CVE-2026-64382: smb: client: fix double-free in SMB2_open() 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_open() replay

A response-bearing attempt can return a replayable error and free its
response buffer. If SMB2_open_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-2026-64382 to this issue.


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

	Issue introduced in 6.6.32 with commit 433042a91f9373241307725b52de573933ffedbf and fixed in 6.6.145 with commit 02bc2896bdc3e29362d6e40d404006944a159c25
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 6.12.96 with commit 3196b5192f246df4272072f61a2f4a3e9967f55d
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 6.18.39 with commit 14498ff5ce0f272ce0ef988721413e06b7038972
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 7.1.4 with commit ff2d30927bc3bf3c629f0768d2068096e64ef5ce
	Issue introduced in 6.8 with commit 4f1fffa2376922f3d1d506e49c0fd445b023a28e and fixed in 7.2-rc1 with commit b55e182f2324bc6a604c21a47aa6c448f719a532

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-2026-64382
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/02bc2896bdc3e29362d6e40d404006944a159c25
	https://git.kernel.org/stable/c/3196b5192f246df4272072f61a2f4a3e9967f55d
	https://git.kernel.org/stable/c/14498ff5ce0f272ce0ef988721413e06b7038972
	https://git.kernel.org/stable/c/ff2d30927bc3bf3c629f0768d2068096e64ef5ce
	https://git.kernel.org/stable/c/b55e182f2324bc6a604c21a47aa6c448f719a532