From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roel Kluin Subject: Re: [PATCH] 3c515: Write outside array bounds Date: Wed, 29 Jul 2009 16:13:24 +0200 Message-ID: <4A705904.4020505@gmail.com> References: <4A6B88B1.9000907@gmail.com> <4A6CC7BD.9020602@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "David S. Miller" , netdev , Andrew Morton To: Jarek Poplawski Return-path: Received: from mail-ew0-f226.google.com ([209.85.219.226]:59289 "EHLO mail-ew0-f226.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751111AbZG2OKe (ORCPT ); Wed, 29 Jul 2009 10:10:34 -0400 Received: by ewy26 with SMTP id 26so856360ewy.37 for ; Wed, 29 Jul 2009 07:10:32 -0700 (PDT) In-Reply-To: <4A6CC7BD.9020602@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Op 26-07-09 23:16, Jarek Poplawski schreef: > Roel Kluin wrote, On 07/26/2009 12:35 AM: > >> if dev_alloc_skb() fails on the first iteration, a write to >> cp->rx_ring[-1] occurs. >> >> Signed-off-by: Roel Kluin >> --- >> Please review: can we error return like this? > > > I doubt we can return here: there is a lot of cleaning missing. > > Jarek P. I took drivers/net/3c59x.c as an example Is this going in the right direction? diff --git a/drivers/net/3c515.c b/drivers/net/3c515.c index 3e00fa8..e94867d 100644 --- a/drivers/net/3c515.c +++ b/drivers/net/3c515.c @@ -827,7 +827,7 @@ static int corkscrew_open(struct net_device *dev) skb = dev_alloc_skb(PKT_BUF_SZ); vp->rx_skbuff[i] = skb; if (skb == NULL) - break; /* Bad news! */ + goto error; /* Bad news! */ skb->dev = dev; /* Mark as being used by this device. */ skb_reserve(skb, 2); /* Align IP on 16 byte boundaries */ vp->rx_ring[i].addr = isa_virt_to_bus(skb->data); @@ -864,6 +864,17 @@ static int corkscrew_open(struct net_device *dev) ioaddr + EL3_CMD); return 0; +error: + pr_emerg("%s: no memory for rx ring\n", dev->name); + int j; + for (j = 0; j < i; j++) { + if (vp->rx_skbuff[j]) { + dev_kfree_skb(vp->rx_skbuff[j]); + vp->rx_skbuff[j] = NULL; + } + } + free_irq(dev->irq, dev); + return -ENOMEM; } static void corkscrew_timer(unsigned long data)