[PATCH AUTOSEL 4.4 21/28] HID: hiddev: do cleanup in failure of opening a device

From: Sasha Levin
Date: Tue Aug 13 2019 - 22:27:05 EST


From: Hillf Danton <hdanton@xxxxxxxx>

[ Upstream commit 6d4472d7bec39917b54e4e80245784ea5d60ce49 ]

Undo what we did for opening before releasing the memory slice.

Reported-by: syzbot <syzbot+62a1e04fd3ec2abf099e@xxxxxxxxxxxxxxxxxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Signed-off-by: Hillf Danton <hdanton@xxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hid/usbhid/hiddev.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 0bfc2009e4071..8903ea09ac587 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c
@@ -330,6 +330,10 @@ static int hiddev_open(struct inode *inode, struct file *file)
return 0;
bail_unlock:
mutex_unlock(&hiddev->existancelock);
+
+ spin_lock_irq(&list->hiddev->list_lock);
+ list_del(&list->node);
+ spin_unlock_irq(&list->hiddev->list_lock);
bail:
file->private_data = NULL;
vfree(list);
--
2.20.1