linux-kernel - [PATCH net 2/4] xen-netback: Fix releasing frag

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1405624192-21722-3-git-send-email-zoltan.kiss@citrix.com>
Date:	Thu, 17 Jul 2014 20:09:50 +0100
From:	Zoltan Kiss <zoltan.kiss@...rix.com>
To:	Wei Liu <wei.liu2@...rix.com>,
	Ian Campbell <Ian.Campbell@...rix.com>
CC:	Zoltan Kiss <zoltan.kiss@...rix.com>, <netdev@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>, <xen-devel@...ts.xenproject.org>
Subject: [PATCH net 2/4] xen-netback: Fix releasing frag_list skbs in error path

When the grant operations failed, the skb is freed up eventually, and it tries
to release the frags, if there is any. For the main skb nr_frags is set to 0 to
avoid this, but on the frag_list it iterates through the frags array, and tries
to call put_page on the page pointer which contains garbage at that time.

Signed-off-by: Zoltan Kiss <zoltan.kiss@...rix.com>
Reported-by: Armin Zentai <armin.zentai@...t.hu>
Cc: netdev@...r.kernel.org
Cc: linux-kernel@...r.kernel.org
Cc: xen-devel@...ts.xenproject.org
---
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 604ff71..e9ffb05 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -1522,6 +1522,11 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
 		/* Check the remap error code. */
 		if (unlikely(xenvif_tx_check_gop(queue, skb, &gop_map, &gop_copy))) {
 			skb_shinfo(skb)->nr_frags = 0;
+			if (skb_has_frag_list(skb)) {
+				struct sk_buff *nskb =
+						skb_shinfo(skb)->frag_list;
+				skb_shinfo(nskb)->nr_frags = 0;
+			}
 			kfree_skb(skb);
 			continue;
 		}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/