{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2022-49394 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2022-49394 is a medium-severity denial of service vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2022-49394 and fix it if it is affected.\n\nWhat it is: CVE-2022-49394 is a medium-severity denial of service vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2022-49394 in the wild and no public exploit code.\n\nAffected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2022-49394/ (Markdown: https://insights.sbomify.com/CVE-2022-49394/index.md)","id":"CVE-2022-49394","markdown":"https://insights.sbomify.com/CVE-2022-49394/index.md","name":"CVE-2022-49394","record":{"aliases":["DEBIAN-CVE-2022-49394","GHSA-896c-jr9v-xc8g","UBUNTU-CVE-2022-49394"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A race condition in the Linux kernel's blk-iolatency module can cause IO hangs and denial of service when cgroups are removed while IO is active.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"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't 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't 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 '8:0 target=100000' \u003e /sys/fs/cgroup/test/io.latency\n      sleep 1\n      rmdir /sys/fs/cgroup/test\n      sleep 1\n  done\n\nand there's 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['blkcg_root'].css.address_of_()):\n        for pos in hlist_for_each(container_of(css, 'struct blkcg', 'css').blkg_list):\n            blkg = container_of(pos, 'struct blkcg_gq', 'blkcg_node')\n            pd = blkg.pd[prog['blkcg_policy_iolatency'].plid]\n            if pd.value_() == 0:\n                continue\n            iolat = container_of(pd, 'struct iolatency_grp', 'pd')\n            inflight = iolat.rq_wait.inflight.counter.value_()\n            if inflight:\n                print(f'inflight={inflight} {disk_name(blkg.q.disk).decode(\"utf-8\")} '\n                      f'{cgroup_path(css.cgroup).decode(\"utf-8\")}')\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's 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's latency target\nis newly set or cleared.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"blk-iolatency: Fix inflight count imbalances and IO hangs on offline","id":"CVE-2022-49394","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2022"},"n_packages":0,"n_references":7,"next":{"headline":"um: Fix out-of-bounds read in LDT setup","id":"CVE-2022-49395"},"packages":[],"prev":{"headline":"misc: fastrpc: fix list iterator in fastrpc_req_mem_unmap_impl","id":"CVE-2022-49393"},"products":["Linux"],"published":"2025-02-26","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-23","vendors":["Linux"]},"summary":"A race condition in the Linux kernel's blk-iolatency module can cause IO hangs and denial of service when cgroups are removed while IO is active.","url":"https://insights.sbomify.com/CVE-2022-49394/"}