[PATCH 4/4] iomap: don't free integrity payload that doesn't exist

[Christoph Hellwig <hch@lst.de>]

fs_bio_integrity_alloc might not allocate a bio integrity payload if PI
verification is disabled on the block device.  Check for that case before
calling fs_bio_integirty_free in iomap_bio_read_folio_range_sync to
avoid a NULL pointer dereferences.

Make the branch cover the PI verification as well - while
fs_bio_integrity_verify works without an integrity payload, it requires
one to actually do useful work.

Fixes: 0b10a370529c ("iomap: support T10 protection information")
Cc: <stable@vger.kernel.org> # v7.1
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
---
 fs/iomap/bio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/iomap/bio.c b/fs/iomap/bio.c
index dc8ac7e370a5..30ef78a66b4f 100644
--- a/fs/iomap/bio.c
+++ b/fs/iomap/bio.c
@@ -179,7 +179,7 @@ int iomap_bio_read_folio_range_sync(const struct iomap_iter *iter,
 	if (srcmap->flags & IOMAP_F_INTEGRITY)
 		fs_bio_integrity_alloc(&bio);
 	error = submit_bio_wait(&bio);
-	if (srcmap->flags & IOMAP_F_INTEGRITY) {
+	if (bio_integrity(&bio)) {
 		if (!error)
 			error = fs_bio_integrity_verify(&bio, sector, len);
 		fs_bio_integrity_free(&bio);
-- 
2.53.0