diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2022-10-16 22:42:58 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-10-26 12:35:53 +0200 |
| commit | 98aada6e22786916d150a598c7a7eaf937ca464c (patch) | |
| tree | 7a6259bf009bfee5e0928010429a55799e2469ef /fs | |
| parent | d6b7efc722a2684b6652ee49546c83b544b1b4b6 (diff) | |
io_uring/rw: fix unexpected link breakage
[ upstream commit bf68b5b34311ee57ed40749a1257a30b46127556 ]
req->cqe.res is set in io_read() to the amount of bytes left to be done,
which is used to figure out whether to fail a read or not. However,
io_read() may do another without returning, and we stash the previous
value into ->bytes_done but forget to update cqe.res. Then we ask a read
to do strictly less than cqe.res but expect the return to be exactly
cqe.res.
Fix the bug by updating cqe.res for retries.
Cc: stable@vger.kernel.org
Reported-and-Tested-by: Beld Zhang <beldzhang@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3a1088440c7be98e5800267af922a67da0ef9f13.1664235732.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/io_uring.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 589e9e122e5d..b8ae64df90e3 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3606,6 +3606,7 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags) return -EAGAIN; } + req->result = iov_iter_count(iter); /* * Now retry read with the IOCB_WAITQ parts set in the iocb. If * we get -EIOCBQUEUED, then we'll get a notification when the |