Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Colin King <colin.king@canonical.com>
To:     Mauro Carvalho Chehab <mchehab@kernel.org>,
        Michael Ira Krufky <mkrufky@linuxtv.org>,
        Brad Love <brad@nextdimension.cc>, linux-media@vger.kernel.org
Cc:     kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] media: em28xx: Don't use ops->suspend if it is NULL
Date:   Fri, 17 Sep 2021 17:07:02 +0100
Message-Id: <20210917160702.76961-1-colin.king@canonical.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Colin Ian King <colin.king@canonical.com>

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>
---
 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..92a39fcee206 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);
 	}
-- 
2.32.0