From 8c0b563e9b4d5a4bed51667816e487120d2eb696 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 22 Jan 2024 12:30:07 -0700 Subject: [PATCH] io_uring/rw: ensure io->bytes_done is always initialized commit 0a535eddbe0dc1de4386046ab849f08aeb2f8faf 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 Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/io_uring.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index aa15e8d878a9..936abc6ee450 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -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; }