From: Kuniyuki Iwashima <kuniyu@amazon.com> stable inclusion from stable-v5.10.135 commit 3cddb7a7a5d5ceaf02354b127e64985d09f83e9a category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ZWFM Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 02ca527ac5581cf56749db9fd03d854e842253dd upstream. While reading sysctl_tcp_app_win, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- net/ipv4/tcp_input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 6331f9afdc33..fc2cec027f31 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -503,7 +503,7 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb) */ static void tcp_init_buffer_space(struct sock *sk) { - int tcp_app_win = sock_net(sk)->ipv4.sysctl_tcp_app_win; + int tcp_app_win = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_app_win); struct tcp_sock *tp = tcp_sk(sk); int maxwin; -- 2.20.1