From patchwork Thu Feb 2 04:42:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 13125287 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 2EDF7C61DA4 for ; Thu, 2 Feb 2023 04:46:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231546AbjBBEqL (ORCPT ); Wed, 1 Feb 2023 23:46:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231899AbjBBEpe (ORCPT ); Wed, 1 Feb 2023 23:45:34 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E74397E065; Wed, 1 Feb 2023 20:44:14 -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 sin.source.kernel.org (Postfix) with ESMTPS id E5EE8CE277A; Thu, 2 Feb 2023 04:43:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36506C433A0; Thu, 2 Feb 2023 04:43:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675313032; bh=5pmjNgpnYqex7VQnVsTlAui4MzRzKxLrogzRqHiHtqg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dlSzTgDWcfQVHbIxOWU30QRZsa6UC0nR/HAKxTPBKGRCVPB4BHoMb8ekSFZRMO+B7 ENitPO148BAtIpRxK+4Kmdto3uBT/qRDhAMUDvpoAKVdbbFvB1Z3//J1IsMpkMNG2E odrpaPNBuKqqPGzUHMtCrB0a4I1e5BAXQ39pWQr8C62al00wVOzL6n4LfK04hCCGwg AsnchuGGHE23Yo1Tg5S8Y1UR+b4q0Jd7wbvzNEkTEQD06hWfOvmbSooxMeJjBdzNaO ymc+yPjxaof3UmWMVtByyLmB2TpbN8L+LML2HFf3BATg/Xjis3bKHajPxRSmhns6i0 FmbPmZRgIfoig== 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 5.4 11/17] exit: Expose "oops_count" to sysfs Date: Wed, 1 Feb 2023 20:42:49 -0800 Message-Id: <20230202044255.128815-12-ebiggers@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230202044255.128815-1-ebiggers@kernel.org> References: <20230202044255.128815-1-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 4236970aa4384..48ac68ebab728 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -63,6 +63,7 @@ #include #include #include +#include #include #include @@ -96,6 +97,25 @@ 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--; @@ -893,8 +913,6 @@ 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.