From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2FF6BC4321E for ; Thu, 10 Feb 2022 02:53:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231645AbiBJCxY (ORCPT ); Wed, 9 Feb 2022 21:53:24 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:56604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229783AbiBJCxW (ORCPT ); Wed, 9 Feb 2022 21:53:22 -0500 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0DE092409C for ; Wed, 9 Feb 2022 18:53:24 -0800 (PST) Received: by mail-pj1-x1030.google.com with SMTP id on2so3915775pjb.4 for ; Wed, 09 Feb 2022 18:53:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=H8yuowP1mvnDP9KBlBJhs+EnqVN/L7/OeGc4T0MUUiI=; b=g3Y3erdYSib9j/KQ5dVDkf9MH5o6tk7fSy3xi0e7V484U3gvKLCnVzajg8vgMbwvX1 Jjnrv+KBTSKJQDdGJbzVPu7uadccKPxqe4E2p99bdkQOVJTvNA5AhIBxn1wFhRuK/weP 9IYh32uj8DKIO1dyV7kxJg9k3xnMFL3G7baZM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=H8yuowP1mvnDP9KBlBJhs+EnqVN/L7/OeGc4T0MUUiI=; b=VaGNI+Y1CJh4LcTzPCuKVz8w2e+bRqKVNkcz0au3o++9q/Ulv/P+ll7sFM+sNhK17i f1o3qoeCmgJAwNtYKoqOZdRp2mg7uMZv+yerF+L+h9m0WEZutHnNy9KOW0iNo4Z7XP40 W4ylMTaPts96AtRjAF+VKF4S4+6HZkH5G6N9zY675VK3lQ7nEGJ455zeYQS29G0dBW9r SLgPO2ajdFRuSR9DJW4906bI+NyVmPjdJVQ1bRqRB57/CezoWCeDAEc8zlz41oRxAWo0 9bBN/tD2RwOS18ItaiBfxn0LJTiGXAM3UlouvtN5XyFEpQMWFiohJX8OfJu4dxb3ReMY t5AQ== X-Gm-Message-State: AOAM533W3U41l3cm6Z7yvYpUfAe8x+0ZepLg29XiZ4IuiGm/nnurqoOQ /AVUR+3SgQxbAP4HUZk+vHnrbg== X-Google-Smtp-Source: ABdhPJyL8cIqzqClp86dbDBLCDXuzRTYQHVGbS1hWszwpQyFYwKZ3Z+2yLCflwC+36gHOAlNqTd1JQ== X-Received: by 2002:a17:902:c24d:: with SMTP id 13mr5363988plg.22.1644461603571; Wed, 09 Feb 2022 18:53:23 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id i10sm676425pjd.2.2022.02.09.18.53.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Feb 2022 18:53:23 -0800 (PST) From: Kees Cook To: "Eric W. Biederman" Cc: Kees Cook , =?UTF-8?q?Robert=20=C5=9Awi=C4=99cki?= , Andy Lutomirski , Will Drewry , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH 0/3] signal: HANDLER_EXIT should clear SIGNAL_UNKILLABLE Date: Wed, 9 Feb 2022 18:53:18 -0800 Message-Id: <20220210025321.787113-1-keescook@chromium.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Developer-Signature: v=1; a=openpgp-sha256; l=907; h=from:subject; bh=hTr0tOO4h3lt/wmDEd+6435u89taCT0sXulysY0LXCw=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBiBH4gQ43Wy8/NXcOkUg/7VSRgkMgvhZk6QoYYYdXd mO5Dn9eJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCYgR+IAAKCRCJcvTf3G3AJtu6D/ 9Qs9NPuLfVzVfEw8ZNSLED2BCppQF666ohGTYmyF6E1tkcRI4mFt87GMbc7/B+wLkWc2UcnK+lhCcC XoYNMKZ0e4yh+6EcfHj3UPpOVsMJVImlbfnQe2lzlENx0eUD3Psh/i2MNykflD/nDXYGMeR3i0URVS QtvJz2vXvRFAZNf3PluThlzT1YU6gy+SXSf1UF9y3hFrmLDAVpdfM9mAVlS4Ur1zgIlYKZsUOAqNUg 3NUGZ6cMj1Zaap9Hd+PgMDZW/2b2jbAgwbIFvG1cjqrtH1K0wamutZVA9rHieLCId8m3A9+78e+K4I L7m5SuS48W1jq6TxHhb8YXgPaQDl9uN+67ff8F4hnWXz+zoa0LvkiLwWdxmGE5OG7WoZ0blf+DJx3T z04beNzndFVKYD+rI73h7xQ0UjzsXUeRiyNm73yeSxufBCGEeyHT+zQ3GffJD2IlqIL5oonq6pkP8c q4fW2+5DpUAfkHr7xrCeZKqn2sUJZ9MReYGyoeVHjiyTZx2IMBFER4FDA/tUU9jE6d6QvtbeWM6NzM eGMpWqlVnFnfVkTG27QUfboS+FmB7PYW/4M3Rs7gXL1iwn9xkqbz6F4eDrZI3fBFaQnkzW/MTwmBhk tIS4f3zFRoSi1f+lE7DjclN2KQB3mEOiDP09xXX2C0RJU/ggN8Dov4F7cOOQ== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, This fixes the signal refactoring to actually kill unkillable processes when receiving a fatal SIGSYS from seccomp. Thanks to Robert for the report and Eric for the fix! I've also tweaked seccomp internal a bit to fail more safely. This was a partial seccomp bypass, in the sense that SECCOMP_RET_KILL_* didn't kill the process, but it didn't bypass other aspects of the filters. (i.e. the syscall was still blocked, etc.) I'll be sending this to Linus after a bit more testing... Thanks, -Kees Kees Cook (3): signal: HANDLER_EXIT should clear SIGNAL_UNKILLABLE seccomp: Invalidate seccomp mode to catch death failures samples/seccomp: Adjust sample to also provide kill option kernel/seccomp.c | 10 ++++++++++ kernel/signal.c | 5 +++-- samples/seccomp/dropper.c | 9 +++++++-- 3 files changed, 20 insertions(+), 4 deletions(-) -- 2.30.2