Commit d8f00d27 authored Oct 17, 2014 by Li RongQing Committed by David S. Miller Oct 17, 2014

ipv4: fix a potential use after free in fou.c



pskb_may_pull() maybe change skb->data and make uh pointer oboslete,
so reload uh and guehdr

Fixes: 37dd0247 ("gue: Receive side for Generic UDP Encapsulation")
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 1245dfc8

net/ipv4/fou.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -87,6 +87,9 @@ static int gue_udp_recv(struct sock sk, struct sk_buff skb)
		if (!pskb_may_pull(skb, len))
		goto drop;

		uh = udp_hdr(skb);
		guehdr = (struct guehdr *)&uh[1];

		if (guehdr->version != 0)
		goto drop;