iomap: don't free integrity payload that doesn't exist

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_integrity_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: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Link: https://patch.msgid.link/20260804124404.737145-2-hch@lst.de
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>

diff --git a/fs/iomap/bio.c b/fs/iomap/bio.c
index 4504f4633f17592cbc24a5f102f7b5c00959971a..311199344b282fedde4cd4360508880f0176c307 100644 (file)
--- a/fs/iomap/bio.c
+++ b/fs/iomap/bio.c
@@ -170,7 +170,7 @@ 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);