From patchwork Fri Feb 3 00:33:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 13126866 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 50453C63797 for ; Fri, 3 Feb 2023 00:35:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233390AbjBCAfs (ORCPT ); Thu, 2 Feb 2023 19:35:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232937AbjBCAfd (ORCPT ); Thu, 2 Feb 2023 19:35:33 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 200FA63871; Thu, 2 Feb 2023 16:35:28 -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 D5E7761D48; Fri, 3 Feb 2023 00:35:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5962DC433EF; Fri, 3 Feb 2023 00:35:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675384526; bh=NvHqmOgG2aAfs54Rnjd2jLih4AMjzsSDG6iFMQBllZY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l6SyG6UWMh4edXuuDsz+y+xJ+BlvUaVDoEgAgY7UttYMq+mlXaBdvu9DI+ZRnGX37 B4NO/big5hpcoPizMQiuD2qe1MBjM6cJSPsG78wEl9sbp/MFcJ9rA/d2esIiD3JdeG y31vAju5c+PHVyzJZtad/r5LlmNsfOFT+neAv1yygp9VbcjhUWDKfH3teSPFUkZmJD HTizb44xKlcWUq9AL9NTb6nDZzSN4WK5uGFfOQKqjsjdvsjHw+ScsAjtTopzrArmln 4YYqvIxdFNQ96oJCYM49y32flzs2eft4gg/cM9etp7H+IolfGvGTJheWu4GKLAxxT0 3N54E99TcKqtQ== 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, Arnd Bergmann , Luis Chamberlain Subject: [PATCH 4.14 v2 09/15] exit: Expose "oops_count" to sysfs Date: Thu, 2 Feb 2023 16:33:48 -0800 Message-Id: <20230203003354.85691-10-ebiggers@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230203003354.85691-1-ebiggers@kernel.org> References: <20230203003354.85691-1-ebiggers@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Kees Cook commit 9db89b41117024f80b38b15954017fb293133364 upstream. Since Oops count is now tracked and is a fairly interesting signal, add the entry /sys/kernel/oops_count to expose it to userspace. Cc: "Eric W. Biederman" Cc: Jann Horn Cc: Arnd Bergmann Reviewed-by: Luis Chamberlain Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20221117234328.594699-3-keescook@chromium.org Signed-off-by: Eric Biggers --- .../ABI/testing/sysfs-kernel-oops_count | 6 +++++ kernel/exit.c | 22 +++++++++++++++++-- 2 files changed, 26 insertions(+), 2 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-kernel-oops_count diff --git a/Documentation/ABI/testing/sysfs-kernel-oops_count b/Documentation/ABI/testing/sysfs-kernel-oops_count new file mode 100644 index 0000000000000..156cca9dbc960 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-oops_count @@ -0,0 +1,6 @@ +What: /sys/kernel/oops_count +Date: November 2022 +KernelVersion: 6.2.0 +Contact: Linux Kernel Hardening List +Description: + Shows how many times the system has Oopsed since last boot. diff --git a/kernel/exit.c b/kernel/exit.c index 482bcaf158127..138b110bf83a1 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -62,6 +62,7 @@ #include #include #include +#include #include #include @@ -95,6 +96,25 @@ static __init int kernel_exit_sysctls_init(void) late_initcall(kernel_exit_sysctls_init); #endif +static atomic_t oops_count = ATOMIC_INIT(0); + +#ifdef CONFIG_SYSFS +static ssize_t oops_count_show(struct kobject *kobj, struct kobj_attribute *attr, + char *page) +{ + return sysfs_emit(page, "%d\n", atomic_read(&oops_count)); +} + +static struct kobj_attribute oops_count_attr = __ATTR_RO(oops_count); + +static __init int kernel_exit_sysfs_init(void) +{ + sysfs_add_file_to_group(kernel_kobj, &oops_count_attr.attr, NULL); + return 0; +} +late_initcall(kernel_exit_sysfs_init); +#endif + static void __unhash_process(struct task_struct *p, bool group_dead) { nr_threads--; @@ -949,8 +969,6 @@ EXPORT_SYMBOL_GPL(do_exit); void __noreturn make_task_dead(int signr) { - static atomic_t oops_count = ATOMIC_INIT(0); - /* * Take the task off the cpu after something catastrophic has * happened.