[PATCH][V2][next] dm space maps: Fix uninitialized variable r2

From: Colin King
Date: Fri May 21 2021 - 05:51:10 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

In the case where recursing(mm) is true variable r2 is not
inintialized and an uninitialized value is being used in the
call combine_errors later on. Fix this by setting r2 to zero.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: def6a7a9a7f0 ("dm space maps: improve performance with inc/dec on ranges of blocks")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---

V2: Add fix in function sm_metadata_inc_blocks

---
drivers/md/persistent-data/dm-space-map-metadata.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/md/persistent-data/dm-space-map-metadata.c b/drivers/md/persistent-data/dm-space-map-metadata.c
index 3b70ee861cf5..a9a362777fad 100644
--- a/drivers/md/persistent-data/dm-space-map-metadata.c
+++ b/drivers/md/persistent-data/dm-space-map-metadata.c
@@ -417,6 +417,7 @@ static int sm_metadata_inc_blocks(struct dm_space_map *sm, dm_block_t b, dm_bloc
r = add_bop(smm, BOP_INC, b, e);
if (r)
return r;
+ r2 = 0;
} else {
in(smm);
r = sm_ll_inc(&smm->ll, b, e, &nr_allocations);
@@ -432,9 +433,10 @@ static int sm_metadata_dec_blocks(struct dm_space_map *sm, dm_block_t b, dm_bloc
int32_t nr_allocations;
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);

- if (recursing(smm))
+ if (recursing(smm)) {
r = add_bop(smm, BOP_DEC, b, e);
- else {
+ r2 = 0;
+ } else {
in(smm);
r = sm_ll_dec(&smm->ll, b, e, &nr_allocations);
r2 = out(smm);
--
2.31.1