{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.6-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  btrfs: balance: fix potential bg lookup failure in btrfs_may_alloc_data_chunk()  [BUG] Running btrfs balance can trigger a null-ptr-deref before relocating a data chunk when metadata corruption leaves a chunk in the chunk tree without a corresponding block group in the in-memory cache:    KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f]   RIP: 0010:btrfs_may_alloc_data_chunk+0x40/0x1c0 fs/btrfs/volumes.c:3601   Call Trace:     __btrfs_balance fs/btrfs/volumes.c:4217 [inline]     btrfs_balance+0x2516/0x42b0 fs/btrfs/volumes.c:4604     btrfs_ioctl_balance fs/btrfs/ioctl.c:3577 [inline]     btrfs_ioctl+0x25cf/0x5b90 fs/btrfs/ioctl.c:5313     ...  [CAUSE] __btrfs_balance() iterates the on-disk chunk tree and passes the chunk logical bytenr to btrfs_may_alloc_data_chunk() before relocating a data chunk. That helper then queries the in-memory block group cache:    cache = btrfs_lookup_block_group(fs_info, chunk_offset);   chunk_type = cache-\u003eflags;   /* cache may be NULL */  A corrupt image can contain a chunk item whose matching block group item is missing, so no block group is ever inserted into the cache. In that case btrfs_lookup_block_group() returns NULL.  The code only guards this with ASSERT(cache), which becomes a no-op when CONFIG_BTRFS_ASSERT is disabled. The subsequent dereference of cache-\u003eflags therefore crashes the kernel.  [FIX] Add a NULL check after btrfs_lookup_block_group() in btrfs_may_alloc_data_chunk() and print and error message for clarity.",
  "id": "DEBIAN-CVE-2026-97416",
  "modified": "2026-09-26T08:47:28.944335246Z",
  "published": "2026-09-24T17:17:19.340Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-97416"
    }
  ],
  "upstream": [
    "CVE-2026-97416"
  ]
}