Patch "io_uring: Fix io_cqring_wait() not restoring sigmask on get_timespec64() failure" has been added to the 6.8-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    io_uring: Fix io_cqring_wait() not restoring sigmask on get_timespec64() failure

to the 6.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     io_uring-fix-io_cqring_wait-not-restoring-sigmask-on.patch
and it can be found in the queue-6.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 80eb4b220963a07c2d5f7a5f96a722e906c933e2
Author: Alexey Izbyshev <izbyshev@xxxxxxxxx>
Date:   Fri Apr 5 15:55:51 2024 +0300

    io_uring: Fix io_cqring_wait() not restoring sigmask on get_timespec64() failure
    
    [ Upstream commit 978e5c19dfefc271e5550efba92fcef0d3f62864 ]
    
    This bug was introduced in commit 950e79dd7313 ("io_uring: minor
    io_cqring_wait() optimization"), which was made in preparation for
    adc8682ec690 ("io_uring: Add support for napi_busy_poll"). The latter
    got reverted in cb3182167325 ("Revert "io_uring: Add support for
    napi_busy_poll""), so simply undo the former as well.
    
    Cc: stable@xxxxxxxxxxxxxxx
    Fixes: 950e79dd7313 ("io_uring: minor io_cqring_wait() optimization")
    Signed-off-by: Alexey Izbyshev <izbyshev@xxxxxxxxx>
    Link: https://lore.kernel.org/r/20240405125551.237142-1-izbyshev@xxxxxxxxx
    Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 3fc792dfc6ae7..dc0235ff472d3 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -2610,19 +2610,6 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
 	if (__io_cqring_events_user(ctx) >= min_events)
 		return 0;
 
-	if (sig) {
-#ifdef CONFIG_COMPAT
-		if (in_compat_syscall())
-			ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
-						      sigsz);
-		else
-#endif
-			ret = set_user_sigmask(sig, sigsz);
-
-		if (ret)
-			return ret;
-	}
-
 	init_waitqueue_func_entry(&iowq.wq, io_wake_function);
 	iowq.wq.private = current;
 	INIT_LIST_HEAD(&iowq.wq.entry);
@@ -2639,6 +2626,19 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
 		iowq.timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns());
 	}
 
+	if (sig) {
+#ifdef CONFIG_COMPAT
+		if (in_compat_syscall())
+			ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
+						      sigsz);
+		else
+#endif
+			ret = set_user_sigmask(sig, sigsz);
+
+		if (ret)
+			return ret;
+	}
+
 	trace_io_uring_cqring_wait(ctx, min_events);
 	do {
 		int nr_wait = (int) iowq.cq_tail - READ_ONCE(ctx->rings->cq.tail);