io_uring/rw: ensure io->bytes_done is always initialized

commit 0a535eddbe upstream.

If IOSQE_ASYNC is set and we fail importing an iovec for a readv or
writev request, then we leave ->bytes_done uninitialized and hence the
eventual failure CQE posted can potentially have a random res value
rather than the expected -EINVAL.

Setup ->bytes_done before potentially failing, so we have a consistent
value if we fail the request early.

Cc: stable@vger.kernel.org
Reported-by: xingwei lee <xrivendell7@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jens Axboe 2024-01-22 12:30:07 -07:00 committed by Greg Kroah-Hartman
parent daa61bacd3
commit 8c0b563e9b
1 changed files with 6 additions and 3 deletions

View File

@ -3485,14 +3485,17 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
struct iovec *iov = iorw->fast_iov;
int ret;
iorw->bytes_done = 0;
iorw->free_iovec = NULL;
ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
if (unlikely(ret < 0))
return ret;
iorw->bytes_done = 0;
iorw->free_iovec = iov;
if (iov)
if (iov) {
iorw->free_iovec = iov;
req->flags |= REQ_F_NEED_CLEANUP;
}
iov_iter_save_state(&iorw->iter, &iorw->iter_state);
return 0;
}