5.10-stable review patch. If anyone has any objections, please let me know.
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From: Jens Axboe axboe@kernel.dk
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 xrivendell7@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/io_uring.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
--- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3485,14 +3485,17 @@ static inline int io_rw_prep_async(struc 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; }