From: Sean Young sean@mess.org
commit 080d89f522e2baddb4fbbd1af4b67b5f92537ef8 upstream.
Once rc_open is called on the input device, lirc events can be delivered. Ensure lirc is ready to do so else we might get this:
Registered IR keymap rc-hauppauge rc rc0: Hauppauge WinTV PVR-350 as /devices/pci0000:00/0000:00:1e.0/0000:04:00.0/i2c-0/0-0018/rc/rc0 input: Hauppauge WinTV PVR-350 as /devices/pci0000:00/0000:00:1e.0/0000:04:00.0/i2c-0/0-0018/rc/rc0/input9 BUG: kernel NULL pointer dereference, address: 0000000000000038 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.3.11-300.fc31.x86_64 #1 Hardware name: /DG43NB, BIOS NBG4310H.86A.0096.2009.0903.1845 09/03/2009 Workqueue: events ir_work [ir_kbd_i2c] RIP: 0010:ir_lirc_scancode_event+0x3d/0xb0 Code: a6 b4 07 00 00 49 81 c6 b8 07 00 00 55 53 e8 ba a7 9d ff 4c 89 e7 49 89 45 00 e8 5e 7a 25 00 49 8b 1e 48 89 c5 4c 39 f3 74 58 <8b> 43 38 8b 53 40 89 c1 2b 4b 3c 39 ca 72 41 21 d0 49 8b 7d 00 49 RSP: 0018:ffffaae2000b3d88 EFLAGS: 00010017 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000000000019 RDX: 0000000000000001 RSI: 006e801b1f26ce6a RDI: ffff9e39797c37b4 RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000001 R12: ffff9e39797c37b4 R13: ffffaae2000b3db8 R14: ffff9e39797c37b8 R15: ffff9e39797c33d8 FS: 0000000000000000(0000) GS:ffff9e397b680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 0000000035844000 CR4: 00000000000006e0 Call Trace: ir_do_keydown+0x8e/0x2b0 rc_keydown+0x52/0xc0 ir_work+0xb8/0x130 [ir_kbd_i2c] process_one_work+0x19d/0x340 worker_thread+0x50/0x3b0 kthread+0xfb/0x130 ? process_one_work+0x340/0x340 ? kthread_park+0x80/0x80 ret_from_fork+0x35/0x40 Modules linked in: rc_hauppauge tuner msp3400 saa7127 saa7115 ivtv(+) tveeprom cx2341x v4l2_common videodev mc i2c_algo_bit ir_kbd_i2c ip_tables firewire_ohci e1000e serio_raw firewire_core ata_generic crc_itu_t pata_acpi pata_jmicron fuse CR2: 0000000000000038 ---[ end trace c67c2697a99fa74b ]--- RIP: 0010:ir_lirc_scancode_event+0x3d/0xb0 Code: a6 b4 07 00 00 49 81 c6 b8 07 00 00 55 53 e8 ba a7 9d ff 4c 89 e7 49 89 45 00 e8 5e 7a 25 00 49 8b 1e 48 89 c5 4c 39 f3 74 58 <8b> 43 38 8b 53 40 89 c1 2b 4b 3c 39 ca 72 41 21 d0 49 8b 7d 00 49 RSP: 0018:ffffaae2000b3d88 EFLAGS: 00010017 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000000000019 RDX: 0000000000000001 RSI: 006e801b1f26ce6a RDI: ffff9e39797c37b4 RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000001 R12: ffff9e39797c37b4 R13: ffffaae2000b3db8 R14: ffff9e39797c37b8 R15: ffff9e39797c33d8 FS: 0000000000000000(0000) GS:ffff9e397b680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 0000000035844000 CR4: 00000000000006e0 rc rc0: lirc_dev: driver ir_kbd_i2c registered at minor = 0, scancode receiver, no transmitter tuner-simple 0-0061: creating new instance tuner-simple 0-0061: type set to 2 (Philips NTSC (FI1236,FM1236 and compatibles)) ivtv0: Registered device video0 for encoder MPG (4096 kB) ivtv0: Registered device video32 for encoder YUV (2048 kB) ivtv0: Registered device vbi0 for encoder VBI (1024 kB) ivtv0: Registered device video24 for encoder PCM (320 kB) ivtv0: Registered device radio0 for encoder radio ivtv0: Registered device video16 for decoder MPG (1024 kB) ivtv0: Registered device vbi8 for decoder VBI (64 kB) ivtv0: Registered device vbi16 for decoder VOUT ivtv0: Registered device video48 for decoder YUV (1024 kB)
Cc: stable@vger.kernel.org Tested-by: Nick French nickfrench@gmail.com Reported-by: Nick French nickfrench@gmail.com Signed-off-by: Sean Young sean@mess.org Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/media/rc/rc-main.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-)
diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c index 0f218af..c30affb 100644 --- a/drivers/media/rc/rc-main.c +++ b/drivers/media/rc/rc-main.c @@ -1874,23 +1874,28 @@ int rc_register_device(struct rc_dev *dev)
dev->registered = true;
- if (dev->driver_type != RC_DRIVER_IR_RAW_TX) { - rc = rc_setup_rx_device(dev); - if (rc) - goto out_dev; - } - - /* Ensure that the lirc kfifo is setup before we start the thread */ + /* + * once the the input device is registered in rc_setup_rx_device, + * userspace can open the input device and rc_open() will be called + * as a result. This results in driver code being allowed to submit + * keycodes with rc_keydown, so lirc must be registered first. + */ if (dev->allowed_protocols != RC_PROTO_BIT_CEC) { rc = ir_lirc_register(dev); if (rc < 0) - goto out_rx; + goto out_dev; + } + + if (dev->driver_type != RC_DRIVER_IR_RAW_TX) { + rc = rc_setup_rx_device(dev); + if (rc) + goto out_lirc; }
if (dev->driver_type == RC_DRIVER_IR_RAW) { rc = ir_raw_event_register(dev); if (rc < 0) - goto out_lirc; + goto out_rx; }
dev_dbg(&dev->dev, "Registered rc%u (driver: %s)\n", dev->minor, @@ -1898,11 +1903,11 @@ int rc_register_device(struct rc_dev *dev)
return 0;
+out_rx: + rc_free_rx_device(dev); out_lirc: if (dev->allowed_protocols != RC_PROTO_BIT_CEC) ir_lirc_unregister(dev); -out_rx: - rc_free_rx_device(dev); out_dev: device_del(&dev->dev); out_rx_free: