From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 95CF53E5EC3 for ; Sun, 18 Oct 2026 15:20:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792336831; cv=none; b=F1HWwmGHzI/5Ia4cwI1nH83XzssundGBWP6D3GzKxeuQIM5/emPcu1BXs6smgZmUD0FiYqiiiBO5n4O2bTfYRx1nMJLuINrQpATf1Mg1B39eEcJR9Ss8D182p3W8P+7Oqd+ajDJD2/CU2bXXfxdoxN2jOoz5oyTjrAI81V32Azg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792336831; c=relaxed/simple; bh=PFHn4q59OGAJkROnIWxL3UWF+bu+V7+PUec7/rX+GJc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=sYaGd4cfYtc8GZ+Ieqj8Erj1HkkTfcr5zCQpeWr0uhDSHW4L2EUm1ta0DmRvPANzAWQBX8HePdmiouwS4L/lPf7bwJNqlqF7u5s6IlvMWKk+4wyCxrmAc1UMOya1mxduLHam9B5OKDcJMlz60MAUQS1gcWTGMDloOUcnpKwUL5s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ZfkTpFmm; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ZfkTpFmm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B23FE1F000C4; Sun, 18 Oct 2026 15:20:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792336830; bh=vNcPJVrILylqXFJ0Z5YOKfZE2sguZx/d88tI9SpKzCA=; h=From:To:Cc:Subject:Date:Reply-To; b=ZfkTpFmmQYcO3kl53Iw11A+X7lqLpX5/iob/mX/iwUV8S99W4ZD5CK+Fkk+r72vRn jhF0aE0MeYU4RawIwX5hrz4+4whfSamANMMBY0W685sJp+zknlG0R/Uwlb0VSJvxHQ Uzo58850PPQ12gMnzi2M+/1kUT9xY/QoUgBFgAyg= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98472: KVM: SEV: Free have_run_cpus during VM destruction even if VM is no longer SEV Date: Sun, 18 Oct 2026 17:15:36 +0200 Message-ID: <2026101813-CVE-2026-98472-e917@gregkh> X-Mailer: git-send-email 2.56.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2803; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=bdH92ClXnkdCSI8OIYSCSBJe+/bVX+mK3yFDHDQHq4c=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlXHjW2BEWtnbTw9eTMUvtZG3P/96y7/u3ZJYE56l0uI l+sWhKZO2JZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAiRWcZFixseW9lNWGq8NeQ 1okHSjkFrikUejAsOKd8YHt/YrlcnaVkSvzrxdVSpzXSAQ== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Free have_run_cpus during VM destruction even if VM is no longer SEV Unconditionally free SEV's "have run CPUs" cpumask in the VM destroy path, i.e. even for what appear to be non-SEV VMs, as an SEV VM becomes a non-SEV VM if its state is intra-host migrated. Alternatively, the mask could be freed in sev_migrate_from() when "converting" the source VM, but that gets annoying because ideally KVM would nullify the mask to guard against UAF, and nullifying the mask would need be conditioned on CPUMASK_OFFSTACK=y. Freeing the mask during sev_migrate_from() is also not robust against other KVM bugs, though that's kind of a moot point since any such bugs would show up even if sev->active is never set. I.e. KVM must get that side of things correct. But, that's not a great reason to add more code just to make things marginally less robust. The Linux kernel CVE team has assigned CVE-2026-98472 to this issue. Affected and fixed versions =========================== Issue introduced in 6.17 with commit 6f38f8c574642a822f2e85f079fa29a49176c49c and fixed in 6.18.55 with commit 6aef7cf800098749ff5d660222efaf6e01e98c09 Issue introduced in 6.17 with commit 6f38f8c574642a822f2e85f079fa29a49176c49c and fixed in 7.2.9 with commit 9784e5ca91b37b387f3f414af4340c54f7a63566 Issue introduced in 6.17 with commit 6f38f8c574642a822f2e85f079fa29a49176c49c and fixed in 7.3-rc5 with commit 12c1f6e03f944e399bd2c88441dca5dc702b95a5 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-2026-98472 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: arch/x86/kvm/svm/sev.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/6aef7cf800098749ff5d660222efaf6e01e98c09 https://git.kernel.org/stable/c/9784e5ca91b37b387f3f414af4340c54f7a63566 https://git.kernel.org/stable/c/12c1f6e03f944e399bd2c88441dca5dc702b95a5