bio_integrity_add_page() already sets bip_vcnt to 1 for the bounce segment. Overwriting it with nr_vecs breaks bip_vcnt <= bip_max_vcnt on WRITE (bip_max_vcnt is 1), so the gap-merge checks in block/blk.h read past the bip_vec[] flex array. On READ the read is in bounds but lands on a saved user bvec instead of the bounce. The line was added for split propagation, but bio_integrity_clone() doesn't copy bip_vcnt and BIP_CLONE_FLAGS excludes BIP_COPY_USER. Fixes: 3991657ae707 ("block: set bip_vcnt correctly") Signed-off-by: David Carlier --- block/bio-integrity.c | 1 - 1 file changed, 1 deletion(-) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index e79eaf047794..869746412949 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -308,7 +308,6 @@ static int bio_integrity_copy_user(struct bio *bio, struct bio_vec *bvec, } bip->bip_flags |= BIP_COPY_USER; - bip->bip_vcnt = nr_vecs; return 0; free_bip: bio_integrity_free(bio); -- 2.53.0