diff mbox series

HID: logitech-hidpp: Fix kernel crash on receiver USB disconnect

Message ID 20231005182638.3776-1-hdegoede@redhat.com
State Accepted
Commit dac501397b9d81e4782232c39f94f4307b137452
Headers show
Series HID: logitech-hidpp: Fix kernel crash on receiver USB disconnect | expand

Commit Message

Hans de Goede Oct. 5, 2023, 6:26 p.m. UTC
hidpp_connect_event() has *four* time-of-check vs time-of-use (TOCTOU)
races when it races with itself.

hidpp_connect_event() primarily runs from a workqueue but it also runs
on probe() and if a "device-connected" packet is received by the hw
when the thread running hidpp_connect_event() from probe() is waiting on
the hw, then a second thread running hidpp_connect_event() will be
started from the workqueue.

This opens the following races (note the below code is simplified):

1. Retrieving + printing the protocol (harmless race):

	if (!hidpp->protocol_major) {
		hidpp_root_get_protocol_version()
		hidpp->protocol_major = response.rap.params[0];
	}

We can actually see this race hit in the dmesg in the abrt output
attached to rhbz#2227968:

[ 3064.624215] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
[ 3064.658184] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.

Testing with extra logging added has shown that after this the 2 threads
take turn grabbing the hw access mutex (send_mutex) so they ping-pong
through all the other TOCTOU cases managing to hit all of them:

2. Updating the name to the HIDPP name (harmless race):

	if (hidpp->name == hdev->name) {
		...
		hidpp->name = new_name;
	}

3. Initializing the power_supply class for the battery (problematic!):

hidpp_initialize_battery()
{
        if (hidpp->battery.ps)
                return 0;

	probe_battery(); /* Blocks, threads take turns executing this */

	hidpp->battery.desc.properties =
		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);

	hidpp->battery.ps =
		devm_power_supply_register(&hidpp->hid_dev->dev,
					   &hidpp->battery.desc, cfg);
}

4. Creating delayed input_device (potentially problematic):

	if (hidpp->delayed_input)
		return;

	hidpp->delayed_input = hidpp_allocate_input(hdev);

The really big problem here is 3. Hitting the race leads to the following
sequence:

	hidpp->battery.desc.properties =
		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);

	hidpp->battery.ps =
		devm_power_supply_register(&hidpp->hid_dev->dev,
					   &hidpp->battery.desc, cfg);

	...

	hidpp->battery.desc.properties =
		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);

	hidpp->battery.ps =
		devm_power_supply_register(&hidpp->hid_dev->dev,
					   &hidpp->battery.desc, cfg);

So now we have registered 2 power supplies for the same battery,
which looks a bit weird from userspace's pov but this is not even
the really big problem.

Notice how:

1. This is all devm-maganaged
2. The hidpp->battery.desc struct is shared between the 2 power supplies
3. hidpp->battery.desc points to the result from the second devm_kmemdup()

This causes a use after free scenario on USB disconnect of the receiver:
1. The last registered power supply class device gets unregistered
2. The memory from the last devm_kmemdup() call gets freed,
   hidpp->battery.desc.properties now points to freed memory
3. The first registered power supply class device gets unregistered,
   this involves sending a remove uevent to userspace which invokes
   power_supply_uevent() to fill the uevent data
4. power_supply_uevent() uses hidpp->battery.desc.properties which
   now points to freed memory leading to backtraces like this one:

