diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-08-18 01:51:32 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-30 16:27:23 +0200 |
| commit | 7d6cc69199527397e38264f1d69f45ea5454b563 (patch) | |
| tree | 7f23509b397de3a505e788331b70429e1d0de9af | |
| parent | d28ea7acfae761b622710d78091d56e7b3267087 (diff) | |
sock: annotate data-races around prot->memory_pressure
[ Upstream commit 76f33296d2e09f63118db78125c95ef56df438e9 ]
*prot->memory_pressure is read/writen locklessly, we need
to add proper annotations.
A recent commit added a new race, it is time to audit all accesses.
Fixes: 2d0c88e84e48 ("sock: Fix misuse of sk_under_memory_pressure()")
Fixes: 4d93df0abd50 ("[SCTP]: Rewrite of sctp buffer management code")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Abel Wu <wuyun.abel@bytedance.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Link: https://lore.kernel.org/r/20230818015132.2699348-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/net/sock.h | 7 | ||||
| -rw-r--r-- | net/sctp/socket.c | 2 |
2 files changed, 5 insertions, 4 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 61f5872aac24..f73ef7087a18 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1161,6 +1161,7 @@ struct proto { /* * Pressure flag: try to collapse. * Technical note: it is used by multiple contexts non atomically. + * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes. * All the __sk_mem_schedule() is of this nature: accounting * is strict, actions are advisory and have some latency. */ @@ -1277,7 +1278,7 @@ static inline bool sk_has_memory_pressure(const struct sock *sk) static inline bool sk_under_global_memory_pressure(const struct sock *sk) { return sk->sk_prot->memory_pressure && - !!*sk->sk_prot->memory_pressure; + !!READ_ONCE(*sk->sk_prot->memory_pressure); } static inline bool sk_under_memory_pressure(const struct sock *sk) @@ -1289,7 +1290,7 @@ static inline bool sk_under_memory_pressure(const struct sock *sk) mem_cgroup_under_socket_pressure(sk->sk_memcg)) return true; - return !!*sk->sk_prot->memory_pressure; + return !!READ_ONCE(*sk->sk_prot->memory_pressure); } static inline long @@ -1343,7 +1344,7 @@ proto_memory_pressure(struct proto *prot) { if (!prot->memory_pressure) return false; - return !!*prot->memory_pressure; + return !!READ_ONCE(*prot->memory_pressure); } diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 7cff1a031f76..431b9399a781 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -97,7 +97,7 @@ struct percpu_counter sctp_sockets_allocated; static void sctp_enter_memory_pressure(struct sock *sk) { - sctp_memory_pressure = 1; + WRITE_ONCE(sctp_memory_pressure, 1); } |