Vulnerability-Lookup

BDU:2026-03899 (CVE-2022-49394)

Vulnerability from fstec – Published: 2026-03-26 – Updated: 2026-03-26 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции blkcg_iolatency_throttle() модуля block/blk-iolatency.c поддержки блочного уровня ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость функции blkcg_iolatency_throttle() модуля block/blk-iolatency.c поддержки блочного уровня ядра операционной системы Linux связана с некорректной зачисткой или освобождением ресурсов. Эксплуатация уязвимости может позволить нарушителю вызвать отказ в обслуживании

Severity

4.6 (Medium) CVSS 2.0


                      
                        AV:L/AC:L/Au:S/C:N/I:N/A:C

5.5 (Medium) CVSS 3.1


                      
                        CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Resource exhaustion

Incidents

Being clarified

Remediation

Software update

CWE

CWE-404 - Некорректная зачистка или освобождение ресурсов

Aliases

CVE-2022-49394, RHSA-2022:8267

References

18 references

URL
https://git.kernel.org/stable/c/515d077ee3085ae343b6bea7fd031f9906645f38
https://git.kernel.org/stable/c/968f7a239c590454ffba79c126fbe0e963a0ba78
https://git.kernel.org/stable/c/77692c02e1517c54f2fd0535f41aa4286ac9f140
https://git.kernel.org/stable/c/a30acbb5dfb7bcc813ad6a18ca31011ac44e5547
https://git.kernel.org/stable/c/5b0ff3ebbef791341695b718f8d2870869cf1d01
https://git.kernel.org/stable/c/d19fa8f252000d141f9199ca32959c50314e1f05
https://www.cve.org/CVERecord?id=CVE-2022-49394
https://lore.kernel.org/linux-cve-announce/2025022649-CVE-2022-49394-bcce@gregkh/
https://git.kernel.org/linus/8a177a36da6c54c98b8685d4f914cb3637d53c0d
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.247
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.198
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.121
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.46
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.14
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.18.3
https://access.redhat.com/security/cve/cve-2022-49394
https://security-tracker.debian.org/tracker/CVE-2022-49394
https://ubuntu.com/security/CVE-2022-49394

Impacted products

4 products from 4 vendors

Vendors

Canonical Ltd., Сообщество свободного программного обеспечения, Red Hat, Inc.

Products

Ubuntu, Debian GNU/Linux, Red Hat Enterprise Linux, Linux

Versions

18.04 LTS (Ubuntu), 20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), от 5.5 до 5.10.120 включительно (Linux), от 5.11 до 5.15.45 включительно (Linux), от 5.16 до 5.17.13 включительно (Linux), от 5.18 до 5.18.2 включительно (Linux), от 4.19.29 до 4.19.246 включительно (Linux), от 4.20.16 до 5.4.197 включительно (Linux)

Product types

Operating system

Platforms

Canonical Ltd. Ubuntu 18.04 LTS, Canonical Ltd. Ubuntu 20.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 11, Canonical Ltd. Ubuntu 22.04 LTS, Red Hat, Inc. Red Hat Enterprise Linux 9, Сообщество свободного программного обеспечения Linux от 5.5 до 5.10.120 включительно, Сообщество свободного программного обеспечения Linux от 5.11 до 5.15.45 включительно, Сообщество свободного программного обеспечения Linux от 5.16 до 5.17.13 включительно, Сообщество свободного программного обеспечения Linux от 5.18 до 5.18.2 включительно, Сообщество свободного программного обеспечения Linux от 4.19.29 до 4.19.246 включительно, Сообщество свободного программного обеспечения Linux от 4.20.16 до 5.4.197 включительно

Mitigations

В условиях отсутствия обновлений безопасности от производителя рекомендуется придерживаться "Рекомендаций по безопасной настройке операционных систем LINUX", изложенных в методическом документе ФСТЭК России, утверждённом 25 декабря 2022 года. Использование рекомендаций: Для Linux: https://git.kernel.org/stable/c/515d077ee3085ae343b6bea7fd031f9906645f38 https://git.kernel.org/stable/c/968f7a239c590454ffba79c126fbe0e963a0ba78 https://git.kernel.org/stable/c/77692c02e1517c54f2fd0535f41aa4286ac9f140 https://git.kernel.org/stable/c/a30acbb5dfb7bcc813ad6a18ca31011ac44e5547 https://git.kernel.org/stable/c/5b0ff3ebbef791341695b718f8d2870869cf1d01 https://git.kernel.org/stable/c/d19fa8f252000d141f9199ca32959c50314e1f05 Для программных продуктов Red Hat Inc.: https://access.redhat.com/security/cve/cve-2022-49394 Для программных продуктов Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2022-49394 Для программных продуктов Ubuntu: https://ubuntu.com/security/CVE-2022-49394