Sep 22 20:01:35 eric kernel: BUG: unable to handle page fault for address: ffffb2140e017f08
...
Sep 22 20:01:35 eric kernel: Workqueue: usb_hub_wq hub_event
Sep 22 20:01:35 eric kernel: RIP: 0010:power_supply_uevent+0xee/0x1d0
...
Sep 22 20:01:35 eric kernel:  ? asm_exc_page_fault+0x26/0x30
Sep 22 20:01:35 eric kernel:  ? power_supply_uevent+0xee/0x1d0
Sep 22 20:01:35 eric kernel:  ? power_supply_uevent+0x10d/0x1d0
Sep 22 20:01:35 eric kernel:  dev_uevent+0x10f/0x2d0
Sep 22 20:01:35 eric kernel:  kobject_uevent_env+0x291/0x680
Sep 22 20:01:35 eric kernel:  power_supply_unregister+0x8e/0xa0
Sep 22 20:01:35 eric kernel:  release_nodes+0x3d/0xb0
Sep 22 20:01:35 eric kernel:  devres_release_group+0xfc/0x130
Sep 22 20:01:35 eric kernel:  hid_device_remove+0x56/0xa0
Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
Sep 22 20:01:35 eric kernel:  ? __queue_work+0x1df/0x440
Sep 22 20:01:35 eric kernel:  hid_destroy_device+0x4b/0x60
Sep 22 20:01:35 eric kernel:  logi_dj_remove+0x9a/0x100 [hid_logitech_dj 5c91534a0ead2b65e04dd799a0437e3b99b21bc4]
Sep 22 20:01:35 eric kernel:  hid_device_remove+0x44/0xa0
Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
Sep 22 20:01:35 eric kernel:  ? __queue_work+0x1df/0x440
Sep 22 20:01:35 eric kernel:  hid_destroy_device+0x4b/0x60
Sep 22 20:01:35 eric kernel:  usbhid_disconnect+0x47/0x60 [usbhid 727dcc1c0b94e6b4418727a468398ac3bca492f3]
Sep 22 20:01:35 eric kernel:  usb_unbind_interface+0x90/0x270
Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
Sep 22 20:01:35 eric kernel:  ? kobject_put+0xa0/0x1d0
Sep 22 20:01:35 eric kernel:  usb_disable_device+0xcd/0x1e0
Sep 22 20:01:35 eric kernel:  usb_disconnect+0xde/0x2c0
Sep 22 20:01:35 eric kernel:  usb_disconnect+0xc3/0x2c0
Sep 22 20:01:35 eric kernel:  hub_event+0xe80/0x1c10

There have been quite a few bug reports (see Link tags) about this crash.

Fix all the TOCTOU issues, including the really bad power-supply related
system crash on USB disconnect, by making probe() use the workqueue for
running hidpp_connect_event() too, so that it can never run more then once.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227221
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227968
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227968
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2242189
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217412#c58
Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/hid/hid-logitech-hidpp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Hans de Goede Oct. 6, 2023, 7:59 a.m. UTC | #1
Hi Benjamin,

