[PATCH v2 0/6] Fix locking issues in rc core

[PATCH v2 0/6] Fix locking issues in rc core

[Sean Young]

Changes since v1:
 - Fix issue where input device was still leaked
 - Add: Fix race between bpf(BPG_PROG_ATTACH) and device unregister
 - Add: Fix inconsistent locking of keylock

Sean Young (6):
  media: rc: Ensure registered is cleared in error path
  media: rc: Ensure that rc_unregister_device() does not free input
    device
  media: rc: Fix ABBA deadlock by making locks more fine grained
  media: rc: Add missing locking for keymap
  media: rc: Fix race between bpf(BPG_PROG_ATTACH) and device unregister
  media: rc: mce_kbd: Fix inconsistent locking of keylock

 drivers/media/rc/ir-mce_kbd-decoder.c |   5 +-
 drivers/media/rc/rc-ir-raw.c          |  39 ++++---
 drivers/media/rc/rc-main.c            | 147 +++++++++++++++-----------
 include/media/rc-map.h                |   2 -
 4 files changed, 115 insertions(+), 78 deletions(-)

-- 
2.55.0

[PATCH v2 5/6] media: rc: Fix race between bpf(BPG_PROG_ATTACH) and device unregister

[Sean Young]

Mark the device as unregistered before tearing down raw IR/bpf
state, so that racing bpf(BPF_PROG_{ATTACH,DETACH,QUERY}) calls
cannot slip in between ir_raw_event_unregister() completing and
dev->registered being cleared.

Fixes: dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks")
Signed-off-by: Sean Young <sean@mess.org>
Cc: stable@vger.kernel.org
---
 drivers/media/rc/rc-main.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
index 3091bcd0e927..af7888fbfb91 100644
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -2050,18 +2050,18 @@ void rc_unregister_device(struct rc_dev *dev)
 	if (!dev)
 		return;
 
+	mutex_lock(&dev->lock);
+	dev->registered = false;
+	if (dev->users && dev->close)
+		dev->close(dev);
+	mutex_unlock(&dev->lock);
+
 	if (dev->driver_type == RC_DRIVER_IR_RAW)
 		ir_raw_event_unregister(dev);
 
 	timer_delete_sync(&dev->timer_keyup);
 	timer_delete_sync(&dev->timer_repeat);
 
-	mutex_lock(&dev->lock);
-	if (dev->users && dev->close)
-		dev->close(dev);
-	dev->registered = false;
-	mutex_unlock(&dev->lock);
-
 	rc_free_rx_device(dev);
 
 	/*
-- 
2.55.0