From: Jan Beulich <jbeulich@xxxxxxxx>
commit 2991397d23ec597405b116d96de3813420bdcbc3 upstream.
Commit 3194a1746e8a ("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@xxxxxxxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Link: https://lore.kernel.org/r/d933f495-619a-0086-5fb4-1ec3cf81a8fc@xxxxxxxx
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/xen-netback/netback.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -1342,11 +1342,21 @@ int xenvif_tx_action(struct xenvif_queue
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);
