cifs: prevent bad output lengths in smb2_ioctl_query_info()

{
  "id": "a49602d3c4ca39d1d98ae137f1ab2b0d91d596e5aea60b6ba24e1fff01b81e43",
  "url": "https://osv.dev/vulnerability/CVE-2022-49271",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "cifs: prevent bad output lengths in smb2_ioctl_query_info()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: cifs: prevent bad output lengths in smb2_ioctl_query_info() When calling smb2_ioctl_query_info() with smb_query_info::flags=PASSTHRU_FSCTL and smb_query_info::output_buffer_length=0, the following would return 0x10 buffer = memdup_user(arg + sizeof(struct smb_query_info), qi.output_buffer_length); if (IS_ERR(buffer)) { kfree(vars); return PTR_ERR(buffer); } rather than a valid pointer thus making IS_ERR() check fail. This would then cause a NULL ptr deference in @buffer when accessing it later in smb2_ioctl_query_ioctl(). While at it, prevent having a @buffer smaller than 8 bytes to correctly handle SMB2_SET_INFO FileEndOfFileInformation requests when smb_query_info::flags=PASSTHRU_SET_INFO. Here is a small C reproducer which triggers a NULL ptr in @buffer when passing an invalid smb_query_info::flags #include #include #include #include #include #include #define die(s) perror(s), exit(1) #define QUERY_INFO 0xc018cf07 int main(int argc, char *argv[]) { int fd; if (argc < 2) exit(1); fd = open(argv[1], O_RDONLY); if (fd == -1) die(\"open\"); if (ioctl(fd, QUERY_INFO, (uint32_t[]) { 0, 0, 0, 4, 0, 0}) == -1) die(\"ioctl\"); close(fd); return 0; } mount.cifs //srv/share /mnt -o ... gcc repro.c && ./a.out /mnt/f0 [ 114.138620] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 114.139310] KASAN: null-ptr-deref in range [0x0000000000000000-0x000000000000",
    "evidence": "osv:CVE-2022-49271",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.10.110",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.33",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.16.19",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.17.2",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2022-49271",
      "aliases": [
        "CVE-2022-49271"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "cfaa1181097f6a1a6f4f6670ebc97848efda0883"
                },
                {
                  "fixed": "9963ccea6087268e1275b992dca5d0dd4b938765"
                },
                {
                  "fixed": "f143f8334fb9eb2f6c7c15b9da1472d9c965fd84"
                },
                {
                  "fixed": "fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53"
                },
                {
                  "fixed": "7529fbee10d82493c5cb109e51788bf74816d1c0"
                },
                {
                  "fixed": "b92e358757b91c2827af112cae9af513f26a3f34"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49271.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.5.0"
                },
                {
                  "fixed": "5.10.110"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.11.0"
                },
                {
                  "fixed": "5.15.33"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "5.16.19"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.17.0"
                },
                {
                  "fixed": "5.17.2"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49271.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:35.917618221Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/7529fbee10d82493c5cb109e51788bf74816d1c0",
        "https://git.kernel.org/stable/c/9963ccea6087268e1275b992dca5d0dd4b938765",
        "https://git.kernel.org/stable/c/b92e358757b91c2827af112cae9af513f26a3f34",
        "https://git.kernel.org/stable/c/f143f8334fb9eb2f6c7c15b9da1472d9c965fd84",
        "https://git.kernel.org/stable/c/fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49271.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2022-49271",
        "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-2022-49271.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2022-49271",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 503113,
  "published_at": "2025-02-26T01:56:18.148+00:00"
}