From patchwork Thu Feb 2 05:26:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 51700 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:eb09:0:0:0:0:0 with SMTP id s9csp52659wrn; Wed, 1 Feb 2023 21:30:09 -0800 (PST) X-Google-Smtp-Source: AK7set+dMtvGG5H2EeU4DjspCI/Z49DVwNsR346L5diIM0CBhCtwbcWevEgsGjt0NUqwSDhRomeH X-Received: by 2002:a17:902:d506:b0:198:9e29:cc4f with SMTP id b6-20020a170902d50600b001989e29cc4fmr6777548plg.43.1675315808719; Wed, 01 Feb 2023 21:30:08 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1675315808; cv=none; d=google.com; s=arc-20160816; b=f97TVHwDwWFkHukuBrHmYZ25G3AV3EJsAZsxCg312ZhPx+nd+QsQNmpKHPaTPSNh9L I4C7SGVIUW22XGB47DChA9kWimPQAlq6/0frRIJomaVJXty5DPEHENDK+zOQra3Wpul6 Hr/KTpX5lHU2EcNOoDn24wrUY+EJLfwRZlwyltmUtAeR1ocnlm9u07yo5bS2nVWb/ymm Zz+uJ/HCkzSdtUTjKXO5oHTIY+QHywc0wRIPjTulKyRBhsvSR6Hvqab9ATnildpm7lyn 39erYRS2zDrZls0492UGQauLepQqGB/VctJR5cLizOlezK3KBmGIuCQfMCsh10UgEfIr Ikvg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=wcesQKKxvYorIbnTbKNXep7QqgjOlqPk5sNXgtyqH9I=; b=g9ynIG8pz13+EWNXSRhn1cE/xNFLQRVDGGTT8PNDJ0gbZoO7apoRVgW90fU8wNGVfN I+bwNp99YYtYQEWWohyCb7t+3u7x2d79WcQEr48YqvMERE+WMoPKMTT5aGtJnjrWgSOy wvvfG9F3fLrQDvfKYEHKrsHSyABf3p0ZrHsxqPqg7WvR0jJqzlxS6Y4FHZOPr6gVFqIX nGIOtnZxoRBVPOTBtSTpB0tMuQDp4ql4q1ft8S3kniFSfhGtKQVqCnMkmXHZOa5m3BGU R8EGanLraqjV6FFuKhYF94wTdZw63wXl1G1ZvuZntdw3lo01DZQye00CL/Grb+Pnuc6N 1iKg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=LlplLbAJ; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id s1-20020a170902988100b00194967b7badsi16961549plp.591.2023.02.01.21.29.56; Wed, 01 Feb 2023 21:30:08 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=LlplLbAJ; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230147AbjBBF3K (ORCPT + 99 others); Thu, 2 Feb 2023 00:29:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231691AbjBBF2Y (ORCPT ); Thu, 2 Feb 2023 00:28:24 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8310C1F5D6; Wed, 1 Feb 2023 21:28:10 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CBFD8615EB; Thu, 2 Feb 2023 05:28:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C096C4339E; Thu, 2 Feb 2023 05:28:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675315689; bh=wDzo53Dl0UDwP01U6Ffmf8hrLpT0FCIt+byjVDuB7aY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LlplLbAJlnEemvNaUO2Mz2C0sOMCIG1zXP6tRmNnDsU+D6CxCwFp5IeajaTiCs/2F DmfoAsF5RcQSOP7rw7NMOJrgBnQNHU3UzDgM+uRY3XEAXV4QB57erhrTAemyHhCZsl YSBSgS4+zaiXIIhidKtDXgwOolhfXQjwrZYRBqLbGzBZlRu+yAX0OhSUV6S+3YtL4N nTntuRWBnqbgcPH2od+JnCFH1K1lXb22QX+3LxU4sbAM00ConG16KSuR1iuqN/mnq8 zvxv6jeHbT78QgFezP52ak05ae8BA1O+Ozzr1EEJDyTL7ZqnQGWPi64/yd0hlmQCsz DAr1sLanvmqWw== From: Eric Biggers To: stable@vger.kernel.org Cc: Harshit Mogalapalli , Kees Cook , SeongJae Park , Seth Jenkins , Jann Horn , "Eric W . Biederman" , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Jonathan Corbet , Andrew Morton , Baolin Wang , "Jason A. Donenfeld" , Eric Biggers , Huang Ying , Petr Mladek , tangmeng , "Guilherme G. Piccoli" , Tiezhu Yang , Sebastian Andrzej Siewior , linux-doc@vger.kernel.org, Luis Chamberlain Subject: [PATCH 4.19 13/16] panic: Introduce warn_limit Date: Wed, 1 Feb 2023 21:26:01 -0800 Message-Id: <20230202052604.179184-14-ebiggers@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230202052604.179184-1-ebiggers@kernel.org> References: <20230202052604.179184-1-ebiggers@kernel.org> MIME-Version: 1.0 X-Spam-Status: No, score=-7.