Hi Dan, Thanks for your report. A proposed fix to this is available [1], awaiting inclusion in the media-tree :-)
1. https://patchwork.linuxtv.org/patch/49025/ On 2018-05-03 15:36:30 +0300, Dan Carpenter wrote: > Hello Niklas Söderlund, > > The patch 3bb4c3bc85bf: "media: rcar-vin: add group allocator > functions" from Apr 14, 2018, leads to the following static checker > warning: > > drivers/media/platform/rcar-vin/rcar-core.c:346 rvin_group_put() > error: potential NULL dereference 'vin->group'. > > drivers/media/platform/rcar-vin/rcar-core.c > 339 static void rvin_group_put(struct rvin_dev *vin) > 340 { > 341 mutex_lock(&vin->group->lock); > 342 > 343 vin->group = NULL; > ^^^^^^^^^^^^^^^^^ > Set to NULL. > > 344 vin->v4l2_dev.mdev = NULL; > 345 > 346 if (WARN_ON(vin->group->vin[vin->id] != vin)) > ^^^^^^^^^^^^^^^^^^^^^^^^ > 347 goto out; > 348 > 349 vin->group->vin[vin->id] = NULL; > ^^^^^^^^^^^^^^^^^^^^^^^^ > 350 out: > 351 mutex_unlock(&vin->group->lock); > ^^^^^^^^^^^^^^^^ > 352 > 353 kref_put(&vin->group->refcount, rvin_group_release); > ^^^^^^^^^^^^^^^^^^^^ > > There are a bunch of NULL dereferences here... > > 354 } > > regards, > dan carpenter -- Regards, Niklas Söderlund