JSON

To clipboard

{
  "CVSS 2.0": "AV:L/AC:L/Au:S/C:N/I:N/A:C",
  "CVSS 3.0": "AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Canonical Ltd., \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f, Red Hat, Inc.",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "18.04 LTS (Ubuntu), 20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), \u043e\u0442 5.5 \u0434\u043e 5.10.120 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.11 \u0434\u043e 5.15.45 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.16 \u0434\u043e 5.17.13 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.18 \u0434\u043e 5.18.2 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.19.29 \u0434\u043e 4.19.246 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.20.16 \u0434\u043e 5.4.197 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0412 \u0443\u0441\u043b\u043e\u0432\u0438\u044f\u0445 \u043e\u0442\u0441\u0443\u0442\u0441\u0442\u0432\u0438\u044f \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0439 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u043e\u0442 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0443\u0435\u0442\u0441\u044f \u043f\u0440\u0438\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u0442\u044c\u0441\u044f \"\u0420\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439 \u043f\u043e \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0439 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0435 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c LINUX\", \u0438\u0437\u043b\u043e\u0436\u0435\u043d\u043d\u044b\u0445 \u0432 \u043c\u0435\u0442\u043e\u0434\u0438\u0447\u0435\u0441\u043a\u043e\u043c \u0434\u043e\u043a\u0443\u043c\u0435\u043d\u0442\u0435 \u0424\u0421\u0422\u042d\u041a \u0420\u043e\u0441\u0441\u0438\u0438, \u0443\u0442\u0432\u0435\u0440\u0436\u0434\u0451\u043d\u043d\u043e\u043c 25 \u0434\u0435\u043a\u0430\u0431\u0440\u044f 2022 \u0433\u043e\u0434\u0430.\n\n\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\n\u0414\u043b\u044f Linux:\nhttps://git.kernel.org/stable/c/515d077ee3085ae343b6bea7fd031f9906645f38\nhttps://git.kernel.org/stable/c/968f7a239c590454ffba79c126fbe0e963a0ba78\nhttps://git.kernel.org/stable/c/77692c02e1517c54f2fd0535f41aa4286ac9f140\nhttps://git.kernel.org/stable/c/a30acbb5dfb7bcc813ad6a18ca31011ac44e5547\nhttps://git.kernel.org/stable/c/5b0ff3ebbef791341695b718f8d2870869cf1d01\nhttps://git.kernel.org/stable/c/d19fa8f252000d141f9199ca32959c50314e1f05\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u044b\u0445 \u043f\u0440\u043e\u0434\u0443\u043a\u0442\u043e\u0432 Red Hat Inc.:\nhttps://access.redhat.com/security/cve/cve-2022-49394\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u044b\u0445 \u043f\u0440\u043e\u0434\u0443\u043a\u0442\u043e\u0432 Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2022-49394\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u044b\u0445 \u043f\u0440\u043e\u0434\u0443\u043a\u0442\u043e\u0432 Ubuntu:\nhttps://ubuntu.com/security/CVE-2022-49394",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "26.05.2022",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "26.03.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "26.03.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-03899",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2022-49394, RHSA-2022:8267",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Ubuntu, Debian GNU/Linux, Red Hat Enterprise Linux, Linux",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": "Canonical Ltd. Ubuntu 18.04 LTS , Canonical Ltd. Ubuntu 20.04 LTS , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 11 , Canonical Ltd. Ubuntu 22.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 9 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.5 \u0434\u043e 5.10.120 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.11 \u0434\u043e 5.15.45 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.16 \u0434\u043e 5.17.13 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.18 \u0434\u043e 5.18.2 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 4.19.29 \u0434\u043e 4.19.246 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 4.20.16 \u0434\u043e 5.4.197 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e ",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 blkcg_iolatency_throttle() \u043c\u043e\u0434\u0443\u043b\u044f block/blk-iolatency.c \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0438 \u0431\u043b\u043e\u0447\u043d\u043e\u0433\u043e \u0443\u0440\u043e\u0432\u043d\u044f \u044f\u0434\u0440\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Linux, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u0430\u044f \u0437\u0430\u0447\u0438\u0441\u0442\u043a\u0430 \u0438\u043b\u0438 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432 (CWE-404)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 blkcg_iolatency_throttle() \u043c\u043e\u0434\u0443\u043b\u044f block/blk-iolatency.c \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0438 \u0431\u043b\u043e\u0447\u043d\u043e\u0433\u043e \u0443\u0440\u043e\u0432\u043d\u044f \u044f\u0434\u0440\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Linux \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u043e\u0439 \u0437\u0430\u0447\u0438\u0441\u0442\u043a\u043e\u0439 \u0438\u043b\u0438 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435\u043c \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u0418\u0441\u0447\u0435\u0440\u043f\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://git.kernel.org/stable/c/515d077ee3085ae343b6bea7fd031f9906645f38\nhttps://git.kernel.org/stable/c/968f7a239c590454ffba79c126fbe0e963a0ba78\nhttps://git.kernel.org/stable/c/77692c02e1517c54f2fd0535f41aa4286ac9f140\nhttps://git.kernel.org/stable/c/a30acbb5dfb7bcc813ad6a18ca31011ac44e5547\nhttps://git.kernel.org/stable/c/5b0ff3ebbef791341695b718f8d2870869cf1d01\nhttps://git.kernel.org/stable/c/d19fa8f252000d141f9199ca32959c50314e1f05\nhttps://www.cve.org/CVERecord?id=CVE-2022-49394\nhttps://lore.kernel.org/linux-cve-announce/2025022649-CVE-2022-49394-bcce@gregkh/\nhttps://git.kernel.org/linus/8a177a36da6c54c98b8685d4f914cb3637d53c0d\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.247\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.198\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.121\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.46\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.14\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.18.3\nhttps://access.redhat.com/security/cve/cve-2022-49394\nhttps://security-tracker.debian.org/tracker/CVE-2022-49394\nhttps://ubuntu.com/security/CVE-2022-49394",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u0430\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u0430",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-404",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 4,6)\n\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 5,5)"
}

