media: em28xx: Don't use ops->suspend if it is NULL

The call to ops->suspend for the dev->dev_next case can currently
trigger a call on a null function pointer if ops->suspend is null.
Skip over the use of function ops->suspend if it is null.

Addresses-Coverity: ("Dereference after null check")

Fixes: be7fd3c3a8c5 ("media: em28xx: Hauppauge DualHD second tuner functionality")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c
index 584fa40..acc0bf7 100644 (file)
--- a/drivers/media/usb/em28xx/em28xx-core.c
+++ b/drivers/media/usb/em28xx/em28xx-core.c
@@ -1154,8 +1154,9 @@ int em28xx_suspend_extension(struct em28xx *dev)
        dev_info(&dev->intf->dev, "Suspending extensions\n");
        mutex_lock(&em28xx_devlist_mutex);
        list_for_each_entry(ops, &em28xx_extension_devlist, next) {
-               if (ops->suspend)
-                       ops->suspend(dev);
+               if (!ops->suspend)
+                       continue;
+               ops->suspend(dev);
                if (dev->dev_next)
                        ops->suspend(dev->dev_next);
        }