4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka <mpatocka@xxxxxxxxxx> commit 1e1132ea21da6d7be92a72195204379c819cb70b upstream. wc->dirty_bitmap_size is in bytes so must multiply it by 8, not by BITS_PER_LONG, to get number of bitmap_bits. Fixes crash in find_next_bit() that was reported: https://bugzilla.kernel.org/show_bug.cgi?id=200819 Reported-by: edo.rus@xxxxxxxxx Fixes: 48debafe4f2f ("dm: add writecache target") Cc: stable@xxxxxxxxxxxxxxx # 4.18 Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/dm-writecache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -457,7 +457,7 @@ static void ssd_commit_flushed(struct dm COMPLETION_INITIALIZER_ONSTACK(endio.c), ATOMIC_INIT(1), }; - unsigned bitmap_bits = wc->dirty_bitmap_size * BITS_PER_LONG; + unsigned bitmap_bits = wc->dirty_bitmap_size * 8; unsigned i = 0; while (1) {
