This is a note to let you know that I've just added the patch titled
tcp: annotate data-races around icsk->icsk_user_timeout
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tcp-annotate-data-races-around-icsk-icsk_user_timeou.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 65a31d1209b2ad2cee321305e50cc53cc92031e7
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Wed Jul 19 21:28:56 2023 +0000
tcp: annotate data-races around icsk->icsk_user_timeout
[ Upstream commit 26023e91e12c68669db416b97234328a03d8e499 ]
This field can be read locklessly from do_tcp_getsockopt()
Fixes: dca43c75e7e5 ("tcp: Add TCP_USER_TIMEOUT socket option.")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230719212857.3943972-11-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 4556ba6e7d74d..c9b955d9d7ace 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3409,7 +3409,7 @@ EXPORT_SYMBOL(tcp_sock_set_syncnt);
void tcp_sock_set_user_timeout(struct sock *sk, u32 val)
{
lock_sock(sk);
- inet_csk(sk)->icsk_user_timeout = val;
+ WRITE_ONCE(inet_csk(sk)->icsk_user_timeout, val);
release_sock(sk);
}
EXPORT_SYMBOL(tcp_sock_set_user_timeout);
@@ -3729,7 +3729,7 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname,
if (val < 0)
err = -EINVAL;
else
- icsk->icsk_user_timeout = val;
+ WRITE_ONCE(icsk->icsk_user_timeout, val);
break;
case TCP_FASTOPEN:
@@ -4250,7 +4250,7 @@ int do_tcp_getsockopt(struct sock *sk, int level,
break;
case TCP_USER_TIMEOUT:
- val = icsk->icsk_user_timeout;
+ val = READ_ONCE(icsk->icsk_user_timeout);
break;
case TCP_FASTOPEN:
