Commit 01788ca1 authored by Jason Xing's avatar Jason Xing Committed by Geliang Tang
Browse files

mptcp: annotate a data-race around sysctl_tcp_wmem[0] 

mainline inclusion
from mainline-v6.9-rc1
commit 9eb430d40e449640122b0b33ace1f33e793ecc5f
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I9VYQ9
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=9eb430d40e449640122b0b33ace1f33e793ecc5f



--------------------------------

It's possible that writer and the reader can manipulate the same
sysctl knob concurrently. Using READ_ONCE() to prevent reading
an old value.

Signed-off-by: default avatarJason Xing <kernelxing@tencent.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarMat Martineau <martineau@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Reviewed-by: default avatarJackie Liu <liuyun01@kylinos.cn>
Signed-off-by: default avatarGeliang Tang <tanggeliang@kylinos.cn>
parent fc1a65ff

net/mptcp/protocol.h

+1 −1
Original line number Diff line number Diff line
@@ -855,7 +855,7 @@ static inline void __mptcp_sync_sndbuf(struct sock *sk) 
	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)

		return;



	new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0];

	new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]);

	mptcp_for_each_subflow(mptcp_sk(sk), subflow) {

		ssk_sndbuf =  READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf);