From: Kuniyuki Iwashima kuniyu@amazon.com
[ Upstream commit 47e6ab24e8c6e3ca10ceb5835413f401f90de4bf ]
While reading sysctl_tcp_max_orphans, it can be changed concurrently. So, we need to add READ_ONCE() to avoid a data-race.
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: Sasha Levin sashal@kernel.org --- net/ipv4/tcp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index a3ec2a08027b..19c13ad5c121 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2490,7 +2490,8 @@ static void tcp_orphan_update(struct timer_list *unused)
static bool tcp_too_many_orphans(int shift) { - return READ_ONCE(tcp_orphan_cache) << shift > sysctl_tcp_max_orphans; + return READ_ONCE(tcp_orphan_cache) << shift > + READ_ONCE(sysctl_tcp_max_orphans); }
bool tcp_check_oom(struct sock *sk, int shift)