6.6-stable review patch. If anyone has any objections, please let me know.
------------------
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/rw.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
--- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -549,15 +549,19 @@ static inline int io_rw_prep_async(struc struct iovec *iov; int ret;
+ iorw->bytes_done = 0; + iorw->free_iovec = NULL; + /* submission path, ->uring_lock should already be taken */ ret = io_import_iovec(rw, req, &iov, &iorw->s, 0); 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; + } + return 0; }