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 4B1DB585992 for ; Fri, 11 Sep 2026 19:58:19 +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=1789156704; cv=none; b=sGCZqGqSTDTIsJy+k4l/q6qp7lkk0Qgra2fakYPzkeskXKx84IkHo3xTpR41V1Xkz75TOb276trA38DpQcjq7G0EErKZYp6fUDiCoS6nFz/v47UZOQm7ItWEo8Euc3VzVe7xkyx/GoGLQf7htPfKo7FfRk5r9eTEkwbz7ZrcM6s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156704; c=relaxed/simple; bh=arrzLfELE/hMo4FUSdfp0zSNNpx9RjVKW2m8CIjafMs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ULARx5ANVfQV2l/Egdq+zhdWHLEq137EZzWeGJO75Vb8DLFpjSMiX2TpJnsJbM706+wc+k0ewu4q8Mai3O7KxdrShZtGccegeiuWRS7of8oxXqJ39pxFtJ0dVTYwSlZ6+HOXE4fRbGJfoh7Hg9X5oG81XZMLTDnO2+h8b7a06v8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=pch0zBKV; 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="pch0zBKV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3F9571F0089D; Fri, 11 Sep 2026 19:58:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156696; bh=hM7DO2txospV1LNHC7TsPVN3oBC0Np5xYvXSBbyuF8o=; h=From:To:Cc:Subject:Date:Reply-To; b=pch0zBKVbO1utbigZDp6/OW0JGmCqMNQR8Wn0oXMnxtSjiFB9AlDBwkhioef90Yss laCZ+xzRNT46CMg80XR11/noH6pAD4VPqI2vG4+tmSOLWv1vSoso7uNQs/Mg2VK/ou HdKclXz4CK3KqCK/R9X2mv7u5OyZF8lfZ0SYCr9U= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89604: efivarfs: Rate limit statfs() handler Date: Fri, 11 Sep 2026 21:44:53 +0200 Message-ID: <2026091133-CVE-2026-89604-0401@gregkh> X-Mailer: git-send-email 2.55.0 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=2757; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=aslxFC4hrJgrrjgX4mLzPHATjHRBUfhkEFZ6gEm60h4=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLInOXawWHbpNld55X+Dbm9WZ7nzU/V+WUV+peEQ29k Cq6osyrI5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACaSqccwz2TG8Z2Nk2RmX/9Y 9+tcgl7Dzw/8oQwL1i59v7z/qL3pzfyujMuXF8kyr7RWAQA= 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: efivarfs: Rate limit statfs() handler Ravi reports that statfs() may be called by unprivileged users on the efivarfs mount point, which may result in a flood of calls to the QueryVariableInfo() runtime service. These calls are disproportionately costly on x86 systems where the variable store is backed by SMM, as each SMM entry requires a rendez-vous of all the CPUs. So rate limit the calls to QueryVariableInfo() at twice per second, and return the most recently obtained value for calls that are elided. The Linux kernel CVE team has assigned CVE-2026-89604 to this issue. Affected and fixed versions =========================== Issue introduced in 6.5 with commit d86ff3333cb1d5f42d8898fb5fdb304e143c0237 and fixed in 6.12.109 with commit 8953bdd1b9c0e748d5408d3d0b8e7aeee5c9cd41 Issue introduced in 6.5 with commit d86ff3333cb1d5f42d8898fb5fdb304e143c0237 and fixed in 6.18.50 with commit 92895a14329cc9533e2a74a265214f690ba3851a Issue introduced in 6.5 with commit d86ff3333cb1d5f42d8898fb5fdb304e143c0237 and fixed in 7.2.4 with commit 0dbc2e94b81df5a1264068b6ed3605c654b8afcb Issue introduced in 6.5 with commit d86ff3333cb1d5f42d8898fb5fdb304e143c0237 and fixed in 7.3-rc1 with commit b2326338dc683e8c1067c0cbf7a47986c4190902 Issue introduced in 6.1.178 with commit 115409cbb6a296d73702a62c54c5b1b11cb88b3d 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-2026-89604 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/efivarfs/super.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/8953bdd1b9c0e748d5408d3d0b8e7aeee5c9cd41 https://git.kernel.org/stable/c/92895a14329cc9533e2a74a265214f690ba3851a https://git.kernel.org/stable/c/0dbc2e94b81df5a1264068b6ed3605c654b8afcb https://git.kernel.org/stable/c/b2326338dc683e8c1067c0cbf7a47986c4190902