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=-26.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 93F5FC2BA1E for ; Mon, 15 Mar 2021 16:59:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6566164DE2 for ; Mon, 15 Mar 2021 16:59:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234091AbhCOQ65 (ORCPT ); Mon, 15 Mar 2021 12:58:57 -0400 Received: from linux.microsoft.com ([13.77.154.182]:51084 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232220AbhCOQ6Q (ORCPT ); Mon, 15 Mar 2021 12:58:16 -0400 Received: from x64host.home (unknown [47.187.194.202]) by linux.microsoft.com (Postfix) with ESMTPSA id 8650420B26FE; Mon, 15 Mar 2021 09:58:15 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 8650420B26FE DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1615827496; bh=jheyVZ/lUkxf4Ht1TtTUL0sobQn62YR0CVwzSLRcRdA=; h=From:To:Subject:Date:In-Reply-To:References:From; b=QJ42h8pS1O+0cURPnA4fdCqupwkpfS259xG/1wglI00VOExTU1uQoa03R3XOzBYrb lkMnRDAYrogw1NMDoZ7NnPHshtec1eFkIan34A5ppztxARo+x+Rg7Y2tjMJDA+p1am cYsgch6qRqbr/azncTfOJfhMUWYyvtO0UgZt21SI= From: madvenka@linux.microsoft.com To: broonie@kernel.org, mark.rutland@arm.com, jpoimboe@redhat.com, jthierry@redhat.com, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, madvenka@linux.microsoft.com Subject: [RFC PATCH v2 6/8] arm64: Check the return PC of every stack frame Date: Mon, 15 Mar 2021 11:57:58 -0500 Message-Id: <20210315165800.5948-7-madvenka@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210315165800.5948-1-madvenka@linux.microsoft.com> References: <5997dfe8d261a3a543667b83c902883c1e4bd270> <20210315165800.5948-1-madvenka@linux.microsoft.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Madhavan T. Venkataraman" If a function encountered in a stack trace is not a valid kernel text address, the stack trace is considered unreliable. Mark the stack trace as not reliable. Signed-off-by: Madhavan T. Venkataraman --- arch/arm64/kernel/stacktrace.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index 594806a0c225..358aae3906d7 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -101,6 +101,16 @@ static void check_if_reliable(unsigned long fp, struct stackframe *frame, } } #endif + + /* + * A NULL or invalid return address probably means there's some + * generated code which __kernel_text_address() doesn't know about. + * Mark the stack trace as not reliable. + */ + if (!__kernel_text_address(frame->pc)) { + frame->reliable = false; + return; + } } /* -- 2.25.1