diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-08-18 04:51:32 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-30 17:35:14 +0300 |
| commit | ffb453aba871d52ecb87dea0632dcff24a655294 (patch) | |
| tree | 9d2dd94daed0e8c99ab6d9c31508d86214fcdfe6 | |
| parent | d6b35c9a8d51032ed9890431da3ae39fe76c1ae3 (diff) | |
| download | linux-ffb453aba871d52ecb87dea0632dcff24a655294.tar.xz | |
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 1937deba0849..7b42ddca4dec 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1115,6 +1115,7 @@ 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. */ @@ -1214,7 +1215,7 @@ 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) @@ -1226,7 +1227,7 @@ 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 @@ -1280,7 +1281,7 @@ 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 9414dcb376d2..e5c3c37108e4 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -110,7 +110,7 @@ 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); } |