[PATCH RT 2/3] aio: Fix incorrect usage of eventfd_signal_allowed()

From: zanussi
Date: Wed Mar 09 2022 - 10:28:07 EST


From: Xie Yongji <xieyongji@xxxxxxxxxxxxx>

v5.4.182-rt71-rc1 stable review patch.
If anyone has any objections, please let me know.

-----------


[ Upstream commmit 4b3749865374899e115aa8c48681709b086fe6d3 ]

We should defer eventfd_signal() to the workqueue when
eventfd_signal_allowed() return false rather than return
true.

Fixes: b542e383d8c0 ("eventfd: Make signal recursion protection a task bit")
Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210913111928.98-1-xieyongji@xxxxxxxxxxxxx
Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx>
---
fs/aio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/aio.c b/fs/aio.c
index db21ca695781..0bb9abf39065 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1767,7 +1767,7 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
list_del_init(&req->wait.entry);
list_del(&iocb->ki_list);
iocb->ki_res.res = mangle_poll(mask);
- if (iocb->ki_eventfd && eventfd_signal_allowed()) {
+ if (iocb->ki_eventfd && !eventfd_signal_allowed()) {
iocb = NULL;
INIT_WORK(&req->work, aio_poll_put_work);
schedule_work(&req->work);
--
2.17.1