From: Aurelien Jacobs <aurel@gnuage.org>
Date: Sat, 7 Jan 2012 20:15:16 +0000 (-0800)
Subject: asix: fix infinite loop in rx_fixup()
X-Git-Tag: v3.2.1~4
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4a75c219087a4079e668c3e5836d64009446c0d3;p=pandora-kernel.git

asix: fix infinite loop in rx_fixup()

commit 6c15d74defd38e7e7f8805392578b7a1d508097e upstream.

At this point if skb->len happens to be 2, the subsequant skb_pull(skb, 4)
call won't work and the skb->len won't be decreased and won't ever reach 0,
resulting in an infinite loop.

With an ASIX 88772 under heavy load, without this patch, rx_fixup() reaches
an infinite loop in less than a minute. With this patch applied,
no infinite loop even after hours of heavy load.

Signed-off-by: Aurelien Jacobs <aurel@gnuage.org>
Cc: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/usb/asix.c b/drivers/net/usb/asix.c
index e95f0e60a9bc..dd2625a3371a 100644
--- a/drivers/net/usb/asix.c
+++ b/drivers/net/usb/asix.c
@@ -376,7 +376,7 @@ static int asix_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 
 		skb_pull(skb, (size + 1) & 0xfffe);
 
-		if (skb->len == 0)
+		if (skb->len < sizeof(header))
 			break;
 
 		head = (u8 *) skb->data;