From: Jesper Juhl <jj@chaosbits.net>
Date: Fri, 17 Aug 2012 10:33:12 +0000 (+0000)
Subject: caif: Do not dereference NULL in chnl_recv_cb()
X-Git-Tag: v3.6-rc3~10^2~9
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d92c7f8aabae913de16eb855b19cd2002c341896;p=platform%2Fkernel%2Flinux-3.10.git

caif: Do not dereference NULL in chnl_recv_cb()

In net/caif/chnl_net.c::chnl_recv_cb() we call skb_header_pointer()
which may return NULL, but we do not check for a NULL pointer before
dereferencing it.
This patch adds such a NULL check and properly free's allocated memory
and return an error (-EINVAL) on failure - much better than crashing..

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
index 69771c0..e597733 100644
--- a/net/caif/chnl_net.c
+++ b/net/caif/chnl_net.c
@@ -94,6 +94,10 @@ static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
 
 	/* check the version of IP */
 	ip_version = skb_header_pointer(skb, 0, 1, &buf);
+	if (!ip_version) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
 
 	switch (*ip_version >> 4) {
 	case 4: