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.
https://git.kernel.org/stable/c/d9d23d115610e0342e768f6cb525d91c7b154027
https://git.kernel.org/stable/c/4165641d06ef44f3a31b77a28048b6c737e885e7
https://git.kernel.org/stable/c/3786ee67658a2c80fef2544e7de2cd329e043cf9
https://git.kernel.org/stable/c/19465a9aeb664f1d710d0d22c07c31bfb7c85446