On 1/22/24 12:27 PM, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
>
> The patch below does not apply to the 5.15-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@xxxxxxxxxxxxxxx>.
This one applies to 5.10 and 5.15 stable, it should go into both.
It's the same patch, just in the older bigger unified file.
--
Jens Axboe
From 2fb96ecf68bc1fb55508d22ebaf9518eaeb1a088 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@xxxxxxxxx>
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@xxxxxxxxxxxxxxx
Reported-by: xingwei lee <xrivendell7@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
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 30535d4edee7..55fd6d98fe12 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -3490,14 +3490,17 @@ 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;
}
--
2.43.0
