From: Jia-Ju Bai Date: Wed, 20 Jun 2018 03:55:08 +0000 (+0800) Subject: usb: gadget: r8a66597: Fix a possible sleep-in-atomic-context bugs in r8a66597_queue() X-Git-Tag: v4.18-rc7~15^2~4^2~16 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f36b507c14c4b6e634463a610294e9cb0065c8ea;p=thirdparty%2Flinux.git usb: gadget: r8a66597: Fix a possible sleep-in-atomic-context bugs in r8a66597_queue() 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 Signed-off-by: Felipe Balbi --- diff --git a/drivers/usb/gadget/udc/r8a66597-udc.c b/drivers/usb/gadget/udc/r8a66597-udc.c index 24ee9867964b1..11e25a3f4f1fa 100644 --- a/drivers/usb/gadget/udc/r8a66597-udc.c +++ b/drivers/usb/gadget/udc/r8a66597-udc.c @@ -1190,7 +1190,7 @@ __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); }