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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 BA259C0044C for ; Wed, 7 Nov 2018 14:06:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D1012085B for ; Wed, 7 Nov 2018 14:06:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8D1012085B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727714AbeKGXgj (ORCPT ); Wed, 7 Nov 2018 18:36:39 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33608 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726635AbeKGXgj (ORCPT ); Wed, 7 Nov 2018 18:36:39 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 04C43C05D3F7; Wed, 7 Nov 2018 14:06:08 +0000 (UTC) Received: from shodan.usersys.redhat.com (unknown [10.43.17.28]) by smtp.corp.redhat.com (Postfix) with ESMTP id BEAC31001F4C; Wed, 7 Nov 2018 14:06:07 +0000 (UTC) Received: by shodan.usersys.redhat.com (Postfix, from userid 1000) id 171732C1A0C; Wed, 7 Nov 2018 15:06:07 +0100 (CET) From: Artem Savkov To: Josh Poimboeuf Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Artem Savkov Subject: [PATCH] objtool: fix .cold. functions parent symbols search Date: Wed, 7 Nov 2018 15:05:59 +0100 Message-Id: <20181107140559.28504-1-asavkov@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Wed, 07 Nov 2018 14:06:08 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The way it is currently done it is possible for read_symbols() to find the same symbol as parent for ".cold" functions. This leads to a bunch of complications such as func length being set to 0 and a segfault in add_switch_table(). Fix by copying the search string instead of modifying it in place. Signed-off-by: Artem Savkov --- tools/objtool/elf.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 6dbb9fae0f9d..781c8afb29b9 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -298,6 +298,7 @@ static int read_symbols(struct elf *elf) /* Create parent/child links for any cold subfunctions */ list_for_each_entry(sec, &elf->sections, list) { list_for_each_entry(sym, &sec->symbol_list, list) { + char *pname; if (sym->type != STT_FUNC) continue; sym->pfunc = sym->cfunc = sym; @@ -305,9 +306,9 @@ static int read_symbols(struct elf *elf) if (!coldstr) continue; - coldstr[0] = '\0'; - pfunc = find_symbol_by_name(elf, sym->name); - coldstr[0] = '.'; + pname = strndup(sym->name, coldstr - sym->name); + pfunc = find_symbol_by_name(elf, pname); + free(pname); if (!pfunc) { WARN("%s(): can't find parent function", -- 2.17.2