From a2e2d73fa28136598e84db9d021091f1b98cbb1a Mon Sep 17 00:00:00 2001 From: Sean Young Date: Sat, 8 Aug 2020 13:38:02 +0200 Subject: media: rc: do not access device via sysfs after rc_unregister_device() Device drivers do not expect to have change_protocol or wakeup re-programming to be accesed after rc_unregister_device(). This can cause the device driver to access deallocated resources. Cc: # 4.16+ Signed-off-by: Sean Young Signed-off-by: Mauro Carvalho Chehab --- drivers/media/rc/rc-main.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/media') diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c index e1cda80a4b25..dee8a9f3d80a 100644 --- a/drivers/media/rc/rc-main.c +++ b/drivers/media/rc/rc-main.c @@ -1292,6 +1292,10 @@ static ssize_t store_protocols(struct device *device, } mutex_lock(&dev->lock); + if (!dev->registered) { + mutex_unlock(&dev->lock); + return -ENODEV; + } old_protocols = *current_protocols; new_protocols = old_protocols; @@ -1430,6 +1434,10 @@ static ssize_t store_filter(struct device *device, return -EINVAL; mutex_lock(&dev->lock); + if (!dev->registered) { + mutex_unlock(&dev->lock); + return -ENODEV; + } new_filter = *filter; if (fattr->mask) @@ -1544,6 +1552,10 @@ static ssize_t store_wakeup_protocols(struct device *device, int i; mutex_lock(&dev->lock); + if (!dev->registered) { + mutex_unlock(&dev->lock); + return -ENODEV; + } allowed = dev->allowed_wakeup_protocols; -- cgit