[PATCH 5.15 04/28] bcache: memset on stack variables in bch_btree_check() and bch_sectors_dirty_init()

From: Greg Kroah-Hartman
Date: Thu Jun 30 2022 - 10:09:28 EST


From: Coly Li <colyli@xxxxxxx>

commit 7d6b902ea0e02b2a25c480edf471cbaa4ebe6b3c upstream.

The local variables check_state (in bch_btree_check()) and state (in
bch_sectors_dirty_init()) should be fully filled by 0, because before
allocating them on stack, they were dynamically allocated by kzalloc().

Signed-off-by: Coly Li <colyli@xxxxxxx>
Link: https://lore.kernel.org/r/20220527152818.27545-2-colyli@xxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/bcache/btree.c | 1 +
drivers/md/bcache/writeback.c | 1 +
2 files changed, 2 insertions(+)

--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -2017,6 +2017,7 @@ int bch_btree_check(struct cache_set *c)
if (c->root->level == 0)
return 0;

+ memset(&check_state, 0, sizeof(struct btree_check_state));
check_state.c = c;
check_state.total_threads = bch_btree_chkthread_nr();
check_state.key_idx = 0;
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -947,6 +947,7 @@ void bch_sectors_dirty_init(struct bcach
return;
}

+ memset(&state, 0, sizeof(struct bch_dirty_init_state));
state.c = c;
state.d = d;
state.total_threads = bch_btre_dirty_init_thread_nr();