CVE-2022-49394 (GCVE-0-2022-49394)

Vulnerability from cvelistv5 – Published: 2025-02-26 02:11 – Updated: 2026-05-23 15:22

Title

blk-iolatency: Fix inflight count imbalances and IO hangs on offline

Summary

In the Linux kernel, the following vulnerability has been resolved: blk-iolatency: Fix inflight count imbalances and IO hangs on offline iolatency needs to track the number of inflight IOs per cgroup. As this tracking can be expensive, it is disabled when no cgroup has iolatency configured for the device. To ensure that the inflight counters stay balanced, iolatency_set_limit() freezes the request_queue while manipulating the enabled counter, which ensures that no IO is in flight and thus all counters are zero. Unfortunately, iolatency_set_limit() isn't the only place where the enabled counter is manipulated. iolatency_pd_offline() can also dec the counter and trigger disabling. As this disabling happens without freezing the q, this can easily happen while some IOs are in flight and thus leak the counts. This can be easily demonstrated by turning on iolatency on an one empty cgroup while IOs are in flight in other cgroups and then removing the cgroup. Note that iolatency shouldn't have been enabled elsewhere in the system to ensure that removing the cgroup disables iolatency for the whole device. The following keeps flipping on and off iolatency on sda: echo +io > /sys/fs/cgroup/cgroup.subtree_control while true; do mkdir -p /sys/fs/cgroup/test echo '8:0 target=100000' > /sys/fs/cgroup/test/io.latency sleep 1 rmdir /sys/fs/cgroup/test sleep 1 done and there's concurrent fio generating direct rand reads: fio --name test --filename=/dev/sda --direct=1 --rw=randread \ --runtime=600 --time_based --iodepth=256 --numjobs=4 --bs=4k while monitoring with the following drgn script: while True: for css in css_for_each_descendant_pre(prog['blkcg_root'].css.address_of_()): for pos in hlist_for_each(container_of(css, 'struct blkcg', 'css').blkg_list): blkg = container_of(pos, 'struct blkcg_gq', 'blkcg_node') pd = blkg.pd[prog['blkcg_policy_iolatency'].plid] if pd.value_() == 0: continue iolat = container_of(pd, 'struct iolatency_grp', 'pd') inflight = iolat.rq_wait.inflight.counter.value_() if inflight: print(f'inflight={inflight} {disk_name(blkg.q.disk).decode("utf-8")} ' f'{cgroup_path(css.cgroup).decode("utf-8")}') time.sleep(1) The monitoring output looks like the following: inflight=1 sda /user.slice inflight=1 sda /user.slice ... inflight=14 sda /user.slice inflight=13 sda /user.slice inflight=17 sda /user.slice inflight=15 sda /user.slice inflight=18 sda /user.slice inflight=17 sda /user.slice inflight=20 sda /user.slice inflight=19 sda /user.slice <- fio stopped, inflight stuck at 19 inflight=19 sda /user.slice inflight=19 sda /user.slice If a cgroup with stuck inflight ends up getting throttled, the throttled IOs will never get issued as there's no completion event to wake it up leading to an indefinite hang. This patch fixes the bug by unifying enable handling into a work item which is automatically kicked off from iolatency_set_min_lat_nsec() which is called from both iolatency_set_limit() and iolatency_pd_offline() paths. Punting to a work item is necessary as iolatency_pd_offline() is called under spinlocks while freezing a request_queue requires a sleepable context. This also simplifies the code reducing LOC sans the comments and avoids the unnecessary freezes which were happening whenever a cgroup's latency target is newly set or cleared.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/515d077ee3085ae34…
https://git.kernel.org/stable/c/d19fa8f252000d141…
https://git.kernel.org/stable/c/77692c02e1517c54f…
https://git.kernel.org/stable/c/a30acbb5dfb7bcc81…
https://git.kernel.org/stable/c/968f7a239c590454f…
https://git.kernel.org/stable/c/5b0ff3ebbef791341…
