{"cve":"CVE-2023-52478","nvd":{"published":"2024-02-29T06:15:45.920","modified":"2026-08-04T10:18:29.253","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: logitech-hidpp: Fix kernel crash on receiver USB disconnect\n\nhidpp_connect_event() has *four* time-of-check vs time-of-use (TOCTOU)\nraces when it races with itself.\n\nhidpp_connect_event() primarily runs from a workqueue but it also runs\non probe() and if a \"device-connected\" packet is received by the hw\nwhen the thread running hidpp_connect_event() from probe() is waiting on\nthe hw, then a second thread running hidpp_connect_event() will be\nstarted from the workqueue.\n\nThis opens the following races (note the below code is simplified):\n\n1. Retrieving + printing the protocol (harmless race):\n\n\tif (!hidpp->protocol_major) {\n\t\thidpp_root_get_protocol_version()\n\t\thidpp->protocol_major = response.rap.params[0];\n\t}\n\nWe can actually see this race hit in the dmesg in the abrt output\nattached to rhbz#2227968:\n\n[ 3064.624215] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.\n[ 3064.658184] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.\n\nTesting with extra logging added has shown that after this the 2 threads\ntake turn grabbing the hw access mutex (send_mutex) so they ping-pong\nthrough all the other TOCTOU cases managing to hit all of them:\n\n2. Updating the name to the HIDPP name (harmless race):\n\n\tif (hidpp->name == hdev->name) {\n\t\t...\n\t\thidpp->name = new_name;\n\t}\n\n3. Initializing the power_supply class for the battery (problematic!):\n\nhidpp_initialize_battery()\n{\n        if (hidpp->battery.ps)\n                return 0;\n\n\tprobe_battery(); /* Blocks, threads take turns executing this */\n\n\thidpp->battery.desc.properties =\n\t\tdevm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);\n\n\thidpp->battery.ps =\n\t\tdevm_power_supply_register(&hidpp->hid_dev->dev,\n\t\t\t\t\t   &hidpp->battery.desc, cfg);\n}\n\n4. Creating delayed input_device (potentially problematic):\n\n\tif (hidpp->delayed_input)\n\t\treturn;\n\n\thidpp->delayed_input = hidpp_allocate_input(hdev);\n\nThe really big problem here is 3. Hitting the race leads to the following\nsequence:\n\n\thidpp->battery.desc.properties =\n\t\tdevm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);\n\n\thidpp->battery.ps =\n\t\tdevm_power_supply_register(&hidpp->hid_dev->dev,\n\t\t\t\t\t   &hidpp->battery.desc, cfg);\n\n\t...\n\n\thidpp->battery.desc.properties =\n\t\tdevm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);\n\n\thidpp->battery.ps =\n\t\tdevm_power_supply_register(&hidpp->hid_dev->dev,\n\t\t\t\t\t   &hidpp->battery.desc, cfg);\n\nSo now we have registered 2 power supplies for the same battery,\nwhich looks a bit weird from userspace's pov but this is not even\nthe really big problem.\n\nNotice how:\n\n1. This is all devm-maganaged\n2. The hidpp->battery.desc struct is shared between the 2 power supplies\n3. hidpp->battery.desc.properties points to the result from the second\n   devm_kmemdup()\n\nThis causes a use after free scenario on USB disconnect of the receiver:\n1. The last registered power supply class device gets unregistered\n2. The memory from the last devm_kmemdup() call gets freed,\n   hidpp->battery.desc.properties now points to freed memory\n3. The first registered power supply class device gets unregistered,\n   this involves sending a remove uevent to userspace which invokes\n   power_supply_uevent() to fill the uevent data\n4. power_supply_uevent() uses hidpp->battery.desc.properties which\n   now points to freed memory leading to backtraces like this one:\n\nSep 22 20:01:35 eric kernel: BUG: unable to handle page fault for address: ffffb2140e017f08\n...\nSep 22 20:01:35 eric kernel: Workqueue: usb_hub_wq hub_event\nSep 22 20:01:35 eric kernel: RIP: 0010:power_supply_uevent+0xee/0x1d0\n...\nSep 22 20:01:35 eric kernel:  ? asm_exc_page_fault+0x26/0x30\nSep 22 20:01:35 eric kernel:  ? power_supply_uevent+0xee/0x1d0\nSep 22 20:01:35 eric kernel:  ? power_supply_uevent+0x10d/0x1d0\nSep 22 20:01:35 eric kernel:  dev_uevent+0x10f/0x2d0\nSep 22 20:01:35 eric kernel:  kobject_uevent_env+0x291/0x680\nSep 22 20:01:35 eric kernel:  \n---truncated---","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":4.7},"cwes":["CWE-367"],"references":["https://git.kernel.org/stable/c/093af62c023537f097d2ebdfaa0bc7c1a6e874e1","https://git.kernel.org/stable/c/28ddc1e0b898291323b62d770b1b931de131a528","https://git.kernel.org/stable/c/44481b244fcaa2b895a53081d6204c574720c38c","https://git.kernel.org/stable/c/ca0c4cc1d215dc22ab0e738c9f017c650f3183f5","https://git.kernel.org/stable/c/cd0e2bf7fb22fe9b989c59c42dca06367fd10e6b"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:46:54.846886191+00:00"},"epss":{"cve":"CVE-2023-52478","score":0.00253,"percentile":0.16905,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}