[PATCH 5.4 81/92] can: ucan: fix non-atomic allocation in completion handler

From: Greg Kroah-Hartman
Date: Wed Dec 11 2019 - 10:11:06 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit 870db5d1015c8bd63e93b579e857223c96249ff7 upstream.

USB completion handlers are called in atomic context and must
specifically not allocate memory using GFP_KERNEL.

Fixes: 9f2d3eae88d2 ("can: ucan: add driver for Theobroma Systems UCAN devices")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.19
Cc: Jakob Unterwurzacher <jakob.unterwurzacher@xxxxxxxxxxxxxxxxxxxxx>
Cc: Martin Elshuber <martin.elshuber@xxxxxxxxxxxxxxxxxxxxx>
Cc: Philipp Tomsich <philipp.tomsich@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/can/usb/ucan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/can/usb/ucan.c
+++ b/drivers/net/can/usb/ucan.c
@@ -792,7 +792,7 @@ resubmit:
up);

usb_anchor_urb(urb, &up->rx_urbs);
- ret = usb_submit_urb(urb, GFP_KERNEL);
+ ret = usb_submit_urb(urb, GFP_ATOMIC);

if (ret < 0) {
netdev_err(up->netdev,