From: Kuniyuki Iwashima kuniyu@amazon.com
[ Upstream commit 92c0aa4175474483d6cf373314343d4e624e882a ]
While reading sysctl_tcp_probe_threshold, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader.
Fixes: 6b58e0a5f32d ("ipv4: Use binary search to choose tcp PMTU probe_size") Signed-off-by: Kuniyuki Iwashima kuniyu@amazon.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/tcp_output.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index e0009cd69da7..5b6d935a028c 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2005,7 +2005,7 @@ static int tcp_mtu_probe(struct sock *sk) * probing process by not resetting search range to its orignal. */ if (probe_size > tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_high) || - interval < net->ipv4.sysctl_tcp_probe_threshold) { + interval < READ_ONCE(net->ipv4.sysctl_tcp_probe_threshold)) { /* Check whether enough time has elaplased for * another round of probing. */