hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()

{
  "id": "65068a05ea230f881947bca7c51273b0cbb397c8f33e435e42eea3f5b9482ec3",
  "url": "https://osv.dev/vulnerability/CVE-2022-50334",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param() Syzkaller reports a null-ptr-deref bug as follows: ====================================================== KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380 [...] Call Trace: vfs_parse_fs_param fs/fs_context.c:148 [inline] vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129 vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191 generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231 do_new_mount fs/namespace.c:3036 [inline] path_mount+0x12de/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] ====================================================== According to commit \"vfs: parse: deal with zero length string value\", kernel will set the param->string to null pointer in vfs_parse_fs_string() if fs string has zero length. Yet the problem is that, hugetlbfs_parse_param() will dereference the param->string, without checking whether it is a null pointer. To be more specific, if hugetlbfs_parse_param() parses an illegal mount parameter, such as \"size=,\", kernel will constructs struct ",
    "evidence": "osv:CVE-2022-50334",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.4.229",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.10.163",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.86",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.0.16",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.2",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2022-50334",
      "aliases": [
        "CVE-2022-50334"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "32021982a324dce93b4ae00c06213bf45fb319c8"
                },
                {
                  "fixed": "fa71639873518e3587632ae58e25e4a96b57fa90"
                },
                {
                  "fixed": "dcd28191be9bbf307ba51a5b485773a55b0037c4"
                },
                {
                  "fixed": "9a8862820cbf1f18dca4f3b4c289d88561b3a384"
                },
                {
                  "fixed": "965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd"
                },
                {
                  "fixed": "f2207145693ae5697a7b59e2add4b92f9e5b0e3c"
                },
                {
                  "fixed": "26215b7ee923b9251f7bb12c4e5f09dc465d35f2"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-50334.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.1.0"
                },
                {
                  "fixed": "5.4.229"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.5.0"
                },
                {
                  "fixed": "5.10.163"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.11.0"
                },
                {
                  "fixed": "5.15.86"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.0.16"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.1.0"
                },
                {
                  "fixed": "6.1.2"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-50334.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:35.113789098Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/26215b7ee923b9251f7bb12c4e5f09dc465d35f2",
        "https://git.kernel.org/stable/c/965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd",
        "https://git.kernel.org/stable/c/9a8862820cbf1f18dca4f3b4c289d88561b3a384",
        "https://git.kernel.org/stable/c/dcd28191be9bbf307ba51a5b485773a55b0037c4",
        "https://git.kernel.org/stable/c/f2207145693ae5697a7b59e2add4b92f9e5b0e3c",
        "https://git.kernel.org/stable/c/fa71639873518e3587632ae58e25e4a96b57fa90",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50334.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2022-50334",
        "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/2022/50xxx/CVE-2022-50334.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2022-50334",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 502216,
  "published_at": "2025-09-15T14:49:48.608+00:00"
}