[PATCH 5.14 132/162] block: check if a profile is actually registered in blk_integrity_unregister

[Greg Kroah-Hartman]

From: Christoph Hellwig <hch@xxxxxx>

[ Upstream commit 783a40a1b3ac7f3714d2776fa8ac8cce3535e4f6 ]

While clearing the profile itself is harmless, we really should not clear
the stable writes flag if it wasn't set due to a registered integrity
profile.

Reported-by: Lihong Kou <koulihong@xxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210914070657.87677-2-hch@xxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 block/blk-integrity.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 410da060d1f5..e9f943de377a 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -426,8 +426,12 @@ EXPORT_SYMBOL(blk_integrity_register);
  */
 void blk_integrity_unregister(struct gendisk *disk)
 {
+	struct blk_integrity *bi = &disk->queue->integrity;
+
+	if (!bi->profile)
+		return;
 	blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, disk->queue);
-	memset(&disk->queue->integrity, 0, sizeof(struct blk_integrity));
+	memset(bi, 0, sizeof(*bi));
 }
 EXPORT_SYMBOL(blk_integrity_unregister);
 
-- 
2.33.0