[PATCH 5.18 223/231] s390/ap: fix error handling in __verify_queue_reservations()

Greg Kroah-Hartman
2022-07-19T13:11:47Z

From: Tony Krowiak <akrowiak@linux.ibm.com>

commit 2f23256c0ea20627c91ea2d468cda945f68c3395 upstream.

The AP bus's __verify_queue_reservations function increments the ref count
for the device driver passed in as a parameter, but fails to decrement it
before returning control to the caller. This will prevents any subsequent
removal of the module.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reported-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Fixes: 4f8206b88286 ("s390/ap: driver callback to indicate resource in use")
Link: https://lore.kernel.org/r/20220706222619.602094-1-akrowiak@linux.ibm.com
Cc: stable@vger.kernel.org
[agordeev@linux.ibm.com fixed description, added Fixes and Link]
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/s390/crypto/ap_bus.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -1410,7 +1410,7 @@ static int __verify_queue_reservations(s
if (ap_drv->in_use) {
rc = ap_drv->in_use(ap_perms.apm, newaqm);
if (rc)
- return -EBUSY;
+ rc = -EBUSY;
}

/* release the driver's module */