From 833309f3fb511b4e4873a0a39b8be7ac747d6d3d Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Sun, 22 Mar 2020 20:42:21 +0100 Subject: [PATCH] dm integrity: fix a crash with unusually large tag size commit b93b6643e9b5a7f260b931e97f56ffa3fa65e26d upstream. If the user specifies tag size larger than HASH_MAX_DIGESTSIZE, there's a crash in integrity_metadata(). Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-integrity.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 145bc2e..5624877 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1514,7 +1514,7 @@ static void integrity_metadata(struct work_struct *w) struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); char *checksums; unsigned extra_space = unlikely(digest_size > ic->tag_size) ? digest_size - ic->tag_size : 0; - char checksums_onstack[HASH_MAX_DIGESTSIZE]; + char checksums_onstack[max((size_t)HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; unsigned sectors_to_process = dio->range.n_sectors; sector_t sector = dio->range.logical_sector; @@ -1743,7 +1743,7 @@ retry_kmap: } while (++s < ic->sectors_per_block); #ifdef INTERNAL_VERIFY if (ic->internal_hash) { - char checksums_onstack[max(HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; + char checksums_onstack[max((size_t)HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; integrity_sector_checksum(ic, logical_sector, mem + bv.bv_offset, checksums_onstack); if (unlikely(memcmp(checksums_onstack, journal_entry_tag(ic, je), ic->tag_size))) { -- 2.7.4