On 10/6/23 09:29, Benjamin Tissoires wrote:
> Hi Hans,
> 
> On Oct 05 2023, Hans de Goede wrote:
>> hidpp_connect_event() has *four* time-of-check vs time-of-use (TOCTOU)
>> races when it races with itself.
>>
>> hidpp_connect_event() primarily runs from a workqueue but it also runs
>> on probe() and if a "device-connected" packet is received by the hw
>> when the thread running hidpp_connect_event() from probe() is waiting on
>> the hw, then a second thread running hidpp_connect_event() will be
>> started from the workqueue.
>>
>> This opens the following races (note the below code is simplified):
>>
>> 1. Retrieving + printing the protocol (harmless race):
>>
>> 	if (!hidpp->protocol_major) {
>> 		hidpp_root_get_protocol_version()
>> 		hidpp->protocol_major = response.rap.params[0];
>> 	}
>>
>> We can actually see this race hit in the dmesg in the abrt output
>> attached to rhbz#2227968:
>>
>> [ 3064.624215] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
>> [ 3064.658184] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
>>
>> Testing with extra logging added has shown that after this the 2 threads
>> take turn grabbing the hw access mutex (send_mutex) so they ping-pong
>> through all the other TOCTOU cases managing to hit all of them:
>>
>> 2. Updating the name to the HIDPP name (harmless race):
>>
>> 	if (hidpp->name == hdev->name) {
>> 		...
>> 		hidpp->name = new_name;
>> 	}
>>
>> 3. Initializing the power_supply class for the battery (problematic!):
>>
>> hidpp_initialize_battery()
>> {
>>         if (hidpp->battery.ps)
>>                 return 0;
>>
>> 	probe_battery(); /* Blocks, threads take turns executing this */
>>
>> 	hidpp->battery.desc.properties =
>> 		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
>>
>> 	hidpp->battery.ps =
>> 		devm_power_supply_register(&hidpp->hid_dev->dev,
>> 					   &hidpp->battery.desc, cfg);
>> }
>>
>> 4. Creating delayed input_device (potentially problematic):
>>
>> 	if (hidpp->delayed_input)
>> 		return;
>>
>> 	hidpp->delayed_input = hidpp_allocate_input(hdev);
>>
>> The really big problem here is 3. Hitting the race leads to the following
>> sequence:
>>
>> 	hidpp->battery.desc.properties =
>> 		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
>>
>> 	hidpp->battery.ps =
>> 		devm_power_supply_register(&hidpp->hid_dev->dev,
>> 					   &hidpp->battery.desc, cfg);
>>
>> 	...
>>
>> 	hidpp->battery.desc.properties =
>> 		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
>>
>> 	hidpp->battery.ps =
>> 		devm_power_supply_register(&hidpp->hid_dev->dev,
>> 					   &hidpp->battery.desc, cfg);
>>
>> So now we have registered 2 power supplies for the same battery,
>> which looks a bit weird from userspace's pov but this is not even
>> the really big problem.
>>
>> Notice how:
>>
>> 1. This is all devm-maganaged
>> 2. The hidpp->battery.desc struct is shared between the 2 power supplies
>> 3. hidpp->battery.desc points to the result from the second devm_kmemdup()
>>
>> This causes a use after free scenario on USB disconnect of the receiver:
>> 1. The last registered power supply class device gets unregistered
>> 2. The memory from the last devm_kmemdup() call gets freed,
>>    hidpp->battery.desc.properties now points to freed memory
>> 3. The first registered power supply class device gets unregistered,
>>    this involves sending a remove uevent to userspace which invokes
>>    power_supply_uevent() to fill the uevent data
>> 4. power_supply_uevent() uses hidpp->battery.desc.properties which
>>    now points to freed memory leading to backtraces like this one:
>>
>> Sep 22 20:01:35 eric kernel: BUG: unable to handle page fault for address: ffffb2140e017f08
>> ...
>> Sep 22 20:01:35 eric kernel: Workqueue: usb_hub_wq hub_event
>> Sep 22 20:01:35 eric kernel: RIP: 0010:power_supply_uevent+0xee/0x1d0
>> ...
>> Sep 22 20:01:35 eric kernel:  ? asm_exc_page_fault+0x26/0x30
>> Sep 22 20:01:35 eric kernel:  ? power_supply_uevent+0xee/0x1d0
>> Sep 22 20:01:35 eric kernel:  ? power_supply_uevent+0x10d/0x1d0
>> Sep 22 20:01:35 eric kernel:  dev_uevent+0x10f/0x2d0
>> Sep 22 20:01:35 eric kernel:  kobject_uevent_env+0x291/0x680
>> Sep 22 20:01:35 eric kernel:  power_supply_unregister+0x8e/0xa0
>> Sep 22 20:01:35 eric kernel:  release_nodes+0x3d/0xb0
>> Sep 22 20:01:35 eric kernel:  devres_release_group+0xfc/0x130
>> Sep 22 20:01:35 eric kernel:  hid_device_remove+0x56/0xa0
>> Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
>> Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
>> Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
>> Sep 22 20:01:35 eric kernel:  ? __queue_work+0x1df/0x440
>> Sep 22 20:01:35 eric kernel:  hid_destroy_device+0x4b/0x60
>> Sep 22 20:01:35 eric kernel:  logi_dj_remove+0x9a/0x100 [hid_logitech_dj 5c91534a0ead2b65e04dd799a0437e3b99b21bc4]
>> Sep 22 20:01:35 eric kernel:  hid_device_remove+0x44/0xa0
>> Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
>> Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
>> Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
>> Sep 22 20:01:35 eric kernel:  ? __queue_work+0x1df/0x440
>> Sep 22 20:01:35 eric kernel:  hid_destroy_device+0x4b/0x60
>> Sep 22 20:01:35 eric kernel:  usbhid_disconnect+0x47/0x60 [usbhid 727dcc1c0b94e6b4418727a468398ac3bca492f3]
>> Sep 22 20:01:35 eric kernel:  usb_unbind_interface+0x90/0x270
>> Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
>> Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
>> Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
>> Sep 22 20:01:35 eric kernel:  ? kobject_put+0xa0/0x1d0
>> Sep 22 20:01:35 eric kernel:  usb_disable_device+0xcd/0x1e0
>> Sep 22 20:01:35 eric kernel:  usb_disconnect+0xde/0x2c0
>> Sep 22 20:01:35 eric kernel:  usb_disconnect+0xc3/0x2c0
>> Sep 22 20:01:35 eric kernel:  hub_event+0xe80/0x1c10
>>
>> There have been quite a few bug reports (see Link tags) about this crash.
>>
>> Fix all the TOCTOU issues, including the really bad power-supply related
>> system crash on USB disconnect, by making probe() use the workqueue for
>> running hidpp_connect_event() too, so that it can never run more then once.
>>
>> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227221
>> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227968
>> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227968
>> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2242189
>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217412#c58
> 
> Many thanks for finding out the root cause of this. And sorry that you
> had to do it :(
> 
> Out of curiosity, do you have an idea on when this was introduced?
> From these logs it seem that the symptoms started to appear in July in
> distributions, but I can not quickly reproduce it locally and so I'm a
> little bit puzzled.

