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CVE PROGRAM SOURCE RECORDUnscored

CVE-2026-89644

btrfs: fix extent map leak in NOCOW direct I/O write

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Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix extent map leak in NOCOW direct I/O write btrfs_dio_iomap_begin() calls btrfs_get_extent(), which returns an extent map reference that must be dropped on all exit paths. For direct writes into a NOCOW range, btrfs_get_blocks_direct_write() keeps using that extent map and asks btrfs_create_dio_extent() to allocate the ordered extent. If that fails, for example because btrfs_alloc_ordered_extent() fails, the function returns the error without dropping the input extent map. The PREALLOC path avoided this by dropping the input extent map before replacing it with the newly created one. Check the error from btrfs_create_dio_extent() before replacing the map and drop the input extent map on failure.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 5f9a8a51d8b95505d8de8b7191ae2ed8c504d4af to < cb732d302245b14943a5017015fffa8e6db7a6c0affected
  • 5f9a8a51d8b95505d8de8b7191ae2ed8c504d4af to < b7c873765875645b11503f94c9bae2ca80127375affected
  • 5f9a8a51d8b95505d8de8b7191ae2ed8c504d4af to < f42efd634c0ae7ba0ce2fc5e30e291b0803b0ae2affected
  • 5f9a8a51d8b95505d8de8b7191ae2ed8c504d4af to < 05a1a816eef8b3e4332620a64fc8cf45c4eb5c0daffected
  • 5f9a8a51d8b95505d8de8b7191ae2ed8c504d4af to < 3f950867c307c5413d628a153ac44915bd117ffdaffected

Linux Linux

Default version status: affected

  • 4.7affected
  • 0 to < 4.7unaffected
  • 6.6.160 to ≤ 6.6.*unaffected
  • 6.12.111 to ≤ 6.12.*unaffected
  • 6.18.50 to ≤ 6.18.*unaffected
  • 7.2.4 to ≤ 7.2.*unaffected
  • 7.3 to ≤ *unaffected

References