From 74b9a1dbfa806e5d8a45c82f4ebb85587b4f7997 Mon Sep 17 00:00:00 2001 From: Joe Thornber Date: Tue, 13 Apr 2021 09:11:53 +0100 Subject: [PATCH] dm space map common: fix division bug in sm_ll_find_free_block() commit 5208692e80a1f3c8ce2063a22b675dd5589d1d80 upstream. This division bug meant the search for free metadata space could skip the final allocation bitmap's worth of entries. Fix affects DM thinp, cache and era targets. Cc: stable@vger.kernel.org Signed-off-by: Joe Thornber Tested-by: Ming-Hung Tsai Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/persistent-data/dm-space-map-common.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/md/persistent-data/dm-space-map-common.c b/drivers/md/persistent-data/dm-space-map-common.c index 22729fd92a1b..ca09ad2a639c 100644 --- a/drivers/md/persistent-data/dm-space-map-common.c +++ b/drivers/md/persistent-data/dm-space-map-common.c @@ -337,6 +337,8 @@ int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin, */ begin = do_div(index_begin, ll->entries_per_block); end = do_div(end, ll->entries_per_block); + if (end == 0) + end = ll->entries_per_block; for (i = index_begin; i < index_end; i++, begin = 0) { struct dm_block *blk;