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CVE-2022-49081 (GCVE-0-2022-49081)

Vulnerability from cvelistv5 – Published: 2025-02-26 01:54 – Updated: 2026-05-11 18:52
VLAI
Title
highmem: fix checks in __kmap_local_sched_{in,out}
Summary
In the Linux kernel, the following vulnerability has been resolved: highmem: fix checks in __kmap_local_sched_{in,out} When CONFIG_DEBUG_KMAP_LOCAL is enabled __kmap_local_sched_{in,out} check that even slots in the tsk->kmap_ctrl.pteval are unmapped. The slots are initialized with 0 value, but the check is done with pte_none. 0 pte however does not necessarily mean that pte_none will return true. e.g. on xtensa it returns false, resulting in the following runtime warnings: WARNING: CPU: 0 PID: 101 at mm/highmem.c:627 __kmap_local_sched_out+0x51/0x108 CPU: 0 PID: 101 Comm: touch Not tainted 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13 Call Trace: dump_stack+0xc/0x40 __warn+0x8f/0x174 warn_slowpath_fmt+0x48/0xac __kmap_local_sched_out+0x51/0x108 __schedule+0x71a/0x9c4 preempt_schedule_irq+0xa0/0xe0 common_exception_return+0x5c/0x93 do_wp_page+0x30e/0x330 handle_mm_fault+0xa70/0xc3c do_page_fault+0x1d8/0x3c4 common_exception+0x7f/0x7f WARNING: CPU: 0 PID: 101 at mm/highmem.c:664 __kmap_local_sched_in+0x50/0xe0 CPU: 0 PID: 101 Comm: touch Tainted: G W 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13 Call Trace: dump_stack+0xc/0x40 __warn+0x8f/0x174 warn_slowpath_fmt+0x48/0xac __kmap_local_sched_in+0x50/0xe0 finish_task_switch$isra$0+0x1ce/0x2f8 __schedule+0x86e/0x9c4 preempt_schedule_irq+0xa0/0xe0 common_exception_return+0x5c/0x93 do_wp_page+0x30e/0x330 handle_mm_fault+0xa70/0xc3c do_page_fault+0x1d8/0x3c4 common_exception+0x7f/0x7f Fix it by replacing !pte_none(pteval) with pte_val(pteval) != 0.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5fbda3ecd14a5343644979c98d6eb65b7e7de9d8 , < c21d040de6225414547d9bd31cd200f290991c85 (git)
Affected: 5fbda3ecd14a5343644979c98d6eb65b7e7de9d8 , < 85550b0f5fa5dd3c30469ea702c44444ef242c83 (git)
Affected: 5fbda3ecd14a5343644979c98d6eb65b7e7de9d8 , < 7dd5b3b97716a611fcf67d92fd2370fcb8d50372 (git)
Affected: 5fbda3ecd14a5343644979c98d6eb65b7e7de9d8 , < 66f133ceab7456c789f70a242991ed1b27ba1c3d (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.11
Unaffected: 0 , < 5.11 (semver)
Unaffected: 5.15.34 , ≤ 5.15.* (semver)
Unaffected: 5.16.20 , ≤ 5.16.* (semver)
Unaffected: 5.17.3 , ≤ 5.17.* (semver)
Unaffected: 5.18 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhighmem: fix checks in __kmap_local_sched_{in,out}\n\nWhen CONFIG_DEBUG_KMAP_LOCAL is enabled __kmap_local_sched_{in,out} check\nthat even slots in the tsk-\u003ekmap_ctrl.pteval are unmapped.  The slots are\ninitialized with 0 value, but the check is done with pte_none.  0 pte\nhowever does not necessarily mean that pte_none will return true.  e.g.\non xtensa it returns false, resulting in the following runtime warnings:\n\n WARNING: CPU: 0 PID: 101 at mm/highmem.c:627 __kmap_local_sched_out+0x51/0x108\n CPU: 0 PID: 101 Comm: touch Not tainted 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13\n Call Trace:\n   dump_stack+0xc/0x40\n   __warn+0x8f/0x174\n   warn_slowpath_fmt+0x48/0xac\n   __kmap_local_sched_out+0x51/0x108\n   __schedule+0x71a/0x9c4\n   preempt_schedule_irq+0xa0/0xe0\n   common_exception_return+0x5c/0x93\n   do_wp_page+0x30e/0x330\n   handle_mm_fault+0xa70/0xc3c\n   do_page_fault+0x1d8/0x3c4\n   common_exception+0x7f/0x7f\n\n WARNING: CPU: 0 PID: 101 at mm/highmem.c:664 __kmap_local_sched_in+0x50/0xe0\n CPU: 0 PID: 101 Comm: touch Tainted: G        W         5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13\n Call Trace:\n   dump_stack+0xc/0x40\n   __warn+0x8f/0x174\n   warn_slowpath_fmt+0x48/0xac\n   __kmap_local_sched_in+0x50/0xe0\n   finish_task_switch$isra$0+0x1ce/0x2f8\n   __schedule+0x86e/0x9c4\n   preempt_schedule_irq+0xa0/0xe0\n   common_exception_return+0x5c/0x93\n   do_wp_page+0x30e/0x330\n   handle_mm_fault+0xa70/0xc3c\n   do_page_fault+0x1d8/0x3c4\n   common_exception+0x7f/0x7f\n\nFix it by replacing !pte_none(pteval) with pte_val(pteval) != 0."
