From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C1C9C361667 for ; Fri, 8 May 2026 14:24:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778250243; cv=none; b=bbKn//bYsl7+ar15YRuWMutk66T3CDUNW87sbXiWBVQfpu2JPcAfhGrMkC76j+ZpdXh/S++/Z9/Gd89c9KMhxc7Bk4ynU3KSC/caFuqKp9oZ0HCforw+Iv8d5B0Bv1k1qmY2twwE493d7AodfNpSm1izJYnhyrRnzNvtUU6Q5EU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778250243; c=relaxed/simple; bh=VgSU9XG/MCzifICL3RtmDjKH8iN6HfAiXQFQXYyVMM8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=fSLNPFK1jqqrOVRMGD5JTEX+ilJFWiBvehDMGisVYnu0pAZg86YJAmP9WP3mRfRXvU3/gIFuFf1sdthtmQf/P7nwmKamJ88sMg21OVo2nQ5v8WD+oYb3ThudpaKde6CXZZiQD699S4NnQzOGjr98s+GnAY5QFsJV5X6qTBU4OOc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=L4Vywb+l; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="L4Vywb+l" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58897C2BCB0; Fri, 8 May 2026 14:24:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778250243; bh=VgSU9XG/MCzifICL3RtmDjKH8iN6HfAiXQFQXYyVMM8=; h=From:To:Cc:Subject:Date:Reply-To:From; b=L4Vywb+l6FkslbIg+daROxVnZCEdEzk4ul6CCYu2iS0mJwasBAk9eYQAPGObYxtt3 zLUp8UCHEn/BAVnzSSXiPLajBy5lPsUTPYvPb6ZpL96c4+96FPdNIf5TlDRtrSyB+B wWqkLAOcvdopHPxHYewPXS1V5CDVg55BWZuljjyE= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-43401: cpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request() Date: Fri, 8 May 2026 16:22:10 +0200 Message-ID: <2026050840-CVE-2026-43401-c331@gregkh> X-Mailer: git-send-email 2.54.0 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=2836; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=4+nE8j66dEsr2e3cj79sqTb5xHx7kEB43fLle2/0FAY=; b=owGbwMvMwCRo6H6F97bub03G02pJDJl/P5ZI2CqtCvvjsy7r5Pmf5teLdddEHA2dsG7VjIgVC 2bwTpq8qSOWhUGQiUFWTJHlyzaeo/srDil6GdqehpnDygQyhIGLUwAmMiuPYZ6ZoXzwF/5Ftit3 cNjZbPx/7ND9vEUMc0UKX16/ahO3XMesZt0T9SdtGVMygwA= 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: cpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request() The update_cpu_qos_request() function attempts to initialize the 'freq' variable by dereferencing 'cpudata' before verifying if the 'policy' is valid. This issue occurs on systems booted with the "nosmt" parameter, where all_cpu_data[cpu] is NULL for the SMT sibling threads. As a result, any call to update_qos_requests() will result in a NULL pointer dereference as the code will attempt to access pstate.turbo_freq using the NULL cpudata pointer. Also, pstate.turbo_freq may be updated by intel_pstate_get_hwp_cap() after initializing the 'freq' variable, so it is better to defer the 'freq' until intel_pstate_get_hwp_cap() has been called. Fix this by deferring the 'freq' assignment until after the policy and driver_data have been validated. [ rjw: Added one paragraph to the changelog ] The Linux kernel CVE team has assigned CVE-2026-43401 to this issue. Affected and fixed versions =========================== Issue introduced in 6.18 with commit ae1bdd23b99f64335c69d546bff99ca39b894c18 and fixed in 6.18.19 with commit 6bfda7ce56e7d14a677b7bcd6c7a5009cc29aa88 Issue introduced in 6.18 with commit ae1bdd23b99f64335c69d546bff99ca39b894c18 and fixed in 6.19.9 with commit 42738dffb7b0766a45882dff7989401d78f66f92 Issue introduced in 6.18 with commit ae1bdd23b99f64335c69d546bff99ca39b894c18 and fixed in 7.0 with commit ab39cc4cb8ceecdc2b61747433e7237f1ac2b789 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-2026-43401 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: drivers/cpufreq/intel_pstate.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/6bfda7ce56e7d14a677b7bcd6c7a5009cc29aa88 https://git.kernel.org/stable/c/42738dffb7b0766a45882dff7989401d78f66f92 https://git.kernel.org/stable/c/ab39cc4cb8ceecdc2b61747433e7237f1ac2b789