[PATCH 3.10 113/319] USB: serial: mos7840: fix non-atomic allocation in write path

Willy Tarreau
2017-02-05T19:23:57Z

From: Alexey Khoroshilov <khoroshilov@ispras.ru>

commit 3b7c7e52efda0d4640060de747768360ba70a7c0 upstream.

There is an allocation with GFP_KERNEL flag in mos7840_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: Willy Tarreau <w@1wt.eu>
---
drivers/usb/serial/mos7840.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index d060130..7df7df6 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -1438,8 +1438,8 @@ static int mos7840_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);
+ urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
+ GFP_ATOMIC);

if (urb->transfer_buffer == NULL) {
dev_err_console(port, "%s no more kernel memory...\n",
--
2.8.0.rc2.1.gbe9624a