From: Gen Zhang <blackgod016574@xxxxxxxxx> commit 425aa0e1d01513437668fa3d4a971168bbaa8515 upstream. In function ip_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 <blackgod016574@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@xxxxxxxxxxxxx> --- net/ipv4/ip_sockglue.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index b7a2612..faaf688 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -343,6 +343,8 @@ int ip_ra_control(struct sock *sk, unsigned char on, return -EINVAL; new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; + if (on && !new_ra) + return -ENOMEM; mutex_lock(&net->ipv4.ra_mutex); for (rap = &net->ipv4.ra_chain;
