From 51fa3b70d27342baf1ea8aaab3e96e5f4f26d5b2 Mon Sep 17 00:00:00 2001
From: Colin Ian King <colin.king@canonical.com>
Date: Fri, 17 Sep 2021 18:07:02 +0200
Subject: [PATCH] media: em28xx: Don't use ops->suspend if it is NULL
Git-commit: 51fa3b70d27342baf1ea8aaab3e96e5f4f26d5b2
Patch-mainline: v5.16-rc1
References: git-fixes

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>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/media/usb/em28xx/em28xx-core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c
index 584fa400cd7d..acc0bf7dbe2b 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);
 	}
-- 
2.26.2