linux — security advisory

{
  "id": "1a83cb26aed5697dba5f1bc82d99ff1bae3151015fc8a770f3ab4333e8148945",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-47638",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2021-47638",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: ubifs: rename_whiteout: Fix double free for whiteout_ui->data 'whiteout_ui->data' will be freed twice if space budget fail for rename whiteout operation as following process: rename_whiteout dev = kmalloc whiteout_ui->data = dev kfree(whiteout_ui->data) // Free first time iput(whiteout) ubifs_free_inode kfree(ui->data) // Double free! KASAN reports: ================================================================== BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70 Call Trace: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f Allocated by task 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 Freed by task 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8 ================================================================== Let ubifs_free_inode() free 'whiteout_ui->data'. BTW, delete unused assignment 'whiteout_ui->data_len = 0', process 'ubifs_evict_inode() -> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode()' doesn't need it (because 'inc_nlink(whiteout)' won't be excuted by 'goto out_release', and the nlink of whiteout inode is 0).",
    "evidence": "osv:DEBIAN-CVE-2021-47638",
    "products": [
      {
        "name": {
          "value": "linux",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.17.3-1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "linux",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.17.3-1",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "linux",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.17.3-1",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "DEBIAN-CVE-2021-47638",
      "aliases": [
        "DEBIAN-CVE-2021-47638"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "5.17.3-1"
                }
              ]
            }
          ],
          "package": {
            "name": "linux",
            "purl": "pkg:deb/debian/linux?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47638.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "5.17.3-1"
                }
              ]
            }
          ],
          "package": {
            "name": "linux",
            "purl": "pkg:deb/debian/linux?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47638.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "5.17.3-1"
                }
              ]
            }
          ],
          "package": {
            "name": "linux",
            "purl": "pkg:deb/debian/linux?arch=source&distro=forky",
            "ecosystem": "Debian:14"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47638.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-23T18:04:21.048729653Z",
      "provider": "osv",
      "upstream": [
        "CVE-2021-47638"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2021-47638"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2021-47638",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 423535,
  "published_at": "2025-02-26T06:37:05.58+00:00"
}