diff options
| author | Jens Axboe <axboe@kernel.dk> | 2025-01-23 06:18:41 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-17 10:05:19 +0100 |
| commit | 68f16d3034a06661245ecd22f0d586a8b4e7c473 (patch) | |
| tree | 29ff194281caf65130094408ddd66ee534f8ff28 | |
| parent | 8a844ea6d73f2311bd5f19bd287d8c55ba4239e8 (diff) | |
block: don't revert iter for -EIOCBQUEUED
commit b13ee668e8280ca5b07f8ce2846b9957a8a10853 upstream.
blkdev_read_iter() has a few odd checks, like gating the position and
count adjustment on whether or not the result is bigger-than-or-equal to
zero (where bigger than makes more sense), and not checking the return
value of blkdev_direct_IO() before doing an iov_iter_revert(). The
latter can lead to attempting to revert with a negative value, which
when passed to iov_iter_revert() as an unsigned value will lead to
throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT.
Be sane and don't revert for -EIOCBQUEUED, like what is done in other
spots.
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | block/fops.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/block/fops.c b/block/fops.c index 13a67940d040..43983be5a2b3 100644 --- a/block/fops.c +++ b/block/fops.c @@ -758,11 +758,12 @@ static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) file_accessed(iocb->ki_filp); ret = blkdev_direct_IO(iocb, to); - if (ret >= 0) { + if (ret > 0) { iocb->ki_pos += ret; count -= ret; } - iov_iter_revert(to, count - iov_iter_count(to)); + if (ret != -EIOCBQUEUED) + iov_iter_revert(to, count - iov_iter_count(to)); if (ret < 0 || !count) goto reexpand; } |