I think this may be triggered more easily after commit 699fb50d99039
from 2023-07-20, but the root cause of this seems to be have been
with us all along ...

> Anyway, with or without a Fixes tag, I think I'll apply it today and
> send this and the other patch from Johan to Linus ASAP.

Note I realized this morning that there is another small race between
probe() and hidpp_connect_event() which should not cause a crahs but which
may cause functional issues..

So I'm preparing a follow up patch. I actually just finished testing
the follow up patch. Please also include that patch (assuming you agree
with the fix from it).

Regards,

Hans






>> Cc: stable@vger.kernel.org
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>>  drivers/hid/hid-logitech-hidpp.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
>> index ff077df0babf..a209d51bd247 100644
>> --- a/drivers/hid/hid-logitech-hidpp.c
>> +++ b/drivers/hid/hid-logitech-hidpp.c
>> @@ -4515,7 +4515,8 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
>>  			goto hid_hw_init_fail;
>>  	}
>>  
>> -	hidpp_connect_event(hidpp);
>> +	schedule_work(&hidpp->work);
>> +	flush_work(&hidpp->work);
>>  
>>  	if (will_restart) {
>>  		/* Reset the HID node state */
>> -- 
>> 2.41.0
>>
>
Hans de Goede Oct. 6, 2023, 8:50 a.m. UTC | #2
Hi,

