4.4-stable review patch. If anyone has any objections, please let me know.
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From: Stephen Warren swarren@nvidia.com
commit daa35bd95634a2a2d72d1049c93576a02711cb1a upstream.
When the gadget serial device has no associated TTY, do not pass any received data into the TTY layer for processing; simply drop it instead. This prevents the TTY layer from calling back into the gadget serial driver, which will then crash in e.g. gs_write_room() due to lack of gadget serial device to TTY association (i.e. a NULL pointer dereference).
Signed-off-by: Stephen Warren swarren@nvidia.com Signed-off-by: Felipe Balbi felipe.balbi@linux.intel.com Signed-off-by: Krzysztof Kozlowski krzk@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/usb/gadget/function/u_serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -518,7 +518,7 @@ static void gs_rx_push(unsigned long _po }
/* push data to (open) tty */ - if (req->actual) { + if (req->actual && tty) { char *packet = req->buf; unsigned size = req->actual; unsigned n;