Commit 1728786b authored Apr 25, 2017 by Myungho Jung Committed by Greg Kroah-Hartman Oct 08, 2017

net: core: Prevent from dereferencing null pointer when releasing SKB


[ Upstream commit 9899886d5e8ec5b343b1efe44f185a0e68dc6454 ]

Added NULL check to make __dev_kfree_skb_irq consistent with kfree
family of functions.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289



Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4c963eff

net/core/dev.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -2225,6 +2225,9 @@ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
		{
		unsigned long flags;

		if (unlikely(!skb))
		return;

		if (likely(atomic_read(&skb->users) == 1)) {
		smp_rmb();
		atomic_set(&skb->users, 0);