[PATCH 3.2 068/152] USB: serial: mos7720: fix non-atomic allocation in write path

From: Ben Hutchings
Date: Sun Nov 13 2016 - 21:12:53 EST


3.2.84-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/usb/serial/mos7720.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/serial/mos7720.c
+++ b/drivers/usb/serial/mos7720.c
@@ -1320,7 +1320,7 @@ static int mos7720_write(struct tty_stru

if (urb->transfer_buffer == NULL) {
urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
- GFP_KERNEL);
+ GFP_ATOMIC);
if (urb->transfer_buffer == NULL) {
dev_err(&port->dev, "%s no more kernel memory...\n",
__func__);