CVE-2026-98681 PUBLISHED

smb: client: split cifsFileInfo bitfields to avoid shared-byte RMW races

Assigner: Linux
Reserved: 25.09.2026 Published: 18.10.2026 Updated: 18.10.2026

In the Linux kernel, the following vulnerability has been resolved:

smb: client: split cifsFileInfo bitfields to avoid shared-byte RMW races

The invalidHandle, swapfile, oplock_break_cancelled, offload, and status_file_deleted fields are stored in the same bitfield byte in struct cifsFileInfo, but are updated in different code paths that may run simultaneously, and are protected by different locks. Since bitfield assignments generate byte-level read-modify-write operations, a modification to one flag can overwrite a concurrent modification to another flag.

To avoid these races, convert these flags from a bitfield to separate bool fields.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 3bc303c254335dbd7c7012cc1760b12f1d5514d3 to 3786ee67658a2c80fef2544e7de2cd329e043cf9 (excl.)
  • affected from 3bc303c254335dbd7c7012cc1760b12f1d5514d3 to 4165641d06ef44f3a31b77a28048b6c737e885e7 (excl.)
  • affected from 3bc303c254335dbd7c7012cc1760b12f1d5514d3 to d9d23d115610e0342e768f6cb525d91c7b154027 (excl.)
  • affected from 3bc303c254335dbd7c7012cc1760b12f1d5514d3 to 19465a9aeb664f1d710d0d22c07c31bfb7c85446 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 2.6.32 is affected
  • unaffected from 0 to 2.6.32 (excl.)
  • unaffected from 6.12.113 to 6.12.* (incl.)
  • unaffected from 6.18.56 to 6.18.* (incl.)
  • unaffected from 7.2.10 to 7.2.* (incl.)
  • unaffected from 7.3-rc6 to * (incl.)

References