{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/f2fs/checkpoint.c",
            "fs/f2fs/f2fs.h",
            "fs/f2fs/super.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d7acf0a6c87aa282c86a36dbaa2f92fda88c5884",
              "status": "affected",
              "version": "af033b2aa8a874fd5737fafe90d159136527b5b4",
              "versionType": "git"
            },
            {
              "lessThan": "eb85c2410d6f581e957cd03a644ff6ddbe592af9",
              "status": "affected",
              "version": "af033b2aa8a874fd5737fafe90d159136527b5b4",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/f2fs/checkpoint.c",
            "fs/f2fs/f2fs.h",
            "fs/f2fs/super.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.20"
            },
            {
              "lessThan": "4.20",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.14.*",
              "status": "unaffected",
              "version": "6.14.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.15",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.14.2",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.15",
                  "versionStartIncluding": "4.20",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: quota: fix to avoid warning in dquot_writeback_dquots()\n\nF2FS-fs (dm-59): checkpoint=enable has some unwritten data.\n\n------------[ cut here ]------------\nWARNING: CPU: 6 PID: 8013 at fs/quota/dquot.c:691 dquot_writeback_dquots+0x2fc/0x308\npc : dquot_writeback_dquots+0x2fc/0x308\nlr : f2fs_quota_sync+0xcc/0x1c4\nCall trace:\ndquot_writeback_dquots+0x2fc/0x308\nf2fs_quota_sync+0xcc/0x1c4\nf2fs_write_checkpoint+0x3d4/0x9b0\nf2fs_issue_checkpoint+0x1bc/0x2c0\nf2fs_sync_fs+0x54/0x150\nf2fs_do_sync_file+0x2f8/0x814\n__f2fs_ioctl+0x1960/0x3244\nf2fs_ioctl+0x54/0xe0\n__arm64_sys_ioctl+0xa8/0xe4\ninvoke_syscall+0x58/0x114\n\ncheckpoint and f2fs_remount may race as below, resulting triggering warning\nin dquot_writeback_dquots().\n\natomic write                                    remount\n                                                - do_remount\n                                                 - down_write(\u0026sb-\u003es_umount);\n                                                  - f2fs_remount\n- ioctl\n - f2fs_do_sync_file\n  - f2fs_sync_fs\n   - f2fs_write_checkpoint\n    - block_operations\n     - locked = down_read_trylock(\u0026sbi-\u003esb-\u003es_umount)\n       : fail to lock due to the write lock was held by remount\n                                                 - up_write(\u0026sb-\u003es_umount);\n     - f2fs_quota_sync\n      - dquot_writeback_dquots\n       - WARN_ON_ONCE(!rwsem_is_locked(\u0026sb-\u003es_umount))\n       : trigger warning because s_umount lock was unlocked by remount\n\nIf checkpoint comes from mount/umount/remount/freeze/quotactl, caller of\ncheckpoint has already held s_umount lock, calling dquot_writeback_dquots()\nin the context should be safe.\n\nSo let\u0027s record task to sbi-\u003eumount_lock_holder, so that checkpoint can\nknow whether the lock has held in the context or not by checking current\nw/ it.\n\nIn addition, in order to not misrepresent caller of checkpoint, we should\nnot allow to trigger async checkpoint for those callers: mount/umount/remount/\nfreeze/quotactl."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerable path is entered purely through local syscalls against a mounted f2fs volume \u2014 `syncfs()`, `fsync()` or `__f2fs_ioctl()` reaching `f2fs_sync_fs` \u2192 `f2fs_issue_checkpoint` \u2192 `block_operations`. There is no remote or network-facing route into f2fs checkpointing.\nAC:H - The attacker can spam the checkpoint side at will, but `down_read_trylock(\u0026sb-\u003es_umount)` only fails while a *writer* holds the lock, and every writer (mount/remount/umount/freeze/quotaon-off/shutdown ioctl) is a CAP_SYS_ADMIN operation the unprivileged attacker cannot initiate; the lock must additionally be released or be tearing down quota within the narrow window before `dquot_writeback_dquots()`. That timing dependency on an administrative mount-state change is beyond the attacker\u0027s control.\nPR:L - The attacker-facing half needs no privilege at all \u2014 any local user with a file or fd on the f2fs mount can loop on `syncfs()`/`fsync()` to drive checkpoints, which is the case on every Android device where `/data` is f2fs with the `quota_ino` feature enabled by default. No capability, and no user namespace, is required on the triggering path.\nUI:N - The attacker issues the triggering syscall themselves and nothing must be opened, mounted or clicked on their behalf. The concurrent administrative remount is a timing precondition already accounted for in Attack Complexity, not victim participation in the attack.\nS:U - The damage is confined to kernel memory and kernel-managed quota/filesystem state within the same security authority. No hypervisor, IOMMU or sandbox boundary is crossed.\nC:H - Running `dquot_writeback_dquots()`/`f2fs_quota_sync_file()` without `s_umount` removes exactly the protection that keeps quota state alive \u2014 `dqopt-\u003efiles[type]-\u003ei_mapping` is dereferenced after only a lockless `sb_has_quota_active()` check, and `dqopt-\u003einfo[cnt].dqi_dirty_list` is walked while `invalidate_dquots()` frees its entries. A use-after-free read of `struct inode`/`struct dquot` in a general-purpose slab is leverageable for disclosure of adjacent kernel objects.\nI:H - The same unsynchronized window lets `filemap_fdatawrite()` and `dquot_write_dquot()` write through a quota inode that `vfs_cleanup_quota_inode()` has already `iput()`ed and NULLed, giving a write into freed slab memory alongside corruption of on-disk quota accounting (f2fs flags `SBI_QUOTA_NEED_REPAIR`, requiring fsck). A use-after-free write is a classic route to control-flow hijack.\nA:H - The immediate, reported effect is a `WARNING` splat that taints the kernel and is an outright panic on the many hardened Android, cloud and embedded builds that set `panic_on_warn=1`. Beyond that, the lost lock readily oopses the kernel via NULL dereference of a cleared `dqopt-\u003efiles[type]` or a use-after-free on the quota inode."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:56:58.643Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/d7acf0a6c87aa282c86a36dbaa2f92fda88c5884"
        },
        {
          "url": "https://git.kernel.org/stable/c/eb85c2410d6f581e957cd03a644ff6ddbe592af9"
        }
      ],
      "title": "f2fs: quota: fix to avoid warning in dquot_writeback_dquots()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-23132",
    "datePublished": "2025-04-16T14:13:13.697Z",
    "dateReserved": "2025-01-11T14:28:41.511Z",
    "dateUpdated": "2026-08-05T11:56:58.643Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}