From: Alexey Khoroshilov <khoroshilov@ispras.ru>
Date: Thu, 11 Aug 2016 22:05:08 +0000 (+0300)
Subject: USB: serial: mos7720: fix non-atomic allocation in write path
X-Git-Tag: firefly_0821_release~176^2~4^2~31^2~210
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e5d33f1036d4d145495952079e9b023624d0b7c4;p=firefly-linux-kernel-4.4.55.git

USB: serial: mos7720: fix non-atomic allocation in write path

commit 5a5a1d614287a647b36dff3f40c2b0ceabbc83ec upstream.

There is an allocation with GFP_KERNEL flag in mos7720_write(),
while it may be called from interrupt context.

Follow-up for commit 191252837626 ("USB: kobil_sct: fix non-atomic
allocation in write path")

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/serial/mos7720.c b/drivers/usb/serial/mos7720.c
index 06c7dbc1c802..63db004af21f 100644
--- a/drivers/usb/serial/mos7720.c
+++ b/drivers/usb/serial/mos7720.c
@@ -1252,7 +1252,7 @@ static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
 
 	if (urb->transfer_buffer == NULL) {
 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
-					       GFP_KERNEL);
+					       GFP_ATOMIC);
 		if (!urb->transfer_buffer)
 			goto exit;
 	}