This is a note to let you know that I've just added the patch titled media: em28xx: Don't use ops->suspend if it is NULL to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: media-em28xx-don-t-use-ops-suspend-if-it-is-null.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 44468884cba616ab501e0c26cdb644347b37b620 Author: Colin Ian King <colin.king@xxxxxxxxxxxxx> Date: Fri Sep 17 18:07:02 2021 +0200 media: em28xx: Don't use ops->suspend if it is NULL [ Upstream commit 51fa3b70d27342baf1ea8aaab3e96e5f4f26d5b2 ] 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@xxxxxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c index d0f95a5cb4d23..437651307056f 100644 --- a/drivers/media/usb/em28xx/em28xx-core.c +++ b/drivers/media/usb/em28xx/em28xx-core.c @@ -1151,8 +1151,9 @@ 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); }