From: Colin Ian King <colin.king@canonical.com>
Date: Fri, 17 Sep 2021 16:07:02 +0000 (+0200)
Subject: media: em28xx: Don't use ops->suspend if it is NULL
X-Git-Tag: v6.6.17~8751^2~92
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=51fa3b70d27342baf1ea8aaab3e96e5f4f26d5b2;p=platform%2Fkernel%2Flinux-rpi.git

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
--- 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);
 	}