dm table: fail dm_table_create on dm_round_up overflow
The dm_round_up function may overflow to zero. In this case,
dm_table_create() must fail rather than go on to allocate an empty array
with alloc_targets().
This fixes a possible memory corruption that could be caused by passing
too large a number in "param->target_count".
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 465f08c..3ba6a38 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -200,6 +200,11 @@
num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
+ if (!num_targets) {
+ kfree(t);
+ return -ENOMEM;
+ }
+
if (alloc_targets(t, num_targets)) {
kfree(t);
return -ENOMEM;