From a86ed8caf2fda2069ed910b42f80d7e7b7bc49d1 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 commit 5b2d06576c5410c10d95adfd5c4d8b24de861d87 upstream. 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 Signed-off-by: Ben Hutchings --- 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 72c0dfb301f0..5c52582b0179 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -215,6 +215,11 @@ 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); t = NULL; -- 2.11.4.GIT