On 10/5/23 20:26, Hans de Goede wrote:
> hidpp_connect_event() has *four* time-of-check vs time-of-use (TOCTOU)
> races when it races with itself.
> 
> hidpp_connect_event() primarily runs from a workqueue but it also runs
> on probe() and if a "device-connected" packet is received by the hw
> when the thread running hidpp_connect_event() from probe() is waiting on
> the hw, then a second thread running hidpp_connect_event() will be
> started from the workqueue.
> 
> This opens the following races (note the below code is simplified):
> 
> 1. Retrieving + printing the protocol (harmless race):
> 
> 	if (!hidpp->protocol_major) {
> 		hidpp_root_get_protocol_version()
> 		hidpp->protocol_major = response.rap.params[0];
> 	}
> 
> We can actually see this race hit in the dmesg in the abrt output
> attached to rhbz#2227968:
> 
> [ 3064.624215] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
> [ 3064.658184] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
> 
> Testing with extra logging added has shown that after this the 2 threads
> take turn grabbing the hw access mutex (send_mutex) so they ping-pong
> through all the other TOCTOU cases managing to hit all of them:
> 
> 2. Updating the name to the HIDPP name (harmless race):
> 
> 	if (hidpp->name == hdev->name) {
> 		...
> 		hidpp->name = new_name;
> 	}
> 
> 3. Initializing the power_supply class for the battery (problematic!):
> 
> hidpp_initialize_battery()
> {
>         if (hidpp->battery.ps)
>                 return 0;
> 
> 	probe_battery(); /* Blocks, threads take turns executing this */
> 
> 	hidpp->battery.desc.properties =
> 		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
> 
> 	hidpp->battery.ps =
> 		devm_power_supply_register(&hidpp->hid_dev->dev,
> 					   &hidpp->battery.desc, cfg);
> }
> 
> 4. Creating delayed input_device (potentially problematic):
> 
> 	if (hidpp->delayed_input)
> 		return;
> 
> 	hidpp->delayed_input = hidpp_allocate_input(hdev);
> 
> The really big problem here is 3. Hitting the race leads to the following
> sequence:
> 
> 	hidpp->battery.desc.properties =
> 		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
> 
> 	hidpp->battery.ps =
> 		devm_power_supply_register(&hidpp->hid_dev->dev,
> 					   &hidpp->battery.desc, cfg);
> 
> 	...
> 
> 	hidpp->battery.desc.properties =
> 		devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
> 
> 	hidpp->battery.ps =
> 		devm_power_supply_register(&hidpp->hid_dev->dev,
> 					   &hidpp->battery.desc, cfg);
> 
> So now we have registered 2 power supplies for the same battery,
> which looks a bit weird from userspace's pov but this is not even
> the really big problem.
> 
> Notice how:
> 
> 1. This is all devm-maganaged
> 2. The hidpp->battery.desc struct is shared between the 2 power supplies
> 3. hidpp->battery.desc points to the result from the second devm_kmemdup()

Small error in the commit msg here, please squash in a fix if possible, this
should read:

3. hidpp->battery.desc.properties points to the result from the second devm_kmemdup()


