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
| ||
|
Date: Thu, 27 Mar 2014 12:56:13 +0000 From: Paul Durrant <paul.durrant@...rix.com> To: <xen-devel@...ts.xen.org>, <netdev@...r.kernel.org> CC: Paul Durrant <paul.durrant@...rix.com>, Ian Campbell <ian.campbell@...rix.com>, Wei Liu <wei.liu2@...rix.com>, Sander Eikelenboom <linux@...elenboom.it> Subject: [PATCH net v2 3/3] xen-netback: BUG_ON in xenvif_rx_action() not catching overflow The BUG_ON to catch ring overflow in xenvif_rx_action() makes the assumption that meta_slots_used == ring slots used. This is not necessarily the case for GSO packets, because the non-prefix GSO protocol consumes one more ring slot than meta-slot for the 'extra_info'. This patch changes the test to actually check ring slots. Signed-off-by: Paul Durrant <paul.durrant@...rix.com> Cc: Ian Campbell <ian.campbell@...rix.com> Cc: Wei Liu <wei.liu2@...rix.com> Cc: Sander Eikelenboom <linux@...elenboom.it> --- v2: - Add explanation as to why meta_slots_used != ring slots used drivers/net/xen-netback/netback.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index aa87ae8..cbe6d6a 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -482,6 +482,8 @@ static void xenvif_rx_action(struct xenvif *vif) while ((skb = skb_dequeue(&vif->rx_queue)) != NULL) { RING_IDX max_slots_needed; + RING_IDX old_req_cons; + RING_IDX ring_slots_used; int i; /* We need a cheap worse case estimate for the number of @@ -521,8 +523,12 @@ static void xenvif_rx_action(struct xenvif *vif) vif->rx_last_skb_slots = 0; sco = (struct skb_cb_overlay *)skb->cb; + + old_req_cons = vif->rx.req_cons; sco->meta_slots_used = xenvif_gop_skb(skb, &npo); - BUG_ON(sco->meta_slots_used > max_slots_needed); + ring_slots_used = vif->rx.req_cons - old_req_cons; + + BUG_ON(ring_slots_used > max_slots_needed); __skb_queue_tail(&rxq, skb); } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists