{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "13bb483d32abb6f8ebd40141d87eb68f11cc2dd2"
            },
            {
              "fixed": "18577e77c2c8adaadf1f7c6e9bcd1c0b14e5dcdd"
            },
            {
              "fixed": "c3320873e0c04ce7b746fc8fe948f07bbbbdec33"
            },
            {
              "fixed": "deddd28fd83c264ee2ff5cd6b34449a9f1be6112"
            },
            {
              "fixed": "75859a7cd77cd2ddaddbcb963e3fcd34738953af"
            },
            {
              "fixed": "1ebe51c29fa9755d5b2fea28727c051117907cf8"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "fca3a1cd3ba47f1815e0c0fcdc9aafaf02ee0a75"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.5.5"
            },
            {
              "fixed": "6.6"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.6.0"
            },
            {
              "fixed": "6.6.151"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.103"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.44"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74572.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: zoned: fix deadlock between metadata writeback and transaction commit\n\nWhen writing out metadata extent buffers in a zoned filesystem,\nbtree_writepages() holds fs_info-\u003ezoned_meta_io_lock across the whole\nwriteback loop, including the call to btrfs_check_meta_write_pointer() -\u003e\ncheck_bg_is_active().\n\nFor the tree-log block group, check_bg_is_active() may fail to activate\nthe zone and fall back to btrfs_zone_finish_one_bg() to free an active\nzone. That path waits for the running transaction to commit while still\nholding zoned_meta_io_lock, but the committer needs that same lock to\nwrite out the tree extents, so the two tasks deadlock:\n\n  Task A (kworker, metadata writeback)      Task B (fsstress, transaction commit)\n  ------------------------------------      -------------------------------------\n  wb_workfn()                               btrfs_commit_transaction(T)\n   btree_writepages()                        btrfs_write_and_wait_transaction()\n    btrfs_zoned_meta_io_lock()                btrfs_write_marked_extents()\n    btrfs_check_meta_write_pointer()           btree_writepages()\n     check_bg_is_active() [treelog_bg]          btrfs_zoned_meta_io_lock()\n      btrfs_zone_finish_one_bg()               \u003cblocks on zoned_meta_io_lock,\n       btrfs_zone_finish()                      held by Task A\u003e\n        do_zone_finish()\n         btrfs_inc_block_group_ro()\n          btrfs_wait_for_commit()\n           \u003cblocks waiting for commit\n            of transaction T, done by\n            Task B\u003e\n\nThe sibling branch in check_bg_is_active() already drops zoned_meta_io_lock\naround do_zone_finish() for this exact reason. Do the same in the tree-log\nbranch: release the lock around btrfs_zone_finish_one_bg() and re-acquire\nit afterwards. The lock only protects fs_info-\u003eactive_{meta,system}_bg,\nwhich this branch does not touch, and ctx-\u003ezoned_bg keeps a reference to\nthe block group across the unlock, so nothing is lost while the lock\nis dropped.\n\nThis hang occasionally reproduces with fstests generic/475 on a zoned\nbtrfs filesystem.",
  "id": "CVE-2026-74572",
  "modified": "2026-08-18T03:31:11.118827704Z",
  "published": "2026-08-15T12:28:11.328Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/18577e77c2c8adaadf1f7c6e9bcd1c0b14e5dcdd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1ebe51c29fa9755d5b2fea28727c051117907cf8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/75859a7cd77cd2ddaddbcb963e3fcd34738953af"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c3320873e0c04ce7b746fc8fe948f07bbbbdec33"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/deddd28fd83c264ee2ff5cd6b34449a9f1be6112"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74572.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74572"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "btrfs: zoned: fix deadlock between metadata writeback and transaction commit"
}