        }
      ],
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        "dateUpdated": "2026-05-11T18:52:39.819Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/c21d040de6225414547d9bd31cd200f290991c85"
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          "url": "https://git.kernel.org/stable/c/85550b0f5fa5dd3c30469ea702c44444ef242c83"
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          "url": "https://git.kernel.org/stable/c/7dd5b3b97716a611fcf67d92fd2370fcb8d50372"
        },
        {
          "url": "https://git.kernel.org/stable/c/66f133ceab7456c789f70a242991ed1b27ba1c3d"
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    "cveId": "CVE-2022-49081",
    "datePublished": "2025-02-26T01:54:41.639Z",
    "dateReserved": "2025-02-26T01:49:39.247Z",
    "dateUpdated": "2026-05-11T18:52:39.819Z",
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      "date": "2026-09-17",
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    "nvd": "{\"cve\":{\"id\":\"CVE-2022-49081\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-02-26T07:00:45.450\",\"lastModified\":\"2026-06-17T05:17:01.663\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nhighmem: fix checks in __kmap_local_sched_{in,out}\\n\\nWhen CONFIG_DEBUG_KMAP_LOCAL is enabled __kmap_local_sched_{in,out} check\\nthat even slots in the tsk-\u003ekmap_ctrl.pteval are unmapped.  The slots are\\ninitialized with 0 value, but the check is done with pte_none.  0 pte\\nhowever does not necessarily mean that pte_none will return true.  e.g.\\non xtensa it returns false, resulting in the following runtime warnings:\\n\\n WARNING: CPU: 0 PID: 101 at mm/highmem.c:627 __kmap_local_sched_out+0x51/0x108\\n CPU: 0 PID: 101 Comm: touch Not tainted 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13\\n Call Trace:\\n   dump_stack+0xc/0x40\\n   __warn+0x8f/0x174\\n   warn_slowpath_fmt+0x48/0xac\\n   __kmap_local_sched_out+0x51/0x108\\n   __schedule+0x71a/0x9c4\\n   preempt_schedule_irq+0xa0/0xe0\\n   common_exception_return+0x5c/0x93\\n   do_wp_page+0x30e/0x330\\n   handle_mm_fault+0xa70/0xc3c\\n   do_page_fault+0x1d8/0x3c4\\n   common_exception+0x7f/0x7f\\n\\n WARNING: CPU: 0 PID: 101 at mm/highmem.c:664 __kmap_local_sched_in+0x50/0xe0\\n CPU: 0 PID: 101 Comm: touch Tainted: G        W         5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13\\n Call Trace:\\n   dump_stack+0xc/0x40\\n   __warn+0x8f/0x174\\n   warn_slowpath_fmt+0x48/0xac\\n   __kmap_local_sched_in+0x50/0xe0\\n   finish_task_switch$isra$0+0x1ce/0x2f8\\n   __schedule+0x86e/0x9c4\\n   preempt_schedule_irq+0xa0/0xe0\\n   common_exception_return+0x5c/0x93\\n   do_wp_page+0x30e/0x330\\n   handle_mm_fault+0xa70/0xc3c\\n   do_page_fault+0x1d8/0x3c4\\n   common_exception+0x7f/0x7f\\n\\nFix it by replacing !pte_none(pteval) with pte_val(pteval) != 0.\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: highmem: se corrigen las comprobaciones en __kmap_local_sched_{in,out}. Cuando CONFIG_DEBUG_KMAP_LOCAL est\u00e1 habilitado, __kmap_local_sched_{in,out} comprueba que ni siquiera las ranuras en tsk-\u0026gt;kmap_ctrl.pteval est\u00e9n asignadas. Las ranuras se inicializan con el valor 0, pero la comprobaci\u00f3n se realiza con pte_none. Sin embargo, 0 pte no significa necesariamente que pte_none devuelva verdadero. p. ej. en xtensa devuelve falso, lo que genera las siguientes advertencias de tiempo de ejecuci\u00f3n: ADVERTENCIA: CPU: 0 PID: 101 en mm/highmem.c:627 __kmap_local_sched_out+0x51/0x108 CPU: 0 PID: 101 Comm: touch No contaminado 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13 Seguimiento de llamadas: dump_stack+0xc/0x40 __warn+0x8f/0x174 warn_slowpath_fmt+0x48/0xac __kmap_local_sched_out+0x51/0x108 __schedule+0x71a/0x9c4 preempt_schedule_irq+0xa0/0xe0 common_exception_return+0x5c/0x93 do_wp_page+0x30e/0x330 handle_mm_fault+0xa70/0xc3c do_page_fault+0x1d8/0x3c4 common_exception+0x7f/0x7f ADVERTENCIA: CPU: 0 PID: 101 en mm/highmem.c:664 __kmap_local_sched_in+0x50/0xe0 CPU: 0 PID: 101 Comm: toque Contaminado: GW 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13 Seguimiento de llamadas: dump_stack+0xc/0x40 __warn+0x8f/0x174 warn_slowpath_fmt+0x48/0xac __kmap_local_sched_in+0x50/0xe0 Soluci\u00f3nelo reemplazando !pte_none(pteval) con pte_val(pteval) != 0.