Commit 2991397d authored by Jan Beulich's avatar Jan Beulich Committed by Juergen Gross
Browse files

xen-netback: respect gnttab_map_refs()'s return value 



Commit 3194a174 ("xen-netback: don't "handle" error by BUG()")
dropped respective a BUG_ON() without noticing that with this the
variable's value wouldn't be consumed anymore. With gnttab_set_map_op()
setting all status fields to a non-zero value, in case of an error no
slot should have a status of GNTST_okay (zero).

This is part of XSA-367.

Cc: <stable@vger.kernel.org>
Reported-by: default avatarkernel test robot <lkp@intel.com>
Signed-off-by: default avatarJan Beulich <jbeulich@suse.com>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/d933f495-619a-0086-5fb4-1ec3cf81a8fc@suse.com


Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
parent 8310b77b

drivers/net/xen-netback/netback.c

+11 −1
Original line number Diff line number Diff line
@@ -1343,11 +1343,21 @@ int xenvif_tx_action(struct xenvif_queue *queue, int budget) 
		return 0;



	gnttab_batch_copy(queue->tx_copy_ops, nr_cops);

	if (nr_mops != 0)

	if (nr_mops != 0) {

		ret = gnttab_map_refs(queue->tx_map_ops,

				      NULL,

				      queue->pages_to_map,

				      nr_mops);

		if (ret) {

			unsigned int i;



			netdev_err(queue->vif->dev, "Map fail: nr %u ret %d\n",

				   nr_mops, ret);

			for (i = 0; i < nr_mops; ++i)

				WARN_ON_ONCE(queue->tx_map_ops[i].status ==

				             GNTST_okay);

		}

	}



	work_done = xenvif_tx_submit(queue);