diff mbox series

[1/4] fuse: {io-uring} Use READ_ONCE in fuse_uring_send_in_task

Message ID 20250124-optimize-fuse-uring-req-timeouts-v1-1-b834b5f32e85@ddn.com (mailing list archive)
State New
Headers show
Series fuse: {io-uring} Ensure fuse requests are set/read with locks | expand

Commit Message

Bernd Schubert Jan. 24, 2025, 4:46 p.m. UTC 
The value is read from another task without, while the task that
had set the value was holding queue->lock. Better use READ_ONCE
to ensure the compiler cannot optimize the read.

Fixes: 284985711dc5 ("fuse: Allow to queue fg requests through io-uring")
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
---
 fs/fuse/dev_uring.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c
index 5c9b5a5fb7f7539149840378e224eb640cf8ef08..1834c1933d2bbab0342257fde4b030f06506c55d 100644
--- a/fs/fuse/dev_uring.c
+++ b/fs/fuse/dev_uring.c
@@ -1202,10 +1202,12 @@  static void fuse_uring_send_in_task(struct io_uring_cmd *cmd,
 {
 	struct fuse_ring_ent *ent = uring_cmd_to_ring_ent(cmd);
 	struct fuse_ring_queue *queue = ent->queue;
+	struct fuse_req *req;
 	int err;
 
 	if (!(issue_flags & IO_URING_F_TASK_DEAD)) {
-		err = fuse_uring_prepare_send(ent);
+		req = READ_ONCE(ent->fuse_req);
+		err = fuse_uring_prepare_send(ent, req);
 		if (err) {
 			fuse_uring_next_fuse_req(ent, queue, issue_flags);
 			return;