xen/netfront: fix leaking data in shared pages
authorRoger Pau Monne <roger.pau@citrix.com>
Wed, 6 Apr 2022 15:38:04 +0000 (17:38 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 7 Jul 2022 15:53:31 +0000 (17:53 +0200)
commit 307c8de2b02344805ebead3440d8feed28f2f010 upstream.

When allocating pages to be used for shared communication with the
backend always zero them, this avoids leaking unintended data present
on the pages.

This is CVE-2022-33740, part of XSA-403.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/net/xen-netfront.c

index 2492a27467b46c07037ec7fdc01c54477f09d93d..cae8537115a891461792d80ea7af7b66804e4192 100644 (file)
@@ -273,7 +273,8 @@ static struct sk_buff *xennet_alloc_one_rx_buffer(struct netfront_queue *queue)
        if (unlikely(!skb))
                return NULL;
 
-       page = page_pool_dev_alloc_pages(queue->page_pool);
+       page = page_pool_alloc_pages(queue->page_pool,
+                                    GFP_ATOMIC | __GFP_NOWARN | __GFP_ZERO);
        if (unlikely(!page)) {
                kfree_skb(skb);
                return NULL;