[PATCH v4 00/19] media: Fix locking issues in rc core

[PATCH v4 00/19] media: Fix locking issues in rc core

[Sean Young]

Fix issues found by Sashiko and claude, and other cleanups.

Changes since v3:
 - serial_ir: Fix race condition where timer can be re-armed
   This introduced a new race condition; reworked
 - rc: After rc_unregister_device() timers can be re-armed
   Sashiko suggested a simpler implementation with
   timer_shutdown_sync()
 - Add meson-ir-tx: Validate carrier and duty_cycle
 - Add ir_toy: Validate the maximum tx carrier

Changes since v2:
 - Cosmetic changes in:  Add missing locking for keymap
 - Patch 7 to 17 are new issues found

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 (19):
  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
  media: ene_ir: Ensure teardown is done in the correct order
  media: rc: Use binary search for adding or updating a scancode
  media: rc: imon: Bind both interfaces via usb_driver_claim_interface()
  media: ir_toy: Remove unused struct field
  media: nuvoton-cir: Remove unused struct field
  media: ite-cir: Removed unused struct field
  media: fintek-cir: Remove unused fields
  media: mceusb: Remove unused field
  media: serial_ir: Fix race condition where timer can be re-armed
  media: rc: After rc_unregister_device() timers can be re-armed
  media: rc: Validate carrier range in LIRC_SET_REC_CARRIER ioctl
  media: ir_toy: Validate the maximum tx carrier
  media: meson-ir-tx: Validate carrier and duty_cycle

 drivers/media/rc/ene_ir.c             |   4 +-
 drivers/media/rc/fintek-cir.c         |  13 --
 drivers/media/rc/fintek-cir.h         |  22 ----
 drivers/media/rc/imon.c               | 166 +++++++++++--------------
 drivers/media/rc/ir-mce_kbd-decoder.c |   5 +-
 drivers/media/rc/ir_toy.c             |   4 +-
 drivers/media/rc/ite-cir.c            |   1 -
 drivers/media/rc/ite-cir.h            |   1 -
 drivers/media/rc/lirc_dev.c           |   2 +
 drivers/media/rc/mceusb.c             |   1 -
 drivers/media/rc/meson-ir-tx.c        |  54 ++++++--
 drivers/media/rc/nuvoton-cir.h        |   3 -
 drivers/media/rc/rc-ir-raw.c          |  39 +++---
 drivers/media/rc/rc-loopback.c        |   5 -
 drivers/media/rc/rc-main.c            | 169 ++++++++++++++++----------
 drivers/media/rc/serial_ir.c          |   2 +-
 include/media/rc-map.h                |   2 -
 17 files changed, 251 insertions(+), 242 deletions(-)

-- 
2.55.0

[PATCH v4 05/19] 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 04204559959f..924b13fff753 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