--- id: CVE-2023-52478 title: |- 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… summary: |- 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… severity: high cvss: 8.8 cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H' cwe: - CWE-367 vendor: linux product: linux_kernel affected: - linux_kernel < 4.14.328 - 'linux_kernel >= 4.15, < 4.19.297' - 'linux_kernel >= 4.20, < 5.4.259' - 'linux_kernel >= 5.5, < 5.10.199' - 'linux_kernel >= 5.11, < 5.15.136' - 'linux_kernel >= 5.16, < 6.1.59' - 'linux_kernel >= 6.2, < 6.5.8' - linux_kernel = 6.6 patched: - linux_kernel 6.5.8 published: '2024-02-29' updated: '2026-08-04' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-52478' references: - url: 'https://git.kernel.org/stable/c/093af62c023537f097d2ebdfaa0bc7c1a6e874e1' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/28ddc1e0b898291323b62d770b1b931de131a528' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/44481b244fcaa2b895a53081d6204c574720c38c' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/ca0c4cc1d215dc22ab0e738c9f017c650f3183f5' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/cd0e2bf7fb22fe9b989c59c42dca06367fd10e6b' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/dac501397b9d81e4782232c39f94f4307b137452' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/f7b2c7d9831af99369fe8ad9b2a68d78942f414e' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/fd72ac9556a473fc7daf54efb6ca8a97180d621d' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/093af62c023537f097d2ebdfaa0bc7c1a6e874e1' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/28ddc1e0b898291323b62d770b1b931de131a528' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/44481b244fcaa2b895a53081d6204c574720c38c' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/ca0c4cc1d215dc22ab0e738c9f017c650f3183f5' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/cd0e2bf7fb22fe9b989c59c42dca06367fd10e6b' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/dac501397b9d81e4782232c39f94f4307b137452' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/f7b2c7d9831af99369fe8ad9b2a68d78942f414e' label: af854a3a-2127-422b-91ae-364da2661108 - url: 'https://git.kernel.org/stable/c/fd72ac9556a473fc7daf54efb6ca8a97180d621d' label: af854a3a-2127-422b-91ae-364da2661108 tags: - nvd epss: 0.00251 epssPercentile: 0.14726 ingestedAt: '2026-08-04T10:39:39.626Z' --- ## Overview 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() { 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.properties 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: ---truncated--- ## Affected - `linux_kernel < 4.14.328` - `linux_kernel >= 4.15, < 4.19.297` - `linux_kernel >= 4.20, < 5.4.259` - `linux_kernel >= 5.5, < 5.10.199` - `linux_kernel >= 5.11, < 5.15.136` - `linux_kernel >= 5.16, < 6.1.59` - `linux_kernel >= 6.2, < 6.5.8` - `linux_kernel = 6.6` ## Remediation Upgrade past the affected range: - `linux_kernel 6.5.8`