From 5b2d06576c5410c10d95adfd5c4d8b24de861d87 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 22 Nov 2013 19:52:06 -0500 Subject: [PATCH] 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 Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org --- drivers/md/dm-table.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 465f08ca62b1..3ba6a3859ce3 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -200,6 +200,11 @@ int dm_table_create(struct dm_table **result, fmode_t mode, 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;