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 D7B2DC4332F for ; Wed, 21 Dec 2022 12:50:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231617AbiLUMuT (ORCPT ); Wed, 21 Dec 2022 07:50:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229601AbiLUMuR (ORCPT ); Wed, 21 Dec 2022 07:50:17 -0500 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EAF222BF5 for ; Wed, 21 Dec 2022 04:50:16 -0800 (PST) Received: by mail-ej1-x633.google.com with SMTP id bj12so36459209ejb.13 for ; Wed, 21 Dec 2022 04:50:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=cc:to:message-id:date:from:content-transfer-encoding:mime-version :subject:from:to:cc:subject:date:message-id:reply-to; bh=WMiE0vd/yYBaXGsz07hU3FBQiAft2wmjzq4IoD9fajA=; b=FsDwchrubRoccRz16UU3/VfvJCLPLXjk9mbF3gAuquaoYgXTYXOxrdFCpS6vCpy75E 98jX7Jg91/wbuAw2LVOYnSMwt9XdTJpru7YFRAagTsctrMCnq4nkKHOoviboa8xmKyYy qXFv71vL8uYh9dE5jZxt6PCYEu4NaMd2SXkmQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:message-id:date:from:content-transfer-encoding:mime-version :subject:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=WMiE0vd/yYBaXGsz07hU3FBQiAft2wmjzq4IoD9fajA=; b=4I+HBiePGcFkFeL/AHtYFHnoLVT72NiTyUirhtqeVEyPeU3i8AwaDf37c6tFt+sZr+ xc/V5aiO6BfAyOISAdI7aBAmzcFngECk7cdqC3l8LeP+eylivN2YZFMN0eSO1Kre3v6Q jT9xs0wWYjsiPkHnyQx8kv9IxbphF7kN7GN88lNdwlk4HLkEyToyJdnTqZhblji2gspX moik/zeDVsOU3QJ3GDj+86M7NjqDCkEoksg1WG4pnEhOwhAoCIkf3gxfWfPJNF06cGAo aTKnu+hU8jMhIOWwaURu9Sh7XL8GYn/JlHKeid1CD73Dw/grGhTYlkLKXGhNf4WukjS3 qPeQ== X-Gm-Message-State: AFqh2krcgKh62Z1uJya2ip3GyI6/9rLR39safyQM5svgOytJJjqwmeyr LRF12YdxnytPSBIphTlmbXnxeA== X-Google-Smtp-Source: AMrXdXuil/5SfXayT9oVY55/8d68hsnH602ZQHAwgj636BYZ+mDSkdlwA3kBxhfcmcYQOjM14us5Lg== X-Received: by 2002:a17:906:6543:b0:81a:bebd:d4b0 with SMTP id u3-20020a170906654300b0081abebdd4b0mr1316054ejn.44.1671627015175; Wed, 21 Dec 2022 04:50:15 -0800 (PST) Received: from alco.roam.corp.google.com ([2620:0:1059:10:4b82:b1f8:cb4f:fbbd]) by smtp.gmail.com with ESMTPSA id w7-20020a170906b18700b007c0b28b85c5sm7039250ejy.138.2022.12.21.04.50.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Dec 2022 04:50:14 -0800 (PST) Subject: [PATCH v4 0/3] kexec: Add new parameter to limit the access to kexec MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-B4-Tracking: v=1; b=H4sIAPgAo2MC/43NTQrCMBAF4KtI1kY6SWobV95DXCTppAn2B5K2KK V3d3ApIl0N78H7ZmUZU8TMLoeVJVxijuNAQR0PzAUztMhjQ5mJQggAULyJ2dgO+QOf6HjCjBMHbS sEqKSsPaOlNRm5TWZwgbbD3HVUhpinMb0+nxagc/uPLsAL7m0JjSicryu4upDGPs79aUwtuxO5iB 2MIMYpXUuQDqwtfzByByOJUegVaqFN489fzLZtb9GhTkdMAQAA From: Ricardo Ribalda Date: Wed, 21 Dec 2022 13:50:00 +0100 Message-Id: <20221114-disable-kexec-reset-v4-0-ab809c8d988c@chromium.org> To: Jonathan Corbet , Philipp Rudo , Eric Biederman , "Guilherme G. Piccoli" Cc: kexec@lists.infradead.org, Ricardo Ribalda , Ross Zwisler , Steven Rostedt , "Joel Fernandes (Google)" , Sergey Senozhatsky , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org