WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] [patch] xen-gntdev: integer overflow in gntdev_alloc_map()

To: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>
Subject: [Xen-devel] [patch] xen-gntdev: integer overflow in gntdev_alloc_map()
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Fri, 4 Nov 2011 21:23:32 +0300
Cc: kernel-janitors@xxxxxxxxxxxxxxx, xen-devel@xxxxxxxxxxxxxxxxxxx, virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx, Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Delivery-date: Mon, 14 Nov 2011 15:33:17 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.21 (2010-09-15)
The multiplications here can overflow resulting in smaller buffer
sizes than expected.  "count" comes from a copy_from_user().

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 880798a..2f3c363 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -114,11 +114,11 @@ static struct grant_map *gntdev_alloc_map(struct 
gntdev_priv *priv, int count)
        if (NULL == add)
                return NULL;
 
-       add->grants    = kzalloc(sizeof(add->grants[0])    * count, GFP_KERNEL);
-       add->map_ops   = kzalloc(sizeof(add->map_ops[0])   * count, GFP_KERNEL);
-       add->unmap_ops = kzalloc(sizeof(add->unmap_ops[0]) * count, GFP_KERNEL);
-       add->kmap_ops  = kzalloc(sizeof(add->kmap_ops[0])  * count, GFP_KERNEL);
-       add->pages     = kzalloc(sizeof(add->pages[0])     * count, GFP_KERNEL);
+       add->grants    = kcalloc(count, sizeof(add->grants[0]), GFP_KERNEL);
+       add->map_ops   = kcalloc(count, sizeof(add->map_ops[0]), GFP_KERNEL);
+       add->unmap_ops = kcalloc(count, sizeof(add->unmap_ops[0]), GFP_KERNEL);
+       add->kmap_ops  = kcalloc(count, sizeof(add->kmap_ops[0]), GFP_KERNEL);
+       add->pages     = kcalloc(count, sizeof(add->pages[0]), GFP_KERNEL);
        if (NULL == add->grants    ||
            NULL == add->map_ops   ||
            NULL == add->unmap_ops ||

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-devel] [patch] xen-gntdev: integer overflow in gntdev_alloc_map(), Dan Carpenter <=