diff options
| author | OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> | 2022-01-09 18:36:43 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-01 17:24:39 +0100 |
| commit | 6cbf4c731d7812518cd857c2cfc3da9fd120f6ae (patch) | |
| tree | 7617cec8752acb3f8adbd9166a562b8a9d842826 /block | |
| parent | 33a9ba52d5ea55a1e80f61022857bb705074aaf8 (diff) | |
block: Fix wrong offset in bio_truncate()
commit 3ee859e384d453d6ac68bfd5971f630d9fa46ad3 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'block')
| -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 cb38d6f3acce..1c52d0196e15 100644 --- a/block/bio.c +++ b/block/bio.c @@ -569,7 +569,8 @@ 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; |