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 C953C470E96 for ; Sun, 18 Oct 2026 15:53:33 +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=1792338815; cv=none; b=UTlDpJaWDBDzAcu4RlZb1wK9A0mM7dnddyuGsJrRX5B2H0PRv6wyCo12laLq5aMw1cXN8v/G5WfwvdOMoRvLJClVHmTSk1PVr8qYAQOKzeqcDUbd583olUG6RopB++iMbga4f/4RvxusDbuJk7DxlflQLbWIOzU+TY9YSTL7IXA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792338815; c=relaxed/simple; bh=4kXx8Pndt1q5YQSomoVjuBbbkbd58Ua5ZfbCiOLXo50=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=rdNeXeG4ikFRHrPhYmwnmwT8BKderTl3+AGG317GeoUu43uhuNQvzG8EYqVOUe7abzRB+BtgfkGl84CVumvZR7h5KElsCEn9+QOD2d/WVf+7rFo6WXfo6MfXGKHZ8XW0+I0i3g/SEC3SrqpLA+Sae0Upf2UBU+VDFO0QAo3uHo8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Usx4FeAf; 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="Usx4FeAf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC5B21F000C4; Sun, 18 Oct 2026 15:53:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792338813; bh=9DX2ynk45lY4adhMfdaMv+68NQV1YKZTtO6Viwmyruk=; h=From:To:Cc:Subject:Date:Reply-To; b=Usx4FeAfFqpVj6dsGq1U/ujtmMhr70I8j1N/QCGZJ+Dn5e7mQkAMWN2yZkvLHX7xl C8XkZKf4ESNZfYxk10dWDLZfww9GZbT2WUIjNn6vyR9smiIhzCdYOmExBHU/RFO6Zo sKTk+GYtGzp9CVwrBw0zvj+r5T4/FdHGqx8hHRZI= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98713: KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT Date: Sun, 18 Oct 2026 17:44:48 +0200 Message-ID: <2026101807-CVE-2026-98713-fa9a@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=2862; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=DG7ESUeRobliyMhNUaokyu0KFTtDhEmPH4wfVSflZFk=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlXXrozPX7l6PAx0udVusOyDMEMm3IBnnP5Ylvkb5/lS 5Cdd4K7I5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACZiJcQwT/FY4pePUdsPfexI TTtwsPCZ+r1baxnm6VgpznvFVPVu6aGkV28Cci9enn9FEwA= 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: arm64: Apply the fine-grained UNDEFs without FEAT_FGT FGUs don't actually require hardware support, so don't gate fgt trap config insertion on FGT. This is the only action required to allow FGUs always, as kvm_calculate_traps() already computes the FGU bits with or without FEAT_FGT. This also fixes a spurious WARN when a TLBI OS is run on a guest in vEL1 without FEAT_TLBIOS on non FEAT_FGT hardware. In this configuration the course-grained HCR_EL2.TTLBOS trap reaches the handler handle_tlbi_el1(), which expects an EL1 TLBI only from vEL2. With FGUs enabled the UNDEF will be injected without needing the specific handler. [oliver: Take Wei-Lin's suggested changelog] The Linux kernel CVE team has assigned CVE-2026-98713 to this issue. Affected and fixed versions =========================== Issue introduced in 6.9 with commit f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f and fixed in 6.12.113 with commit 2f4a15c52a552c5244ec27f4ca8bda855594f918 Issue introduced in 6.9 with commit f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f and fixed in 6.18.56 with commit 1113374a17d7f7d16b02ee0bbd9b1e7a60cbb087 Issue introduced in 6.9 with commit f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f and fixed in 7.2.10 with commit af3300b3a6bace925a496f3520e171c07b999c72 Issue introduced in 6.9 with commit f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f and fixed in 7.3-rc6 with commit 4bdd2b3a708c1feb701cb8b62feb8ad2fd77bb07 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-2026-98713 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/arm64/kvm/emulate-nested.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/2f4a15c52a552c5244ec27f4ca8bda855594f918 https://git.kernel.org/stable/c/1113374a17d7f7d16b02ee0bbd9b1e7a60cbb087 https://git.kernel.org/stable/c/af3300b3a6bace925a496f3520e171c07b999c72 https://git.kernel.org/stable/c/4bdd2b3a708c1feb701cb8b62feb8ad2fd77bb07