[PATCH 6.6 023/158] io_uring: Fix io_cqring_wait() not restoring sigmask on get_timespec64() failure

Greg Kroah-Hartman
2024-04-23T21:43:09Z

From: Alexey Izbyshev <izbyshev@ispras.ru>

Commit 978e5c19dfefc271e5550efba92fcef0d3f62864 upstream.

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@vger.kernel.org
Fixes: 950e79dd7313 ("io_uring: minor io_cqring_wait() optimization")
Signed-off-by: Alexey Izbyshev <izbyshev@ispras.ru>
Link: https://lore.kernel.org/r/20240405125551.237142-1-izbyshev@ispras.ru
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
io_uring/io_uring.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)

--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -2559,19 +2559,6 @@ static int io_cqring_wait(struct io_ring
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);
@@ -2588,6 +2575,19 @@ static int io_cqring_wait(struct io_ring
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);