From d9de17ff719d329b86ffe21b0a963f3c419c97e0 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 18 Jul 2022 10:26:51 -0700 Subject: [PATCH] tcp: Fix a data-race around sysctl_tcp_rfc1337. [ Upstream commit b5475f6aa3a30ecb2b8f7b0a6bcefd2e4ecd5c09 ] While reading sysctl_tcp_rfc1337, 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/tcp_minisocks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 9b038cb0a43d2..324f43fadb37a 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -180,7 +180,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, * Oh well... nobody has a sufficient solution to this * protocol bug yet. */ - if (twsk_net(tw)->ipv4.sysctl_tcp_rfc1337 == 0) { + if (!READ_ONCE(twsk_net(tw)->ipv4.sysctl_tcp_rfc1337)) { kill: inet_twsk_deschedule_put(tw); return TCP_TW_SUCCESS; -- 2.39.5