From patchwork Thu Feb 2 05:43:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 13125343 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 78B73C05027 for ; Thu, 2 Feb 2023 05:45:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230116AbjBBFpZ (ORCPT ); Thu, 2 Feb 2023 00:45:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229988AbjBBFpY (ORCPT ); Thu, 2 Feb 2023 00:45:24 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79A053644C; Wed, 1 Feb 2023 21:45:23 -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 153C9615F2; Thu, 2 Feb 2023 05:45:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D2E0CC433A4; Thu, 2 Feb 2023 05:45:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675316722; bh=ZrJE/T7SLlHhvTiGljJycVNk4Ss4UF98+LFJwDCgDho=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Opw6F21NCn/0eyL0JLjPetpv06wMS1xqhkHxD7snPBkviI/mJsQKP/Q+P2wQBCpG0 dn0srPB0+54tGOBE/Z1tHcNkwTLL6T4jhaKZtKpD+GBrVjNyMuflIOy9uhPsug+uUH 5EnlWsaC4jLiXXyBfCbriwDPR0nOMoJzWMghS1ryuMt+6rdsj+dz2ifZOA8UBqzhR1 YB5A2ybGDH+1Y7DPZoYtq0AFY9XjFBPU7y4VFYxpOxOzl3tOTGnmXCoRzGyw6zV8iN fcI4eosEEK80ZuEqgBwq6QZiVYJ0Lo2IuS5Ko6NLonxQypow2UbrfYw+Qg/zYCXXO2 mhnj3a9M2DG7g== 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, Andrey Ryabinin , Dmitry Vyukov , Ingo Molnar , Juri Lelli , Patricia Alfonso , Peter Zijlstra , Shuah Khan , Vincent Guittot , David Gow , Andrew Morton , Andrey Konovalov , Brendan Higgins , Linus Torvalds Subject: [PATCH 4.14 03/16] mm: kasan: do not panic if both panic_on_warn and kasan_multishot set Date: Wed, 1 Feb 2023 21:43:53 -0800 Message-Id: <20230202054406.221721-4-ebiggers@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230202054406.221721-1-ebiggers@kernel.org> References: <20230202054406.221721-1-ebiggers@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: David Gow commit be4f1ae978ffe98cc95ec49ceb95386fb4474974 upstream. KASAN errors will currently trigger a panic when panic_on_warn is set. This renders kasan_multishot useless, as further KASAN errors won't be reported if the kernel has already paniced. By making kasan_multishot disable this behaviour for KASAN errors, we can still have the benefits of panic_on_warn for non-KASAN warnings, yet be able to use kasan_multishot. This is particularly important when running KASAN tests, which need to trigger multiple KASAN errors: previously these would panic the system if panic_on_warn was set, now they can run (and will panic the system should non-KASAN warnings show up). Signed-off-by: David Gow Signed-off-by: Andrew Morton Tested-by: Andrey Konovalov Reviewed-by: Andrey Konovalov Reviewed-by: Brendan Higgins Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Ingo Molnar Cc: Juri Lelli Cc: Patricia Alfonso Cc: Peter Zijlstra Cc: Shuah Khan Cc: Vincent Guittot Link: https://lkml.kernel.org/r/20200915035828.570483-6-davidgow@google.com Link: https://lkml.kernel.org/r/20200910070331.3358048-6-davidgow@google.com Signed-off-by: Linus Torvalds Signed-off-by: Eric Biggers --- mm/kasan/report.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 6bcfb01ba0386..5b421f8433488 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -172,7 +172,7 @@ static void kasan_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 && !test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags)) panic("panic_on_warn set ...\n"); kasan_enable_current(); }