[PATCH 4.9 089/101] gadgetfs: ep_io - wait until IRQ finishes

[Greg Kroah-Hartman]

From: Jozef Martiniak <jomajm@xxxxxxxxx>

[ Upstream commit 04cb742d4d8f30dc2e83b46ac317eec09191c68e ]

after usb_ep_queue() if wait_for_completion_interruptible() is
interrupted we need to wait until IRQ gets finished.

Otherwise complete() from epio_complete() can corrupt stack.

Signed-off-by: Jozef Martiniak <jomajm@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220708070645.6130-1-jomajm@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/usb/gadget/legacy/inode.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
index 2b30b5a1b577..8d53b3ac31c6 100644
--- a/drivers/usb/gadget/legacy/inode.c
+++ b/drivers/usb/gadget/legacy/inode.c
@@ -365,6 +365,7 @@ ep_io (struct ep_data *epdata, void *buf, unsigned len)
 				spin_unlock_irq (&epdata->dev->lock);
 
 				DBG (epdata->dev, "endpoint gone\n");
+				wait_for_completion(&done);
 				epdata->status = -ENODEV;
 			}
 		}
-- 
2.35.1