From: Phil Elwell phil@raspberrypi.com
[ Upstream commit 96ae327678eceabf455b11a88ba14ad540d4b046 ]
The addition of the local 'userdata' pointer to vchiq_irq_queue_bulk_tx_rx omitted the case where neither BLOCKING nor WAITING modes are used, in which case the value provided by the caller is not returned to them as expected, but instead it is replaced with a NULL. This lack of a suitable context may cause the application to crash or otherwise malfunction.
Fixes: 4184da4f316a ("staging: vchiq: fix __user annotations") Tested-by: Stefan Wahren stefan.wahren@i2se.com Acked-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Phil Elwell phil@raspberrypi.com Link: https://lore.kernel.org/r/20210105162030.1415213-2-phil@raspberrypi.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c index f500a70438056..2a8883673ba11 100644 --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c @@ -958,7 +958,7 @@ static int vchiq_irq_queue_bulk_tx_rx(struct vchiq_instance *instance, struct vchiq_service *service; struct bulk_waiter_node *waiter = NULL; bool found = false; - void *userdata = NULL; + void *userdata; int status = 0; int ret;
@@ -997,6 +997,8 @@ static int vchiq_irq_queue_bulk_tx_rx(struct vchiq_instance *instance, "found bulk_waiter %pK for pid %d", waiter, current->pid); userdata = &waiter->bulk_waiter; + } else { + userdata = args->userdata; }
/*