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1756695949093524501?= X-GMAIL-MSGID: =?utf-8?q?1756695949093524501?= From: Kees Cook commit 9fc9e278a5c0b708eeffaf47d6eb0c82aa74ed78 upstream. Like oops_limit, add warn_limit for limiting the number of warnings when panic_on_warn is not set. Cc: Jonathan Corbet Cc: Andrew Morton Cc: Baolin Wang Cc: "Jason A. Donenfeld" Cc: Eric Biggers Cc: Huang Ying Cc: Petr Mladek Cc: tangmeng Cc: "Guilherme G. Piccoli" Cc: Tiezhu Yang Cc: Sebastian Andrzej Siewior Cc: linux-doc@vger.kernel.org Reviewed-by: Luis Chamberlain Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20221117234328.594699-5-keescook@chromium.org Signed-off-by: Eric Biggers --- Documentation/sysctl/kernel.txt | 10 ++++++++++ kernel/panic.c | 27 +++++++++++++++++++++++++++ 2 files changed, 37 insertions(+) diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index e1d375df4f286..c8d3dbda3c1e2 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -97,6 +97,7 @@ show up in /proc/sys/kernel: - threads-max - unprivileged_bpf_disabled - unknown_nmi_panic +- warn_limit - watchdog - watchdog_thresh - version @@ -1114,6 +1115,15 @@ example. If a system hangs up, try pressing the NMI switch. ============================================================== +warn_limit: + +Number of kernel warnings after which the kernel should panic when +``panic_on_warn`` is not set. Setting this to 0 disables checking +the warning count. Setting this to 1 has the same effect as setting +``panic_on_warn=1``. The default value is 0. + +============================================================== + watchdog: This parameter can be used to disable or enable the soft lockup detector diff --git a/kernel/panic.c b/kernel/panic.c index 08b8adc55b2bf..d1a5360262f04 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -42,6 +42,7 @@ static int pause_on_oops_flag; static DEFINE_SPINLOCK(pause_on_oops_lock); bool crash_kexec_post_notifiers; int panic_on_warn __read_mostly; +static unsigned int warn_limit __read_mostly; int panic_timeout = CONFIG_PANIC_TIMEOUT; EXPORT_SYMBOL_GPL(panic_timeout); @@ -50,6 +51,26 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list); EXPORT_SYMBOL(panic_notifier_list); +#ifdef CONFIG_SYSCTL +static struct ctl_table kern_panic_table[] = { + { + .procname = "warn_limit", + .data = &warn_limit, + .maxlen = sizeof(warn_limit), + .mode = 0644, + .proc_handler = proc_douintvec, + }, + { } +}; + +static __init int kernel_panic_sysctls_init(void) +{ + register_sysctl_init("kernel", kern_panic_table); + return 0; +} +late_initcall(kernel_panic_sysctls_init); +#endif + static long no_blink(int state) { return 0; @@ -127,8 +148,14 @@ EXPORT_SYMBOL(nmi_panic); void check_panic_on_warn(const char *origin) { + static atomic_t warn_count = ATOMIC_INIT(0); + if (panic_on_warn) panic("%s: panic_on_warn set ...\n", origin); + + if (atomic_inc_return(&warn_count) >= READ_ONCE(warn_limit) && warn_limit) + panic("%s: system warned too often (kernel.warn_limit is %d)", + origin, warn_limit); } /**