CVE-2026-64257

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

smb: client: reject overlapping data areas in SMB2 responses

Commit 53b7c271f06b ("smb: client: restrict implied bcc[0] exemption to

responses without data area") restricted the implied bcc[0] length

exception to responses without a data area. However, the overlap

handling in __smb2_calc_size() clears data_length, which can make an

invalid response appear to have no data area and so qualify for the

exception.

Track data area overlap separately and reject such responses before

applying the length compatibility exceptions.