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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 2C709C2BABC for ; Tue, 7 Apr 2020 03:12:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E5E8120801 for ; Tue, 7 Apr 2020 03:12:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="o7mplNOJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5E8120801 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 917FC8E00A9; Mon, 6 Apr 2020 23:12:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8C8A38E0062; Mon, 6 Apr 2020 23:12:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7DF388E00A9; Mon, 6 Apr 2020 23:12:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0122.hostedemail.com [216.40.44.122]) by kanga.kvack.org (Postfix) with ESMTP id 63BB88E0062 for ; Mon, 6 Apr 2020 23:12:44 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 26045181AEF39 for ; Tue, 7 Apr 2020 03:12:44 +0000 (UTC) X-FDA: 76679586648.06.crow86_17d8e7199ad0d X-HE-Tag: crow86_17d8e7199ad0d X-Filterd-Recvd-Size: 3182 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Tue, 7 Apr 2020 03:12:43 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AF0212072F; Tue, 7 Apr 2020 03:12:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586229163; bh=ftipdtJl/ghhzAkhBE4bXFi5pZ0KU/+hOSscASO/2WU=; h=Date:From:To:Subject:In-Reply-To:From; b=o7mplNOJnh3D8/VOimLd/UJwutpc+p4zsYO1YXW5sE/LodkItRulFbQuxUzKgrERf HJOA7aR/MpLjWOa1WVeDFwpyfQV/pSWgr5BkkYPqIZ0PO2V1VwHb8UjmNRrqTS15Rl 9yJGac15/TmIEtVN1OHvYfzXsYz+0HtizTc2EpiA= Date: Mon, 06 Apr 2020 20:12:42 -0700 From: Andrew Morton To: akpm@linux-foundation.org, andreyknvl@google.com, ard.biesheuvel@linaro.org, arnd@arndb.de, aryabinin@virtuozzo.com, dan.carpenter@oracle.com, dvyukov@google.com, glider@google.com, gustavo@embeddedor.com, keescook@chromium.org, lenaptr@google.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 162/166] kasan: unset panic_on_warn before calling panic() Message-ID: <20200407031242.brxg9O47-%akpm@linux-foundation.org> In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Kees Cook Subject: kasan: unset panic_on_warn before calling panic() As done in the full WARN() handler, panic_on_warn needs to be cleared before calling panic() to avoid recursive panics. Link: http://lkml.kernel.org/r/20200227193516.32566-6-keescook@chromium.org Signed-off-by: Kees Cook Acked-by: Dmitry Vyukov Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Dan Carpenter Cc: Elena Petrova Cc: "Gustavo A. R. Silva" Signed-off-by: Andrew Morton --- mm/kasan/report.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/mm/kasan/report.c~kasan-unset-panic_on_warn-before-calling-panic +++ a/mm/kasan/report.c @@ -92,8 +92,16 @@ static void end_report(unsigned long *fl 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(); } _