From patchwork Fri Jun 19 14:32:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 223665 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 567B7C433E1 for ; Fri, 19 Jun 2020 16:45:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 283DC20732 for ; Fri, 19 Jun 2020 16:45:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592585155; bh=LM/du8b8FjrYi1EUgb3XJShtRGgCq7C3Ef2V21ibtII=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PiMPG28MVLpUccMfMYuOLyuias4PcF0/n/9WLDzUkT66sWtPQNZbqkPu+TWJV//eV GYzZ0Y3uhQwzalIMkiDiJpLSi9IXnklAzU9XuN5LO3h0tvUrvVVjiYRwTRiR+eeBx/ 2WxNRt8rhq2BeRdaZSYu/qVKs5Ma30oZmFgeAjUQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388320AbgFSQpr (ORCPT ); Fri, 19 Jun 2020 12:45:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:60856 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388324AbgFSOmD (ORCPT ); Fri, 19 Jun 2020 10:42:03 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 4489121527; Fri, 19 Jun 2020 14:42:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592577723; bh=LM/du8b8FjrYi1EUgb3XJShtRGgCq7C3Ef2V21ibtII=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PHnLZiZ4MS23H2UZmZ0mOBSI7NxogEazxpceEBPOri1A/1+UDfbdzwLPBvMpciM7i xNEBwxd7NYHecEZ3WNQ6lE6BIczrlYV42fvk7qmsXQM3OZJk0ySDdfzvYLhRhPjnFL uE1/Ovn8Tui6YmvRnhJ2Ntez6Gm1uUC1yjbwo4Bo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julien Thierry , "Peter Zijlstra (Intel)" , Miroslav Benes , Josh Poimboeuf , Ingo Molnar , Sasha Levin Subject: [PATCH 4.9 056/128] objtool: Ignore empty alternatives Date: Fri, 19 Jun 2020 16:32:30 +0200 Message-Id: <20200619141623.160513124@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141620.148019466@linuxfoundation.org> References: <20200619141620.148019466@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Julien Thierry [ Upstream commit 7170cf47d16f1ba29eca07fd818870b7af0a93a5 ] The .alternatives section can contain entries with no original instructions. Objtool will currently crash when handling such an entry. Just skip that entry, but still give a warning to discourage useless entries. Signed-off-by: Julien Thierry Acked-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- tools/objtool/check.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index b0b8ba9b800c..c7399d7f4bc7 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -778,6 +778,12 @@ static int add_special_section_alts(struct objtool_file *file) } if (special_alt->group) { + if (!special_alt->orig_len) { + WARN_FUNC("empty alternative entry", + orig_insn->sec, orig_insn->offset); + continue; + } + ret = handle_group_alt(file, special_alt, orig_insn, &new_insn); if (ret)