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 X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B23DAC11D3D for ; Thu, 27 Feb 2020 19:35:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 750202468E for ; Thu, 27 Feb 2020 19:35:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="g/0EvsSA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730023AbgB0TfX (ORCPT ); Thu, 27 Feb 2020 14:35:23 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:40334 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727268AbgB0TfX (ORCPT ); Thu, 27 Feb 2020 14:35:23 -0500 Received: by mail-pl1-f194.google.com with SMTP id y1so202215plp.7 for ; Thu, 27 Feb 2020 11:35:22 -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:in-reply-to:references :mime-version:content-transfer-encoding; bh=46Z0N6nNFPIgM2OuwNgkHRjYe659IsqNoWw8FG0hdrY=; b=g/0EvsSAMFLQMs3F4fsuSd2nVZEd0UnWu4D3Sl3dqAK2cD5B2JP/5fjn+Xf0mTTCA1 5qBJKz6rexuU4wD/Fm2T6RKX1mqL5z11ejipV8pBRRNCR/z0fgr1nevk9cbdozCY3z4J CEEvmhdGXWUBzU64x5LbmMXX3iFxMU4Y/Igq8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=46Z0N6nNFPIgM2OuwNgkHRjYe659IsqNoWw8FG0hdrY=; b=br3DEoZLqaefuKh2WouQ/LEs6Fwy7LpqcaQjH2pPRfjO7lj1Dey4p4TxMQrWJTRGmY wEkeatiImw9ctS3vo84xV2MglPUAfdaWBIviERBDRFlAyaIhzjqZULwywFJsYjhFzf4x 7wxCwmYeJS3lA3v4z8TGynChsJPR2Gg+Ld+iQ3VZrQVo1IrIgw+DNipoqJTCoTPJG2n8 4ekTP721WEsJZBNbtoHeF8glPERloIARBT+WNJq6nVJaf56gdQTRY9c6CV+HSBgif8wa OEPPXimhXmKgfD7+j3i3UWkgj3PxfcHqWJTUcH8sBBZTHo7vPYO0ykYv+q+Ht0oHtydk J9VA== X-Gm-Message-State: APjAAAX0203ItIYRUkgXCV+JnUA2JNEvZrgoPcupF2yXUwIknZ+jcXna ayjjVT0uiaw99MrUJXQTiCcU+A== X-Google-Smtp-Source: APXvYqyO3xXE1iYRbSHC6/Q9hVVz43xR0biiVO0z4es+cZucLAEsJlQuw4NFe3BlB1tUhIBv2xxm2g== X-Received: by 2002:a17:90a:c24c:: with SMTP id d12mr520844pjx.113.1582832121953; Thu, 27 Feb 2020 11:35:21 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id p18sm11620140pjo.3.2020.02.27.11.35.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Feb 2020 11:35:20 -0800 (PST) From: Kees Cook To: Andrew Morton Cc: Kees Cook , Andrey Ryabinin , Elena Petrova , Andrey Konovalov , Alexander Potapenko , Dan Carpenter , "Gustavo A. R. Silva" , Arnd Bergmann , Ard Biesheuvel , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com, syzkaller@googlegroups.com Subject: [PATCH v5 4/6] ubsan: Check panic_on_warn Date: Thu, 27 Feb 2020 11:35:14 -0800 Message-Id: <20200227193516.32566-5-keescook@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200227193516.32566-1-keescook@chromium.org> References: <20200227193516.32566-1-keescook@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Syzkaller expects kernel warnings to panic when the panic_on_warn sysctl is set. More work is needed here to have UBSan reuse the WARN infrastructure, but for now, just check the flag manually. Link: https://lore.kernel.org/lkml/CACT4Y+bsLJ-wFx_TaXqax3JByUOWB3uk787LsyMVcfW6JzzGvg@mail.gmail.com Signed-off-by: Kees Cook --- lib/ubsan.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/lib/ubsan.c b/lib/ubsan.c index 7b9b58aee72c..429663eef6a7 100644 --- a/lib/ubsan.c +++ b/lib/ubsan.c @@ -156,6 +156,17 @@ static void ubsan_epilogue(void) "========================================\n"); current->in_ubsan--; + + if (panic_on_warn) { + /* + * This thread may hit another WARN() in the panic path. + * Resetting this prevents additional WARN() from panicking the + * system on this thread. Other threads are blocked by the + * panic_mutex in panic(). + */ + panic_on_warn = 0; + panic("panic_on_warn set ...\n"); + } } static void handle_overflow(struct overflow_data *data, void *lhs, -- 2.20.1