[PATCH 5.4 089/165] rfkill: Fix incorrect check to avoid NULL pointer dereference

Greg Kroah-Hartman
2020-01-11T10:28:29Z

From: Aditya Pakki <pakki001@umn.edu>

[ Upstream commit 6fc232db9e8cd50b9b83534de9cd91ace711b2d7 ]

In rfkill_register, the struct rfkill pointer is first derefernced
and then checked for NULL. This patch removes the BUG_ON and returns
an error to the caller in case rfkill is NULL.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Link: https://lore.kernel.org/r/20191215153409.21696-1-pakki001@umn.edu
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/rfkill/core.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/rfkill/core.c b/net/rfkill/core.c
index 0bf9bf1ceb8f..6c089320ae4f 100644
--- a/net/rfkill/core.c
+++ b/net/rfkill/core.c
@@ -1002,10 +1002,13 @@ static void rfkill_sync_work(struct work_struct *work)
int __must_check rfkill_register(struct rfkill *rfkill)
{
static unsigned long rfkill_no;
- struct device *dev = &rfkill->dev;
+ struct device *dev;
int error;

- BUG_ON(!rfkill);
+ if (!rfkill)
+ return -EINVAL;
+
+ dev = &rfkill->dev;

mutex_lock(&rfkill_global_mutex);

--
2.20.1