Mailing List Archive

[patch] xen-gntdev: integer overflow in gntdev_alloc_map()
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@oracle.com>

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@lists.xensource.com
http://lists.xensource.com/xen-devel