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 55E75C33CB3 for ; Thu, 16 Jan 2020 01:24:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2EB322467E for ; Thu, 16 Jan 2020 01:24:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="YBfsq7Ez" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730101AbgAPBYh (ORCPT ); Wed, 15 Jan 2020 20:24:37 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:41298 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729742AbgAPBYZ (ORCPT ); Wed, 15 Jan 2020 20:24:25 -0500 Received: by mail-pg1-f196.google.com with SMTP id x8so9040707pgk.8 for ; Wed, 15 Jan 2020 17:24:25 -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=8H0Ju2Tzkc7Hi4GTApYP4I+j3crkZ0C4oDWnN2FFbsw=; b=YBfsq7Ezv9QYWZccbUoWAnosaxltJReREbQgD47d8e4wJ+Ejg4Gn/vs3HhD5eYzXQr oJSYxgIJL4FY50iMU0/0GHsjGfjdVuL9/LFpgrcASS5CbKRGtx4pLqrpDWIs3X6BUzT1 x8tB+7PXLZLkr6MHrizsmnC10IzFOgJdvcjV8= 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=8H0Ju2Tzkc7Hi4GTApYP4I+j3crkZ0C4oDWnN2FFbsw=; b=Xexqw4PoXsMyfeL3Z4RvVw2h4KrSFFstwBPIdde+L6s1uJZfJpSEqi6KELG8gZMqe+ /9pGSp09JVjJrv+N/NRpljAIcRuD9RZUxy3WraRMyqLb2KIVXHrvAmPw7kcN3XK2VpR3 ePv0IlDsxQbw2KmNXjAegqRtfa/Tr7YPMXXMDktShxds9Qf/B2z+gCA7RU8Qd9i4JDor oCeaotH3NsvqpKkjYxFyT8odQ+6zGg8UxxU1WC/vVv68LNmykUB+QvdMvmq/lc6V3mto uKdA1cBVrnR7hQZuHuO4Sm4cDI1RHitrO1p6z9MS6JNzc4AkJ+77lWA5YihXjrGvgqMO h9jg== X-Gm-Message-State: APjAAAXJm9CSEofY3uCnoY3c/efTIyXTI+BdpoN7RbFdLe3lmvXWYkr3 +UNp9iJOo1Eg9yvTl6CpStXTzw== X-Google-Smtp-Source: APXvYqyCry89U8JhHB2JmnnGGqfqp6e2/sFNsw+rUzw40rZSQ9y3ohq76mRbxz8eJb3EdmcaMK/hOw== X-Received: by 2002:aa7:98d0:: with SMTP id e16mr33457061pfm.77.1579137865146; Wed, 15 Jan 2020 17:24:25 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id d1sm1046181pjx.6.2020.01.15.17.24.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jan 2020 17:24:23 -0800 (PST) From: Kees Cook To: Andrew Morton Cc: Kees Cook , Andrey Ryabinin , Elena Petrova , 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 v3 5/6] kasan: Unset panic_on_warn before calling panic() Date: Wed, 15 Jan 2020 17:23:20 -0800 Message-Id: <20200116012321.26254-6-keescook@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116012321.26254-1-keescook@chromium.org> References: <20200116012321.26254-1-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 As done in the full WARN() handler, panic_on_warn needs to be cleared before calling panic() to avoid recursive panics. Signed-off-by: Kees Cook --- mm/kasan/report.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 621782100eaa..844554e78893 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -92,8 +92,16 @@ static void end_report(unsigned long *flags) pr_err("==================================================================\n"); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); spin_unlock_irqrestore(&report_lock, *flags); - if (panic_on_warn) + 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"); + } kasan_enable_current(); } -- 2.20.1