https://git.kernel.org/stable/c/8a177a36da6c54c98…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 6d482bc5697763eb1214f207286daa201b32d20a , < 515d077ee3085ae343b6bea7fd031f9906645f38 (git) Affected: 8c772a9bfc7c07c76f4a58b58910452fbb20843b , < d19fa8f252000d141f9199ca32959c50314e1f05 (git) Affected: 8c772a9bfc7c07c76f4a58b58910452fbb20843b , < 77692c02e1517c54f2fd0535f41aa4286ac9f140 (git) Affected: 8c772a9bfc7c07c76f4a58b58910452fbb20843b , < a30acbb5dfb7bcc813ad6a18ca31011ac44e5547 (git) Affected: 8c772a9bfc7c07c76f4a58b58910452fbb20843b , < 968f7a239c590454ffba79c126fbe0e963a0ba78 (git) Affected: 8c772a9bfc7c07c76f4a58b58910452fbb20843b , < 5b0ff3ebbef791341695b718f8d2870869cf1d01 (git) Affected: 8c772a9bfc7c07c76f4a58b58910452fbb20843b , < 8a177a36da6c54c98b8685d4f914cb3637d53c0d (git) Affected: beed6109acd4efc2f1717c31bddcd0ad7ebbf253 (git) Affected: 4.19.29 , < 4.19.247 (semver) Affected: 4.20.16 , < 4.21 (semver)
Linux	Linux	Affected: 5.0 Unaffected: 0 , < 5.0 (semver) Unaffected: 4.19.247 , ≤ 4.19.* (semver) Unaffected: 5.4.198 , ≤ 5.4.* (semver) Unaffected: 5.10.121 , ≤ 5.10.* (semver) Unaffected: 5.15.46 , ≤ 5.15.* (semver) Unaffected: 5.17.14 , ≤ 5.17.* (semver) Unaffected: 5.18.3 , ≤ 5.18.* (semver) Unaffected: 5.19 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "block/blk-iolatency.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "versionType": "semver"
            }
          ]
        },
        {
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          "product": "Linux",
          "programFiles": [
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.0"
            },
            {
              "lessThan": "5.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.19.*",
              "status": "unaffected",
              "version": "4.19.247",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.198",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.121",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.46",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.17.*",
              "status": "unaffected",
              "version": "5.17.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.18.*",
              "status": "unaffected",
              "version": "5.18.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.19",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
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                },
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                },
                {
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                },
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                },
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                },
                {
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                  "versionEndExcluding": "5.18.3",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.20.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblk-iolatency: Fix inflight count imbalances and IO hangs on offline\n\niolatency needs to track the number of inflight IOs per cgroup. As this\ntracking can be expensive, it is disabled when no cgroup has iolatency\nconfigured for the device. To ensure that the inflight counters stay\nbalanced, iolatency_set_limit() freezes the request_queue while manipulating\nthe enabled counter, which ensures that no IO is in flight and thus all\ncounters are zero.\n\nUnfortunately, iolatency_set_limit() isn\u0027t the only place where the enabled\ncounter is manipulated. iolatency_pd_offline() can also dec the counter and\ntrigger disabling. As this disabling happens without freezing the q, this\ncan easily happen while some IOs are in flight and thus leak the counts.\n\nThis can be easily demonstrated by turning on iolatency on an one empty\ncgroup while IOs are in flight in other cgroups and then removing the\ncgroup. Note that iolatency shouldn\u0027t have been enabled elsewhere in the\nsystem to ensure that removing the cgroup disables iolatency for the whole\ndevice.