From fd901b6e814afcbd54ca65a854f666bd6fe98b8f Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Mon, 23 Apr 2018 07:02:39 -0400 Subject: [PATCH] media: em28xx: Don't use ops->resume if NULL Changeset be7fd3c3a8c5 ("media: em28xx: Hauppauge DualHD second tuner functionality") introduced a potential NULL pointer dereference, as pointed by Coverity: CID 1434731 (#1 of 1): Dereference after null check (FORWARD_NULL)16. var_deref_op: Dereferencing null pointer ops->resume. var_compare_op: Comparing ops->resume to null implies that ops->resume might be null. 1174 if (ops->resume) 1175 ops->resume(dev); 1176 if (dev->dev_next) 1177 ops->resume(dev->dev_next); Fixes: be7fd3c3a8c5 ("media: em28xx: Hauppauge DualHD second tuner functionality") Signed-off-by: Mauro Carvalho Chehab Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- 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 36d341fb65dd..0cefd29184f6 100644 --- a/drivers/media/usb/em28xx/em28xx-core.c +++ b/drivers/media/usb/em28xx/em28xx-core.c @@ -1171,8 +1171,9 @@ int em28xx_resume_extension(struct em28xx *dev) dev_info(&dev->intf->dev, "Resuming extensions\n"); mutex_lock(&em28xx_devlist_mutex); list_for_each_entry(ops, &em28xx_extension_devlist, next) { - if (ops->resume) - ops->resume(dev); + if (!ops->resume) + continue; + ops->resume(dev); if (dev->dev_next) ops->resume(dev->dev_next); } -- 2.11.0