From patchwork Mon Aug 3 08:48:19 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Junjie Cao X-Patchwork-Id: 94287 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31482C55175 for ; Mon, 3 Aug 2026 08:49:28 +0000 (UTC) Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) by mx.groups.io with SMTP id smtpd.msgproc02-g2.39073.1785746967123020401 for ; Mon, 03 Aug 2026 01:49:27 -0700 Authentication-Results: mx.groups.io; dkim=fail reason="dkim: body hash did not verify" header.i=@linux.dev header.s=key1 header.b=vPphBxsT; spf=pass (domain: linux.dev, ip: 91.218.175.183, mailfrom: junjie.cao@linux.dev) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1785746964; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MtWIajyyFcxIT8xrpdsenwui+ADWAk0ntEAs7yee5Ds=; b=vPphBxsTGF/9K+A138CK3mX6wqeVgLGY69Ix8gpTED0qm/VI8w/sgLZTokhbnkwlMSG3QB NQ+7Wp/albL1cI1XITMfvJzrUNSkd87kVvzk2ZUuoAIKL3qrdGzGjV2mevFfKRHMCoxjPL smzqvRH1vuZbB1EdZa6ahIbmYcfN/w0= From: Junjie Cao To: openembedded-core@lists.openembedded.org Cc: paul@pbarker.dev, randy.macleod@windriver.com, Venkata.Navuduri@windriver.com Subject: [OE-core][PATCH v2 02/10] cve-exclusion: set status for CVE-2021-3714 Date: Mon, 3 Aug 2026 01:48:19 -0700 Message-ID: <20260803084827.1348810-3-junjie.cao@linux.dev> In-Reply-To: <20260803084827.1348810-1-junjie.cao@linux.dev> References: <20260803084827.1348810-1-junjie.cao@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT List-Id: X-Webhook-Received: from 45-33-107-173.ip.linodeusercontent.com [45.33.107.173] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Mon, 03 Aug 2026 08:49:28 -0000 X-Groupsio-URL: https://lists.openembedded.org/g/openembedded-core/message/242628 KSM merges identical anonymous pages across processes. An attacker who can place chosen page-sized content in a victim's memory can detect the merge through the timing of the resulting copy-on-write fault, and so leak memory contents remotely. This cannot be fixed without removing deduplication, and the affected projects have said so explicitly. Red Hat closed the issue WONTFIX: https://bugzilla.redhat.com/show_bug.cgi?id=1931327 Debian marks src:linux unfixed with the note "Inherent design limitation, can be avoided by not using KSM": https://security-tracker.debian.org/tracker/CVE-2021-3714 Ubuntu records "there is no upstream fix available as of 2024-06-17" and lists disabling KSM as the only mitigation: https://ubuntu.com/security/CVE-2021-3714 CONFIG_KSM=y is set in yocto-kernel-cache (bsp/intel-x86 and the paravirt_kvm fragments), so this is not a configuration exclusion. It does however require two runtime opt-ins: ksm_run defaults to KSM_RUN_STOP in mm/ksm.c, so ksmd must be started by the administrator, and memory is only eligible if the process asks for it with madvise(MADV_MERGEABLE) or prctl(PR_SET_MEMORY_MERGE). CC: Paul Barker AI-Generated: Uses Claude (claude-opus-5) Signed-off-by: Junjie Cao --- changes in v2: - split out of the single combined patch, one CVE per patch as requested - added primary source links (disclosures, distribution trackers, mailing list threads, upstream commits) to every commit message - added the three CVEs with no upstream fix as "unpatched" entries instead of leaving them undocumented - disclosed AI assistance per the contributor guide v1: https://lore.kernel.org/openembedded-core/20260802143444.1178575-1-junjie.cao@linux.dev/ meta/recipes-kernel/linux/cve-exclusion.inc | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/meta/recipes-kernel/linux/cve-exclusion.inc b/meta/recipes-kernel/linux/cve-exclusion.inc index aaba26fe..9012d328 100644 --- a/meta/recipes-kernel/linux/cve-exclusion.inc +++ b/meta/recipes-kernel/linux/cve-exclusion.inc @@ -199,3 +199,10 @@ CVE_STATUS[CVE-2025-71145] = "cpe-stable-backport: Fixed from v6.18.3" # https://www.openwall.com/lists/oss-security/2019/12/05/1 CVE_STATUS[CVE-2019-14899] = "upstream-wontfix: consequence of the default weak \ host model, no kernel fix exists or is planned, mitigated by firewall configuration" + +# Inherent to KSM deduplication, closed WONTFIX by Red Hat. Exposure needs +# ksmd started at runtime (/sys/kernel/mm/ksm/run defaults to 0) and the +# workload to opt in via MADV_MERGEABLE or prctl(PR_SET_MEMORY_MERGE). +# https://bugzilla.redhat.com/show_bug.cgi?id=1931327 +CVE_STATUS[CVE-2021-3714] = "upstream-wontfix: inherent design limitation of \ +KSM page deduplication, closed WONTFIX by Red Hat, no upstream fix planned"