diff options
| author | OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> | 2022-01-09 18:36:43 +0900 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-01-20 06:30:12 -0700 |
| commit | 3ee859e384d453d6ac68bfd5971f630d9fa46ad3 (patch) | |
| tree | 16e2d6b6407e50614f4f0c6ef9882305cd5fd27f | |
| parent | fd9f4e62a39f09a7c014d7415c2b9d1390aa0504 (diff) | |
block: Fix wrong offset in bio_truncate()
bio_truncate() clears the buffer outside of last block of bdev, however
current bio_truncate() is using the wrong offset of page. So it can
return the uninitialized data.
This happened when both of truncated/corrupted FS and userspace (via
bdev) are trying to read the last of bdev.
Reported-by: syzbot+ac94ae5f68b84197f41c@syzkaller.appspotmail.com
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/875yqt1c9g.fsf@mail.parknet.co.jp
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/bio.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/block/bio.c b/block/bio.c index 0d400ba2dbd1..4312a8085396 100644 --- a/block/bio.c +++ b/block/bio.c @@ -569,7 +569,8 @@ static void bio_truncate(struct bio *bio, unsigned new_size) offset = new_size - done; else offset = 0; - zero_user(bv.bv_page, offset, bv.bv_len - offset); + zero_user(bv.bv_page, bv.bv_offset + offset, + bv.bv_len - offset); truncated = true; } done += bv.bv_len; |