{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2025-71123",
  "modified": "2026-10-07T14:35:31Z",
  "upstream": [
    "CVE-2025-71123"
  ],
  "published": "2026-01-14T15:06:27Z",
  "summary": "ext4: fix string copying in parse_apply_sb_mount_options()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix string copying in parse_apply_sb_mount_options()\n\nstrscpy_pad() can't be used to copy a non-NUL-term string into a NUL-term\nstring of possibly bigger size.  Commit 0efc5990bca5 (\"string.h: Introduce\nmemtostr() and memtostr_pad()\") provides additional information in that\nregard.  So if this happens, the following warning is observed:\n\nstrnlen: detected buffer overflow: 65 byte read of buffer size 64\nWARNING: CPU: 0 PID: 28655 at lib/string_helpers.c:1032 __fortify_report+0x96/0xc0 lib/string_helpers.c:1032\nModules linked in:\nCPU: 0 UID: 0 PID: 28655 Comm: syz-executor.3 Not tainted 6.12.54-syzkaller-00144-g5f0270f1ba00 #0\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nRIP: 0010:__fortify_report+0x96/0xc0 lib/string_helpers.c:1032\nCall Trace:\n <TASK>\n __fortify_panic+0x1f/0x30 lib/string_helpers.c:1039\n strnlen include/linux/fortify-string.h:235 [inline]\n sized_strscpy include/linux/fortify-string.h:309 [inline]\n parse_apply_sb_mount_options fs/ext4/super.c:2504 [inline]\n __ext4_fill_super fs/ext4/super.c:5261 [inline]\n ext4_fill_super+0x3c35/0xad00 fs/ext4/super.c:5706\n get_tree_bdev_flags+0x387/0x620 fs/super.c:1636\n vfs_get_tree+0x93/0x380 fs/super.c:1814\n do_new_mount fs/namespace.c:3553 [inline]\n path_mount+0x6ae/0x1f70 fs/namespace.c:3880\n do_mount fs/namespace.c:3893 [inline]\n __do_sys_mount fs/namespace.c:4103 [inline]\n __se_sys_mount fs/namespace.c:4080 [inline]\n __x64_sys_mount+0x280/0x300 fs/namespace.c:4080\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x64/0x140 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nSince userspace is expected to provide s_mount_opts field to be at most 63\ncharacters long with the ending byte being NUL-term, use a 64-byte buffer\nwhich matches the size of s_mount_opts, so that strscpy_pad() does its job\nproperly.  Return with error if the user still managed to provide a\nnon-NUL-term string here.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.12.62-1+rpt1~bookworm"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-2712",
            "binary_version": "1:6.12.62-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v6",
            "binary_version": "1:6.12.62-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v7",
            "binary_version": "1:6.12.62-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v7l",
            "binary_version": "1:6.12.62-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v8",
            "binary_version": "1:6.12.62-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v8-rt",
            "binary_version": "1:6.12.62-1+rpt1~bookworm"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.12.62-1+rpt1~bookworm": {
            "linux_commit": "a1073743767f9e7fdc7017ababd2a07ea0c97c1c",
            "upstream_version": "6.12.62",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.64"
          }
        }
      }
    },
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:13",
        "name": "linux"
      },
      "versions": [
        "1:6.12.62-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-2712",
            "binary_version": "1:6.12.62-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v6",
            "binary_version": "1:6.12.62-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v7",
            "binary_version": "1:6.12.62-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v8",
            "binary_version": "1:6.12.62-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.62+rpt-rpi-v8-rt",
            "binary_version": "1:6.12.62-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.12.62-1+rpt1": {
            "linux_commit": "a1073743767f9e7fdc7017ababd2a07ea0c97c1c",
            "upstream_version": "6.12.62",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.64"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-71123"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/52ac96c4a2dd7bc47666000440b0602d9742e820"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6e37143560e37869d51b7d9e0ac61fc48895f8a0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/902ca2356f1e3ec5355c5808ad5d3f9d0095b0cc"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/db9ee13fab0267eccf6544ee35b16c9522db9aac"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5bbacbbf1ca4419861dca3c6b82707c10e9c021c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ee5a977b4e771cc181f39d504426dbd31ed701cc"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-05-24T06:48:58Z"
  }
}
