CVE-2026-64385: smb: client: fix double-free in SMB2_ioctl() replay

From: Greg Kroah-Hartman <[email protected]>

Description
===========

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

smb: client: fix double-free in SMB2_ioctl() replay

A response-bearing attempt can return a replayable error and free its
response buffer. If SMB2_ioctl_init() fails before the next send, cleanup
retains the previous buffer type and frees that response again.

Reset response bookkeeping before each attempt to prevent the stale free.

The Linux kernel CVE team has assigned CVE-2026-64385 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.6.32 with commit 433042a91f9373241307725b52de573933ffedbf and fixed in 6.6.145 with commit 0be4bc64882edaefaaee8d1e27d083643eb778e6
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 6.12.96 with commit 96fcfc8ae7359346156e492ca610e830d2649ad6
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 6.18.39 with commit 276c8efbc49f9303ac76d0d4deab7128581b0f3b
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 7.1.4 with commit fc65ffb4ef1bf540da16b17c225ae51091e07d72
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 7.2-rc1 with commit f9bbadb6c94583e3b4af1afc449bfceb1d1ddec9

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-64385
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	fs/smb/client/smb2pdu.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/0be4bc64882edaefaaee8d1e27d083643eb778e6
	https://git.kernel.org/stable/c/96fcfc8ae7359346156e492ca610e830d2649ad6
	https://git.kernel.org/stable/c/276c8efbc49f9303ac76d0d4deab7128581b0f3b
	https://git.kernel.org/stable/c/fc65ffb4ef1bf540da16b17c225ae51091e07d72
	https://git.kernel.org/stable/c/f9bbadb6c94583e3b4af1afc449bfceb1d1ddec9