CVE-2026-98453: smb: client: close handle after create-context parsing failure

CVE-2026-98453: smb: client: close handle after create-context parsing failure

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

smb: client: close handle after create-context parsing failure

SMB2_open() accounts a successful CREATE response as a remote open before
parsing its create contexts.  If smb2_parse_contexts() rejects malformed
context data, SMB2_open() returns without closing the handle, leaving the
server-side handle open and num_remote_opens elevated.

Close the handle after a post-CREATE context parsing failure so the error
path releases the remote resource and balances the open count.

The Linux kernel CVE team has assigned CVE-2026-98453 to this issue.


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

	Issue introduced in 6.7 with commit af1689a9b7701d9907dfc84d2a4b57c4bc907144 and fixed in 6.12.113 with commit 80c67cc71d32ccafc89a29b669243b40d81b930f
	Issue introduced in 6.7 with commit af1689a9b7701d9907dfc84d2a4b57c4bc907144 and fixed in 6.18.56 with commit f09875ff901e933e7b22c913daf51d21e9d93a45
	Issue introduced in 6.7 with commit af1689a9b7701d9907dfc84d2a4b57c4bc907144 and fixed in 7.2.9 with commit cdb36b09fb1f86d638d0afb44d621ed3f7c1d8eb
	Issue introduced in 6.7 with commit af1689a9b7701d9907dfc84d2a4b57c4bc907144 and fixed in 7.3-rc5 with commit 566820af017e81497fb5e9d3ad6e7ffe2828bc8b
	Issue introduced in 5.4.277 with commit 6726429c18c62dbf5e96ebbd522f262e016553fb
	Issue introduced in 5.10.211 with commit 13fb0fc4917621f3dfa285a27eaf7151d770b5e5
	Issue introduced in 5.15.150 with commit 890bc4fac3c0973a49cac35f634579bebba7fe48
	Issue introduced in 6.1.79 with commit 1ae3c59355dc9882e09c020afe8ffbd895ad0f29
	Issue introduced in 6.6.8 with commit 17a0f64cc02d4972e21c733d9f21d1c512963afa

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-2026-98453
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/80c67cc71d32ccafc89a29b669243b40d81b930f
	https://git.kernel.org/stable/c/f09875ff901e933e7b22c913daf51d21e9d93a45
	https://git.kernel.org/stable/c/cdb36b09fb1f86d638d0afb44d621ed3f7c1d8eb
	https://git.kernel.org/stable/c/566820af017e81497fb5e9d3ad6e7ffe2828bc8b