highmem: fix checks in __kmap_local_sched_{in,out}

{
  "id": "47c3c546a2d4bccb64d72d2927d24644cf61592e237b4e72a46b70634b7b13a3",
  "url": "https://osv.dev/vulnerability/CVE-2022-49081",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "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)",
    "evidence": "osv:CVE-2022-49081",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.34",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.16.20",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.17.3",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2022-49081",
      "aliases": [
        "CVE-2022-49081"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "5fbda3ecd14a5343644979c98d6eb65b7e7de9d8"
                },
                {
                  "fixed": "c21d040de6225414547d9bd31cd200f290991c85"
                },
                {
                  "fixed": "85550b0f5fa5dd3c30469ea702c44444ef242c83"
                },
                {
                  "fixed": "7dd5b3b97716a611fcf67d92fd2370fcb8d50372"
                },
                {
                  "fixed": "66f133ceab7456c789f70a242991ed1b27ba1c3d"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49081.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.11.0"
                },
                {
                  "fixed": "5.15.34"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "5.16.20"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.17.0"
                },
                {
                  "fixed": "5.17.3"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49081.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:43.784184532Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/66f133ceab7456c789f70a242991ed1b27ba1c3d",
        "https://git.kernel.org/stable/c/7dd5b3b97716a611fcf67d92fd2370fcb8d50372",
        "https://git.kernel.org/stable/c/85550b0f5fa5dd3c30469ea702c44444ef242c83",
        "https://git.kernel.org/stable/c/c21d040de6225414547d9bd31cd200f290991c85",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49081.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2022-49081",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49081.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2022-49081",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 511620,
  "published_at": "2025-02-26T01:54:41.639+00:00"
}