[PATCH] usb: usbtest: Convert timers to use timer_setup()

From: Kees Cook
Date: Tue Oct 24 2017 - 06:11:12 EST


In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Also adds missing call to
destroy_timer_on_stack();

Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Cc: "Gustavo A. R. Silva" <garsilva@xxxxxxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/usb/misc/usbtest.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
index 3639e00a51a0..7f61921e4fa0 100644
--- a/drivers/usb/misc/usbtest.c
+++ b/drivers/usb/misc/usbtest.c
@@ -576,11 +576,16 @@ alloc_sglist(int nents, int max, int vary, struct usbtest_dev *dev, int pipe)
return sg;
}

-static void sg_timeout(unsigned long _req)
+struct sg_timeout {
+ struct timer_list timer;
+ struct usb_sg_request *req;
+};
+
+static void sg_timeout(struct timer_list *t)
{
- struct usb_sg_request *req = (struct usb_sg_request *) _req;
+ struct sg_timeout *timeout = from_timer(timeout, t, timer);

- usb_sg_cancel(req);
+ usb_sg_cancel(timeout->req);
}

static int perform_sglist(
@@ -594,9 +599,11 @@ static int perform_sglist(
{
struct usb_device *udev = testdev_to_usbdev(tdev);
int retval = 0;
- struct timer_list sg_timer;
+ struct sg_timeout timeout = {
+ .req = req,
+ };

- setup_timer_on_stack(&sg_timer, sg_timeout, (unsigned long) req);
+ timer_setup_on_stack(&timeout.timer, sg_timeout, 0);

while (retval == 0 && iterations-- > 0) {
retval = usb_sg_init(req, udev, pipe,
@@ -607,13 +614,14 @@ static int perform_sglist(

if (retval)
break;
- mod_timer(&sg_timer, jiffies +
+ mod_timer(&timeout.timer, jiffies +
msecs_to_jiffies(SIMPLE_IO_TIMEOUT));
usb_sg_wait(req);
- if (!del_timer_sync(&sg_timer))
+ if (!del_timer_sync(&timeout.timer))
retval = -ETIMEDOUT;
else
retval = req->status;
+ destroy_timer_on_stack(&timeout.timer);

/* FIXME check resulting data pattern */

--
2.7.4


--
Kees Cook
Pixel Security