4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> [ Upstream commit f36b507c14c4b6e634463a610294e9cb0065c8ea ] The driver may sleep in an interrupt handler. The function call path (from bottom to top) in Linux-4.16.7 is: [FUNC] r8a66597_queue(GFP_KERNEL) drivers/usb/gadget/udc/r8a66597-udc.c, 1193: r8a66597_queue in get_status drivers/usb/gadget/udc/r8a66597-udc.c, 1301: get_status in setup_packet drivers/usb/gadget/udc/r8a66597-udc.c, 1381: setup_packet in irq_control_stage drivers/usb/gadget/udc/r8a66597-udc.c, 1508: irq_control_stage in r8a66597_irq (interrupt handler) To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC. This bug is found by my static analysis tool (DSAC-2) and checked by my code review. Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/gadget/udc/r8a66597-udc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/gadget/udc/r8a66597-udc.c +++ b/drivers/usb/gadget/udc/r8a66597-udc.c @@ -1193,7 +1193,7 @@ __acquires(r8a66597->lock) r8a66597->ep0_req->length = 2; /* AV: what happens if we get called again before that gets through? */ spin_unlock(&r8a66597->lock); - r8a66597_queue(r8a66597->gadget.ep0, r8a66597->ep0_req, GFP_KERNEL); + r8a66597_queue(r8a66597->gadget.ep0, r8a66597->ep0_req, GFP_ATOMIC); spin_lock(&r8a66597->lock); }
