btrfs: zoned: traverse devices under chunk_mutex in btrfs_can_activate_zone

{
  "id": "ec7694ea69cf2d79472192a7c154067dc62e6175cb06db180d27b2ba7f64c313",
  "url": "https://osv.dev/vulnerability/CVE-2022-49079",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "btrfs: zoned: traverse devices under chunk_mutex in btrfs_can_activate_zone",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: btrfs: zoned: traverse devices under chunk_mutex in btrfs_can_activate_zone btrfs_can_activate_zone() can be called with the device_list_mutex already held, which will lead to a deadlock: insert_dev_extents() // Takes device_list_mutex `-> insert_dev_extent() `-> btrfs_insert_empty_item() `-> btrfs_insert_empty_items() `-> btrfs_search_slot() `-> btrfs_cow_block() `-> __btrfs_cow_block() `-> btrfs_alloc_tree_block() `-> btrfs_reserve_extent() `-> find_free_extent() `-> find_free_extent_update_loop() `-> can_allocate_chunk() `-> btrfs_can_activate_zone() // Takes device_list_mutex again Instead of using the RCU on fs_devices->device_list we can use fs_devices->alloc_list, protected by the chunk_mutex to traverse the list of active devices. We are in the chunk allocation thread. The newer chunk allocation happens from the devices in the fs_device->alloc_list protected by the chunk_mutex. btrfs_create_chunk() lockdep_assert_held(&info->chunk_mutex); gather_device_info list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) Also, a device that reappears after the mount won't join the alloc_list yet and, it will be in the dev_list, which we don't want to consider in the context of the chunk alloc. [15.166572] WARNING: possible recursive locking detected [15.167117] 5.17.0-rc6-dennis #79 Not tainted [15.167487] -------------------------------------------- [15.167733] kworker/u8:3/146 is trying to acqui",
    "evidence": "osv:CVE-2022-49079",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.16.20",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.17.3",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2022-49079",
      "aliases": [
        "CVE-2022-49079"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "a85f05e59bc15a83ad910dbcb71df5ad8fa77295"
                },
                {
                  "fixed": "09e65ae515af2b24d6dc23af21719a3b41de83e5"
                },
                {
                  "fixed": "142f822bd945a7be442a2916ec6167cc102c4183"
                },
                {
                  "fixed": "0b9e66762aa0cda2a9c2d5542d64e04dac528fa6"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49079.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "5.16.20"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.17.0"
                },
                {
                  "fixed": "5.17.3"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49079.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:53.397027496Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/09e65ae515af2b24d6dc23af21719a3b41de83e5",
        "https://git.kernel.org/stable/c/0b9e66762aa0cda2a9c2d5542d64e04dac528fa6",
        "https://git.kernel.org/stable/c/142f822bd945a7be442a2916ec6167cc102c4183",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49079.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2022-49079",
        "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-2022-49079.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2022-49079",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 522024,
  "published_at": "2025-02-26T01:54:40.697+00:00"
}