\n\nThe following keeps flipping on and off iolatency on sda:\n\n  echo +io \u003e /sys/fs/cgroup/cgroup.subtree_control\n  while true; do\n      mkdir -p /sys/fs/cgroup/test\n      echo \u00278:0 target=100000\u0027 \u003e /sys/fs/cgroup/test/io.latency\n      sleep 1\n      rmdir /sys/fs/cgroup/test\n      sleep 1\n  done\n\nand there\u0027s concurrent fio generating direct rand reads:\n\n  fio --name test --filename=/dev/sda --direct=1 --rw=randread \\\n      --runtime=600 --time_based --iodepth=256 --numjobs=4 --bs=4k\n\nwhile monitoring with the following drgn script:\n\n  while True:\n    for css in css_for_each_descendant_pre(prog[\u0027blkcg_root\u0027].css.address_of_()):\n        for pos in hlist_for_each(container_of(css, \u0027struct blkcg\u0027, \u0027css\u0027).blkg_list):\n            blkg = container_of(pos, \u0027struct blkcg_gq\u0027, \u0027blkcg_node\u0027)\n            pd = blkg.pd[prog[\u0027blkcg_policy_iolatency\u0027].plid]\n            if pd.value_() == 0:\n                continue\n            iolat = container_of(pd, \u0027struct iolatency_grp\u0027, \u0027pd\u0027)\n            inflight = iolat.rq_wait.inflight.counter.value_()\n            if inflight:\n                print(f\u0027inflight={inflight} {disk_name(blkg.q.disk).decode(\"utf-8\")} \u0027\n                      f\u0027{cgroup_path(css.cgroup).decode(\"utf-8\")}\u0027)\n    time.sleep(1)\n\nThe monitoring output looks like the following:\n\n  inflight=1 sda /user.slice\n  inflight=1 sda /user.slice\n  ...\n  inflight=14 sda /user.slice\n  inflight=13 sda /user.slice\n  inflight=17 sda /user.slice\n  inflight=15 sda /user.slice\n  inflight=18 sda /user.slice\n  inflight=17 sda /user.slice\n  inflight=20 sda /user.slice\n  inflight=19 sda /user.slice \u003c- fio stopped, inflight stuck at 19\n  inflight=19 sda /user.slice\n  inflight=19 sda /user.slice\n\nIf a cgroup with stuck inflight ends up getting throttled, the throttled IOs\nwill never get issued as there\u0027s no completion event to wake it up leading\nto an indefinite hang.\n\nThis patch fixes the bug by unifying enable handling into a work item which\nis automatically kicked off from iolatency_set_min_lat_nsec() which is\ncalled from both iolatency_set_limit() and iolatency_pd_offline() paths.\nPunting to a work item is necessary as iolatency_pd_offline() is called\nunder spinlocks while freezing a request_queue requires a sleepable context.\n\nThis also simplifies the code reducing LOC sans the comments and avoids the\nunnecessary freezes which were happening whenever a cgroup\u0027s latency target\nis newly set or cleared."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T15:22:05.063Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/515d077ee3085ae343b6bea7fd031f9906645f38"
        },
        {
          "url": "https://git.kernel.org/stable/c/d19fa8f252000d141f9199ca32959c50314e1f05"
        },
        {
          "url": "https://git.kernel.org/stable/c/77692c02e1517c54f2fd0535f41aa4286ac9f140"
        },
        {
          "url": "https://git.kernel.org/stable/c/a30acbb5dfb7bcc813ad6a18ca31011ac44e5547"
        },
        {
          "url": "https://git.kernel.org/stable/c/968f7a239c590454ffba79c126fbe0e963a0ba78"
        },
        {
          "url": "https://git.kernel.org/stable/c/5b0ff3ebbef791341695b718f8d2870869cf1d01"
        },
        {
          "url": "https://git.kernel.org/stable/c/8a177a36da6c54c98b8685d4f914cb3637d53c0d"
        }
      ],
      "title": "blk-iolatency: Fix inflight count imbalances and IO hangs on offline",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2022-49394",
    "datePublished": "2025-02-26T02:11:25.197Z",
    "dateReserved": "2025-02-26T02:08:31.562Z",
    "dateUpdated": "2026-05-23T15:22:05.063Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

RHSA-2022:8267

Vulnerability from csaf_redhat - Published: 2022-11-15 11:55 - Updated: 2026-09-17 12:16

Summary

Red Hat Security Advisory: kernel security, bug fix, and enhancement update

Severity

Moderate

Scope

195 vulnerabilities in this advisory.

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

BDU:2026-03899 (CVE-2022-49394)

CVE-2022-49394 (GCVE-0-2022-49394)

RHSA-2022:8267

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