From f79c83d6c41930362bc66fc71489e92975a2facf Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Mon, 2 Nov 2015 07:50:07 -0800
Subject: [PATCH] net: avoid NULL deref in inet_ctl_sock_destroy()
[ Upstream commit 8fa677d2706d325d71dab91bf6e6512c05214e37 ]
Under low memory conditions, tcp_sk_init() and icmp_sk_init()
can both iterate on all possible cpus and call inet_ctl_sock_destroy(),
with eventual NULL pointer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
include/net/inet_common.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/net/inet_common.h b/include/net/inet_common.h
index 22fac9892b160..df3be8f857c54 100644
--- a/include/net/inet_common.h
+++ b/include/net/inet_common.h
@@ -38,7 +38,8 @@ extern int inet_ctl_sock_create(struct sock **sk, unsigned short family,
static inline void inet_ctl_sock_destroy(struct sock *sk)
{
- sk_release_kernel(sk);
+ if (sk)
+ sk_release_kernel(sk);
}
#endif