# CVE-2022-49900: linux: In the Linux kernel, the following vulnerability has been resolved: i2c: piix4: Fix adapter not be removed in piix4_... CVE-2022-49900 is fixed in linux on 1 platform, first by DEBIAN-CVE-2022-49900, released May 1, 2025. It is not reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/cve/CVE-2022-49900 - Priority: High - CVSS: 7.8 (high) - EPSS: 0.0021 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: May 1, 2025 ## Description In the Linux kernel, the following vulnerability has been resolved: i2c: piix4: Fix adapter not be removed in piix4_remove() In piix4_probe(), the piix4 adapter will be registered in: piix4_probe() piix4_add_adapters_sb800() / piix4_add_adapter() i2c_add_adapter() Based on the probed device type, piix4_add_adapters_sb800() or single piix4_add_adapter() will be called. For the former case, piix4_adapter_count is set as the number of adapters, while for antoher case it is not set and kept default *zero*. When piix4 is removed, piix4_remove() removes the adapters added in piix4_probe(), basing on the piix4_adapter_count value. Because the count is zero for the single adapter case, the adapter won't be removed and makes the sources allocated for adapter leaked, such as the i2c client and device. These sources can still be accessed by i2c or bus and cause problems. An easily reproduced case is that if a new adapter is registered, i2c will get the leaked adapter and try to call smbus_algorithm, which was already freed: Triggered by: rmmod i2c_piix4 && modprobe max31730 BUG: unable to handle page fault for address: ffffffffc053d860 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 3752 Comm: modprobe Tainted: G Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:i2c_default_probe (drivers/i2c/i2c-core-base.c:2259) i2c_core RSP: 0018:ffff888107477710 EFLAGS: 00000246 ... i2c_detect (drivers/i2c/i2c-core-base.c:2302) i2c_core __process_new_driver (drivers/i2c/i2c-core-base.c:1336) i2c_core bus_for_each_dev (drivers/base/bus.c:301) i2c_for_each_dev (drivers/i2c/i2c-core-base.c:1823) i2c_core i2c_register_driver (drivers/i2c/i2c-core-base.c:1861) i2c_core do_one_initcall (init/main.c:1296) do_init_module (kernel/module/main.c:2455) ... ---[ end trace 0000000000000000 ]--- Fix this problem by correctly set piix4_adapter_count as 1 for the single adapter so it can be normally removed. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | linux Debian 12.15 (bookworm) | 6.0.8-1 | [DEBIAN-CVE-2022-49900](https://patchblox.com/security/data/fix/linux/debian-cve-2022-49900.md) | May 1, 2025 | | Linux | linux Debian 13.5 (trixie) | 6.0.8-1 | [DEBIAN-CVE-2022-49900](https://patchblox.com/security/data/fix/linux/debian-cve-2022-49900.md) | May 1, 2025 | | Linux | linux Debian 14 | 6.0.8-1 | [DEBIAN-CVE-2022-49900](https://patchblox.com/security/data/fix/linux/debian-cve-2022-49900.md) | May 1, 2025 | --- Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.