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"mm/highmem.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5fbda3ecd14a5343644979c98d6eb65b7e7de9d8\",\"lessThan\":\"c21d040de6225414547d9bd31cd200f290991c85\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5fbda3ecd14a5343644979c98d6eb65b7e7de9d8\",\"lessThan\":\"85550b0f5fa5dd3c30469ea702c44444ef242c83\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5fbda3ecd14a5343644979c98d6eb65b7e7de9d8\",\"lessThan\":\"7dd5b3b97716a611fcf67d92fd2370fcb8d50372\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5fbda3ecd14a5343644979c98d6eb65b7e7de9d8\",\"lessThan\":\"66f133ceab7456c789f70a242991ed1b27ba1c3d\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"mm/highmem.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.11\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.11\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.34\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.16.20\",\"lessThanOrEqual\":\"5.16.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.17.3\",\"lessThanOrEqual\":\"5.17.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.18\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"NVD-CWE-noinfo\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.15.34\",\"matchCriteriaId\":\"D25878D3-7761-4E9F-8919-E92CD53896E0\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"5.16.20\",\"matchCriteriaId\":\"ABBBA66E-0244-4621-966B-9790AF1EEB00\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.17\",\"versionEndExcluding\":\"5.17.3\",\"matchCriteriaId\":\"AE420AC7-1E59-4398-B84F-71F4B4337762\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.18:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"6AD94161-84BB-42E6-9882-4FC0C42E9FC1\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/66f133ceab7456c789f70a242991ed1b27ba1c3d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/7dd5b3b97716a611fcf67d92fd2370fcb8d50372\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/85550b0f5fa5dd3c30469ea702c44444ef242c83\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/c21d040de6225414547d9bd31cd200f290991c85\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-06-30T10:39:20+00:00",
      "cve": "CVE-2022-49081",
      "id": "CVE-2022-49081",
      "initial_release_date": "2022-01-01T00:00:00+00:00",
      "product_status:fixed": "321",
      "product_status:known_affected": "80",
      "product_status:known_not_affected": "76",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: highmem: fix checks in __kmap_local_sched_{in,out}",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2022/cve-2022-49081.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-03T16:59:53Z",
      "cve": "CVE-2022-49081",
      "id": "CVE-2022-49081",
      "initial_release_date": "2025-02-27T03:12:34Z",
      "product_status:known_affected": "128",
      "product_status:known_not_affected": "341",
      "product_status:recommended": "47",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2022-49081",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2022-49081.json",
      "version": "19"
    }
  }
}



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