This is a note to let you know that I've just added the patch titled
tcp/dccp: Fix a data-race around sysctl_tcp_fwmark_accept.
to the 5.18-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-dccp-fix-a-data-race-around-sysctl_tcp_fwmark_ac.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e7395facd548e0afe40b3a3a5757c5a773537cd2
Author: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Date: Wed Jul 13 13:51:58 2022 -0700
tcp/dccp: Fix a data-race around sysctl_tcp_fwmark_accept.
[ Upstream commit 1a0008f9df59451d0a17806c1ee1a19857032fa8 ]
While reading sysctl_tcp_fwmark_accept, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.
Fixes: 84f39b08d786 ("net: support marking accepting TCP sockets")
Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 2f6b715acc15..d3cf5871289b 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -107,7 +107,8 @@ static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
{
- if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
+ if (!sk->sk_mark &&
+ READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept))
return skb->mark;
return sk->sk_mark;
