func_id == BPF_FUNC_sk_lookup_udp || - func_id == BPF_FUNC_skc_lookup_tcp; + func_id == BPF_FUNC_skc_lookup_tcp || + func_id == BPF_FUNC_map_lookup_elem; +} + +static bool is_acquire_function(enum bpf_func_id func_id, + const struct bpf_map *map) +{ + enum bpf_map_type map_type = map ? map->map_type : BPF_MAP_TYPE_UNSPEC; + + if (func_id == BPF_FUNC_sk_lookup_tcp || + func_id == BPF_FUNC_sk_lookup_udp || + func_id == BPF_FUNC_skc_lookup_tcp) + return true; + + if (func_id == BPF_FUNC_map_lookup_elem && + (map_type == BPF_MAP_TYPE_SOCKMAP || + map_type == BPF_MAP_TYPE_SOCKHASH)) + return true; + + return false; } static bool is_ptr_cast_function(enum bpf_func_id func_id) @@ -3934,7 +3953,8 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, func_id != BPF_FUNC_sock_map_update && func_id != BPF_FUNC_map_delete_elem && func_id != BPF_FUNC_msg_redirect_map && - func_id != BPF_FUNC_sk_select_reuseport) + func_id != BPF_FUNC_sk_select_reuseport && + func_id != BPF_FUNC_map_lookup_elem) goto error; break; case BPF_MAP_TYPE_SOCKHASH: @@ -3942,7 +3962,8 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, func_id != BPF_FUNC_sock_hash_update && func_id != BPF_FUNC_map_delete_elem && func_id != BPF_FUNC_msg_redirect_hash && - func_id != BPF_FUNC_sk_select_reuseport) + func_id != BPF_FUNC_sk_select_reuseport && + func_id != BPF_FUNC_map_lookup_elem) goto error; break; case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: @@ -4112,7 +4133,7 @@ static bool check_refcount_ok(const struct bpf_func_proto *fn, int func_id) /* A reference acquiring function cannot acquire * another refcounted ptr. */ - if (is_acquire_function(func_id) && count) + if (may_be_acquire_function(func_id) && count) return false; /* We only support one arg being unreferenced at the moment, @@ -4623,7 +4644,7 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn if (is_ptr_cast_function(func_id)) { /* For release_reference() */ regs[BPF_REG_0].ref_obj_id = meta.ref_obj_id; - } else if (is_acquire_function(func_id)) { + } else if (is_acquire_function(func_id, meta.map_ptr)) { int id = acquire_reference_state(env, insn_idx); if (id < 0) @@ -6532,12 +6553,16 @@ static void mark_ptr_or_null_reg(struct bpf_func_state *state, if (is_null) { reg->type = SCALAR_VALUE; } else if (reg->type == PTR_TO_MAP_VALUE_OR_NULL) { - if (reg->map_ptr->inner_map_meta) { + const struct bpf_map *map = reg->map_ptr; + + if (map->inner_map_meta) { reg->type = CONST_PTR_TO_MAP; - reg->map_ptr = reg->map_ptr->inner_map_meta; - } else if (reg->map_ptr->map_type == - BPF_MAP_TYPE_XSKMAP) { + reg->map_ptr = map->inner_map_meta; + } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) { reg->type = PTR_TO_XDP_SOCK; + } else if (map->map_type == BPF_MAP_TYPE_SOCKMAP || + map->map_type == BPF_MAP_TYPE_SOCKHASH) { + reg->type = PTR_TO_SOCKET; } else { reg->type = PTR_TO_MAP_VALUE; } diff --git a/net/core/filter.c b/net/core/filter.c index da3b7a72c37c..70b32723e6be 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8712,6 +8712,10 @@ BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern, reuse = rcu_dereference(selected_sk->sk_reuseport_cb); if (!reuse) { + /* Lookup in sock_map can return TCP ESTABLISHED sockets. */ + if (sk_is_refcounted(selected_sk)) + sock_put(selected_sk); + /* reuseport_array has only sk with non NULL sk_reuseport_cb. * The only (!reuse) case here is - the sk has already been * unhashed (e.g. by close()), so treat it as -ENOENT. diff --git a/net/core/sock_map.c b/net/core/sock_map.c index b08dfae10f88..00a26cf2cfe9 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -343,7 +343,14 @@ static struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key) static void *sock_map_lookup(struct bpf_map *map, void *key) { - return __sock_map_lookup_elem(map, *(u32 *)key); + struct sock *sk; + + sk = __sock_map_lookup_elem(map, *(u32 *)key); + if (!sk || !sk_fullsock(sk)) + return NULL; + if (sk_is_refcounted(sk) && !refcount_inc_not_zero(&sk->sk_refcnt)) + return NULL; + return sk; } static void *sock_map_lookup_sys(struct bpf_map *map, void *key) @@ -1051,7 +1058,14 @@ static void *sock_hash_lookup_sys(struct bpf_map *map, void *key) static void *sock_hash_lookup(struct bpf_map *map, void *key) { - return __sock_hash_lookup_elem(map, key); + struct sock *sk; + + sk = __sock_hash_lookup_elem(map, key); + if (!sk || !sk_fullsock(sk)) + return NULL; + if (sk_is_refcounted(sk) && !refcount_inc_not_zero(&sk->sk_refcnt)) + return NULL; + return sk; } static void sock_hash_release_progs(struct bpf_map *map) |