From 0139c17d0314affb007558a7b0818830f2704061 Mon Sep 17 00:00:00 2001 From: Gen Zhang Date: Fri, 24 May 2019 11:19:46 +0800 Subject: [PATCH] ipv6_sockglue: Fix a missing-check bug in ip6_ra_control() In function ip6_ra_control(), the pointer new_ra is allocated a memory space via kmalloc(). And it is used in the following codes. However, when there is a memory allocation error, kmalloc() fails. Thus null pointer dereference may happen. And it will cause the kernel to crash. Therefore, we should check the return value and handle the error. Signed-off-by: Gen Zhang Signed-off-by: David S. Miller --- net/ipv6/ipv6_sockglue.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 40f21fef25ff4..0a3d035feb616 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -68,6 +68,8 @@ int ip6_ra_control(struct sock *sk, int sel) return -ENOPROTOOPT; new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; + if (sel >= 0 && !new_ra) + return -ENOMEM; write_lock_bh(&ip6_ra_lock); for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) { -- 2.39.5