Regards,

Hans






> This causes a use after free scenario on USB disconnect of the receiver:
> 1. The last registered power supply class device gets unregistered
> 2. The memory from the last devm_kmemdup() call gets freed,
>    hidpp->battery.desc.properties now points to freed memory
> 3. The first registered power supply class device gets unregistered,
>    this involves sending a remove uevent to userspace which invokes
>    power_supply_uevent() to fill the uevent data
> 4. power_supply_uevent() uses hidpp->battery.desc.properties which
>    now points to freed memory leading to backtraces like this one:
> 
> Sep 22 20:01:35 eric kernel: BUG: unable to handle page fault for address: ffffb2140e017f08
> ...
> Sep 22 20:01:35 eric kernel: Workqueue: usb_hub_wq hub_event
> Sep 22 20:01:35 eric kernel: RIP: 0010:power_supply_uevent+0xee/0x1d0
> ...
> Sep 22 20:01:35 eric kernel:  ? asm_exc_page_fault+0x26/0x30
> Sep 22 20:01:35 eric kernel:  ? power_supply_uevent+0xee/0x1d0
> Sep 22 20:01:35 eric kernel:  ? power_supply_uevent+0x10d/0x1d0
> Sep 22 20:01:35 eric kernel:  dev_uevent+0x10f/0x2d0
> Sep 22 20:01:35 eric kernel:  kobject_uevent_env+0x291/0x680
> Sep 22 20:01:35 eric kernel:  power_supply_unregister+0x8e/0xa0
> Sep 22 20:01:35 eric kernel:  release_nodes+0x3d/0xb0
> Sep 22 20:01:35 eric kernel:  devres_release_group+0xfc/0x130
> Sep 22 20:01:35 eric kernel:  hid_device_remove+0x56/0xa0
> Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
> Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
> Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
> Sep 22 20:01:35 eric kernel:  ? __queue_work+0x1df/0x440
> Sep 22 20:01:35 eric kernel:  hid_destroy_device+0x4b/0x60
> Sep 22 20:01:35 eric kernel:  logi_dj_remove+0x9a/0x100 [hid_logitech_dj 5c91534a0ead2b65e04dd799a0437e3b99b21bc4]
> Sep 22 20:01:35 eric kernel:  hid_device_remove+0x44/0xa0
> Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
> Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
> Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
> Sep 22 20:01:35 eric kernel:  ? __queue_work+0x1df/0x440
> Sep 22 20:01:35 eric kernel:  hid_destroy_device+0x4b/0x60
> Sep 22 20:01:35 eric kernel:  usbhid_disconnect+0x47/0x60 [usbhid 727dcc1c0b94e6b4418727a468398ac3bca492f3]
> Sep 22 20:01:35 eric kernel:  usb_unbind_interface+0x90/0x270
> Sep 22 20:01:35 eric kernel:  device_release_driver_internal+0x19f/0x200
> Sep 22 20:01:35 eric kernel:  bus_remove_device+0xc6/0x130
> Sep 22 20:01:35 eric kernel:  device_del+0x15c/0x3f0
> Sep 22 20:01:35 eric kernel:  ? kobject_put+0xa0/0x1d0
> Sep 22 20:01:35 eric kernel:  usb_disable_device+0xcd/0x1e0
> Sep 22 20:01:35 eric kernel:  usb_disconnect+0xde/0x2c0
> Sep 22 20:01:35 eric kernel:  usb_disconnect+0xc3/0x2c0
> Sep 22 20:01:35 eric kernel:  hub_event+0xe80/0x1c10
> 
> There have been quite a few bug reports (see Link tags) about this crash.
> 
> Fix all the TOCTOU issues, including the really bad power-supply related
> system crash on USB disconnect, by making probe() use the workqueue for
> running hidpp_connect_event() too, so that it can never run more then once.
> 
> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227221
> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227968
> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2227968
> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2242189
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217412#c58
> Cc: stable@vger.kernel.org
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/hid/hid-logitech-hidpp.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
> index ff077df0babf..a209d51bd247 100644
> --- a/drivers/hid/hid-logitech-hidpp.c
> +++ b/drivers/hid/hid-logitech-hidpp.c
> @@ -4515,7 +4515,8 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
>  			goto hid_hw_init_fail;
>  	}
>  
> -	hidpp_connect_event(hidpp);
> +	schedule_work(&hidpp->work);
> +	flush_work(&hidpp->work);
>  
>  	if (will_restart) {
>  		/* Reset the HID node state */
Benjamin Tissoires Oct. 6, 2023, 2:12 p.m. UTC | #3
On Thu, 05 Oct 2023 20:26:38 +0200, Hans de Goede wrote:
> hidpp_connect_event() has *four* time-of-check vs time-of-use (TOCTOU)
> races when it races with itself.
> 
> hidpp_connect_event() primarily runs from a workqueue but it also runs
> on probe() and if a "device-connected" packet is received by the hw
> when the thread running hidpp_connect_event() from probe() is waiting on
> the hw, then a second thread running hidpp_connect_event() will be
> started from the workqueue.
> 
> [...]

Applied to hid/hid.git (for-6.6/upstream-fixes), thanks!

[1/1] HID: logitech-hidpp: Fix kernel crash on receiver USB disconnect
      https://git.kernel.org/hid/hid/c/dac501397b9d

Cheers,
diff mbox series

Patch

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index ff077df0babf..a209d51bd247 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -4515,7 +4515,8 @@  static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
 			goto hid_hw_init_fail;
 	}
 
-	hidpp_connect_event(hidpp);
+	schedule_work(&hidpp->work);
+	flush_work(&hidpp->work);
 
 	if (will_restart) {
 		/* Reset the HID node state */