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| 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 17:27:16 +0100 |
| commit | 4633a79ff8bc82770486a063a08b55e5162521d8 (patch) | |
| tree | e82bcd05d053c2a0ea51c194dd4bca923d0f52e3 | |
| parent | 3d7b7272ce9deb7157670f584274f37d8b12f81f (diff) | |
| download | linux-stable-4633a79ff8bc82770486a063a08b55e5162521d8.tar.gz linux-stable-4633a79ff8bc82770486a063a08b55e5162521d8.tar.bz2 linux-stable-4633a79ff8bc82770486a063a08b55e5162521d8.zip | |
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>
| -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 a6fb6a0b4295..25f1ed261100 100644 --- a/block/bio.c +++ b/block/bio.c @@ -567,7 +567,8 @@ 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; |