[PATCH] bridge: fix possible overflow in get_fdb_entries

Make sure to properly clamp maxnum to avoid overflow

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Eugene Teo <eteo@redhat.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Chris Wright 2006-11-20 15:02:49 -08:00 committed by Linus Torvalds
parent 24d7bb3396
commit ba8379b220

View file

@ -58,12 +58,13 @@ static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
{
int num;
void *buf;
size_t size = maxnum * sizeof(struct __fdb_entry);
size_t size;
if (size > PAGE_SIZE) {
size = PAGE_SIZE;
/* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */
if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry))
maxnum = PAGE_SIZE/sizeof(struct __fdb_entry);
}
size = maxnum * sizeof(struct __fdb_entry);
buf = kmalloc(size, GFP_USER);
if (!buf)