X-Mailer: b4 0.11.0-dev-696ae X-Developer-Signature: v=1; a=openpgp-sha256; l=2161; i=ribalda@chromium.org; h=from:subject:message-id; bh=VBCVJ+aD/h3GyICYpp+9hUZz7wDvOWS2v3+hHEeVJG0=; b=owEBbQKS/ZANAwAKAdE30T7POsSIAcsmYgBjowD7/oKW4m0F/oh1hjb/+F27kY8sEEjovm4nldnc ++mdDAKJAjMEAAEKAB0WIQREDzjr+/4oCDLSsx7RN9E+zzrEiAUCY6MA+wAKCRDRN9E+zzrEiCRiD/ 4v6YHmqUA36mCtnhhZgNBiEwdUEvmgxZ0WLQ4heB78T72NPYXMF09anLaJ0p7l9FdGBGNT8FA6eQX6 GQ15UnOLfNCaGiI/XMktb6T29UUA0gIGq7ohW6vzrUJnHk90jo8cCv5cQGQFZFyHPQGZWE9CYBzkgB WsJEXQnvLfqGLfXW8XiBP2eWlUINVEyMsD60u/ZejcyICdnllmnY3gjCCg5wIRQQXDh4H1dT6MSMev 4XFxYK25FDX3N5xFTmdynwhI2rhSfxrZuzUjOQg9g4sL6Bhi4jsZOwOLJKADo/maI/Fk7cjfbyKCOu r7ZsRslYNoVOvTkdqlaXW+OPbGDHWwboSFtoY2B0yKURuz1q476QsDy+2oqi4dwhlJLkKjNpjCK9Ur oRmVio+DnU1g5F3x8dcOMO4ig6LNM+i39llbr82wzYrmpbyH/8o84fmXXWVdcxTGSI3g3muSijaL5X 3I1Gr7LRTn8ed42PY5sJy3FQp5EO0BpB7+zB3trHkYwieE3tgLvXEWR1oSl6NDVycl9AabG3Hdm1+I cYBCqGkabyDdzpOMzrARBMdldMekG2cOzqeznE1ru8e+Rz4N6VADI1cVvzpZ5Ku490beZmS64FgK+g wrPGrb0s45Ggx/t6+rvZdjIBLsohAJeqd4XK4fJdOXy/EUvBtgRxRf1V12Gw== X-Developer-Key: i=ribalda@chromium.org; a=openpgp; fpr=9EC3BB66E2FC129A6F90B39556A0D81F9F782DA9 Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Add two parameter to specify how many times a kexec kernel can be loaded. These parameter allow hardening the system. While we are at it, fix a documentation issue and refactor some code. To: Jonathan Corbet To: Eric Biederman Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: kexec@lists.infradead.org Cc: Joel Fernandes (Google) Cc: Sergey Senozhatsky Cc: Steven Rostedt Cc: Ross Zwisler To: Philipp Rudo To: Guilherme G. Piccoli Signed-off-by: Ricardo Ribalda --- Changes in v4 (Thanks Steven!): - Uses sysctl instead or module_parameters - Pass image type instead of boolean to permitted - Fix typo on flag handling - Return -EINVAL for values that does not change the current value. - Link to v3: https://lore.kernel.org/r/20221114-disable-kexec-reset-v3-0-4ef4e929adf6@chromium.org Changes in v3: - s/paramter/parameter/ Thanks Ghilherme! - s/permited/permitted/ Thanks Joel! - Link to v2: https://lore.kernel.org/r/20221114-disable-kexec-reset-v2-0-c498313c1bb5@chromium.org Changes in v2: - Instead of kexec_reboot_disabled, add two new counters (Thanks Philipp!) - Link to v1: https://lore.kernel.org/r/20221114-disable-kexec-reset-v1-0-fb51d20cf871@chromium.org --- Ricardo Ribalda (3): Documentation: sysctl: Correct kexec_load_disabled kexec: Factor out kexec_load_permitted kexec: Introduce sysctl parameters kexec_load_limit_* Documentation/admin-guide/sysctl/kernel.rst | 25 +++++++- include/linux/kexec.h | 3 +- kernel/kexec.c | 4 +- kernel/kexec_core.c | 96 ++++++++++++++++++++++++++++- kernel/kexec_file.c | 11 ++-- 5 files changed, 129 insertions(+), 10 deletions(-) --- base-commit: 479174d402bcf60789106eedc4def3957c060bad change-id: 20221114-disable-kexec-reset-19b7e117338f Best regards, -- Ricardo Ribalda