linux-kernel - [v2.6.34-stable 024/165] atm: br2684: Fix oops due to skb->dev being NULL

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]

Date:	Wed, 15 Aug 2012 15:46:08 -0400
From:	Paul Gortmaker <paul.gortmaker@...driver.com>
To:	<stable@...r.kernel.org>, <linux-kernel@...r.kernel.org>
CC:	Daniel Schwierzeck <daniel.schwierzeck@...glemail.com>,
	"David S. Miller" <davem@...emloft.net>,
	Paul Gortmaker <paul.gortmaker@...driver.com>
Subject: [v2.6.34-stable 024/165] atm: br2684: Fix oops due to skb->dev being NULL

From: Daniel Schwierzeck <daniel.schwierzeck@...glemail.com>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit fbe5e29ec1886967255e76946aaf537b8cc9b81e upstream.

This oops have been already fixed with commit

    27141666b69f535a4d63d7bc6d9e84ee5032f82a

    atm: [br2684] Fix oops due to skb->dev being NULL

    It happens that if a packet arrives in a VC between the call to open it on
    the hardware and the call to change the backend to br2684, br2684_regvcc
    processes the packet and oopses dereferencing skb->dev because it is
    NULL before the call to br2684_push().

but have been introduced again with commit

    b6211ae7f2e56837c6a4849316396d1535606e90

    atm: Use SKB queue and list helpers instead of doing it by-hand.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@...glemail.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@...driver.com>
---
 net/atm/br2684.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/atm/br2684.c b/net/atm/br2684.c
index f3bae14..e9b5677 100644
--- a/net/atm/br2684.c
+++ b/net/atm/br2684.c
@@ -522,12 +522,13 @@ static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
 	spin_unlock_irqrestore(&rq->lock, flags);
 
 	skb_queue_walk_safe(&queue, skb, tmp) {
-		struct net_device *dev = skb->dev;
+		struct net_device *dev;
+
+		br2684_push(atmvcc, skb);
+		dev = skb->dev;
 
 		dev->stats.rx_bytes -= skb->len;
 		dev->stats.rx_packets--;
-
-		br2684_push(atmvcc, skb);
 	}
 	__module_get(THIS_MODULE);
 	return 0;
-- 
1.7.12.rc2

--
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/