This is a note to let you know that I've just added the patch titled xen-netfront: restore __skb_queue_tail() positioning in xennet_get_responses() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xen-netfront-restore-__skb_queue_tail-positioning-in-xennet_get_responses.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue Jul 5 12:56:39 PM CEST 2022 From: Jan Beulich <jbeulich@xxxxxxxx> Date: Fri, 1 Jul 2022 09:57:19 +0200 Subject: xen-netfront: restore __skb_queue_tail() positioning in xennet_get_responses() From: Jan Beulich <jbeulich@xxxxxxxx> commit f63c2c2032c2e3caad9add3b82cc6e91c376fd26 upstream. The commit referenced below moved the invocation past the "next" label, without any explanation. In fact this allows misbehaving backends undue control over the domain the frontend runs in, as earlier detected errors require the skb to not be freed (it may be retained for later processing via xennet_move_rx_slot(), or it may simply be unsafe to have it freed). This is CVE-2022-33743 / XSA-405. Fixes: 6c5aa6fc4def ("xen networking: add basic XDP support for xen-netfront") Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> Reviewed-by: Juergen Gross <jgross@xxxxxxxx> Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/xen-netfront.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1094,8 +1094,10 @@ static int xennet_get_responses(struct n } } rcu_read_unlock(); -next: + __skb_queue_tail(list, skb); + +next: if (!(rx->flags & XEN_NETRXF_more_data)) break; Patches currently in stable-queue which might be from jbeulich@xxxxxxxx are queue-5.15/xen-netfront-fix-leaking-data-in-shared-pages.patch queue-5.15/xen-blkfront-fix-leaking-data-in-shared-pages.patch queue-5.15/xen-netfront-restore-__skb_queue_tail-positioning-in-xennet_get_responses.patch