Description

In the Linux kernel, the following vulnerability has been resolved:

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

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()
{
...

Classification

CVE ID: CVE-2023-52478

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 5.08% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/ca0c4cc1d215dc22ab0e738c9f017c650f3183f5
https://git.kernel.org/stable/c/44481b244fcaa2b895a53081d6204c574720c38c
https://git.kernel.org/stable/c/cd0e2bf7fb22fe9b989c59c42dca06367fd10e6b
https://git.kernel.org/stable/c/093af62c023537f097d2ebdfaa0bc7c1a6e874e1
https://git.kernel.org/stable/c/28ddc1e0b898291323b62d770b1b931de131a528
https://git.kernel.org/stable/c/fd72ac9556a473fc7daf54efb6ca8a97180d621d
https://git.kernel.org/stable/c/f7b2c7d9831af99369fe8ad9b2a68d78942f414e
https://git.kernel.org/stable/c/dac501397b9d81e4782232c39f94f4307b137452

Timeline