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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 86C3DC54FCC for ; Tue, 21 Apr 2020 22:08:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 627B320724 for ; Tue, 21 Apr 2020 22:08:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="FXX1HOXK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726361AbgDUWI6 (ORCPT ); Tue, 21 Apr 2020 18:08:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726039AbgDUWI4 (ORCPT ); Tue, 21 Apr 2020 18:08:56 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0D40C0610D5 for ; Tue, 21 Apr 2020 15:08:56 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id x2so263836pll.2 for ; Tue, 21 Apr 2020 15:08:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=fVIRB7nPAwO8kLy6VX4zUFaducbG0VpK9IknjM4RI4M=; b=FXX1HOXKJ7NoZpycK1aXAxzvWkUyMHLSvNaa3Af371ceMDmmzoYJ8FRRPn7/kxTIYL qECNrHZdU3kJzO74hxmvqU6+PBsqV4xUPgGyIuec1ifXmuDRRG4PIZA2cZ1qTG9u8GAr OQkvXcv3DI1iNjEwGh+72a6J2s3RCLZozBlS2RdOpJdaV5HJUGFH51ysoysgg5JLuRYz LRCWNOU5cWksQUklXDG4PzmoosDZ5zWF2hUifFwmKW77s7PoRFmLKNi21yHJp6QzGSX/ 9n1vToyVgKB6Q+8iDgXCBs2yT/IRHxmbe02gk+IVv5Bvo6W0ERVFkJDAcHnxoQMcgXXt MKVg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=fVIRB7nPAwO8kLy6VX4zUFaducbG0VpK9IknjM4RI4M=; b=eq5tNQk2xOUk3KvaNg4NvmxvoFfIfQd11odLR71uH+NUf9s8Y9uHO6Gc+sWCVFPtj1 VTffIlH6wx7qUGrqsQIdx6poOkI+iZiCVuMWV2dOUH1HrQw29KSE9OcZ4sKyuf+mDOtR GnEBbxAxqvVFK4pJGIa7CTnHwyfAbGYK3obSbgBrU12HiXf/ml/PJ5Y7rolzOEfzmQ5I 5fQXV62xorNIAhRXT78QDqY4WiwQNzhGyXGDT06bzyH5J7nQGOt5DrjO60KW2G0D8kaW uybAjfaLCIlLEGEV6qaIN7s3lhvF7Juqr4CtmxlTXAVKimdN0ZRGHdP+1DVfDAQgdmly 3rPQ== X-Gm-Message-State: AGi0PuYaHV0xQIDqgCEalL3sOsRd3xdcC3A3ZwCHucL0G95dQE+XHj8F kMgsE3x6130Ql9P+iFhHhdErNAzQwX0owqx00CI= X-Google-Smtp-Source: APiQypL9e8XUj6ZMTAwWNC0wEGQbiIDAdeJIGiAEo/q8Sl4WkumgUPUz6VEo7s8myVHV/2CYLeFSTOrAdrl4jO6vIec= X-Received: by 2002:a63:5009:: with SMTP id e9mr14580502pgb.381.1587506936222; Tue, 21 Apr 2020 15:08:56 -0700 (PDT) Date: Tue, 21 Apr 2020 15:08:42 -0700 In-Reply-To: <20200421220843.188260-1-samitolvanen@google.com> Message-Id: <20200421220843.188260-2-samitolvanen@google.com> Mime-Version: 1.0 References: <20200421180724.245410-1-samitolvanen@google.com> <20200421220843.188260-1-samitolvanen@google.com> X-Mailer: git-send-email 2.26.1.301.g55bc3eb7cb9-goog Subject: [PATCH v2 1/2] objtool: use gelf_getsymshndx to handle >64k sections From: Sami Tolvanen To: Josh Poimboeuf , Peter Zijlstra Cc: Kees Cook , Kristen Carlson Accardi , linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, objtool fails to load the correct section for symbols when the index is greater than SHN_LORESERVE. Use gelf_getsymshndx instead of gelf_getsym to handle >64k sections. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- tools/objtool/elf.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 09ddc8f1def3..887445e87380 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -327,12 +327,14 @@ static int read_sections(struct elf *elf) static int read_symbols(struct elf *elf) { - struct section *symtab, *sec; + struct section *symtab, *symtab_shndx, *sec; struct symbol *sym, *pfunc; struct list_head *entry; struct rb_node *pnode; int symbols_nr, i; char *coldstr; + Elf_Data *shndx_data = NULL; + Elf32_Word shndx; symtab = find_section_by_name(elf, ".symtab"); if (!symtab) { @@ -340,6 +342,10 @@ static int read_symbols(struct elf *elf) return -1; } + symtab_shndx = find_section_by_name(elf, ".symtab_shndx"); + if (symtab_shndx) + shndx_data = symtab_shndx->data; + symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize; for (i = 0; i < symbols_nr; i++) { @@ -353,8 +359,9 @@ static int read_symbols(struct elf *elf) sym->idx = i; - if (!gelf_getsym(symtab->data, i, &sym->sym)) { - WARN_ELF("gelf_getsym"); + if (!gelf_getsymshndx(symtab->data, shndx_data, i, &sym->sym, + &shndx)) { + WARN_ELF("gelf_getsymshndx"); goto err; } @@ -368,10 +375,13 @@ static int read_symbols(struct elf *elf) sym->type = GELF_ST_TYPE(sym->sym.st_info); sym->bind = GELF_ST_BIND(sym->sym.st_info); - if (sym->sym.st_shndx > SHN_UNDEF && - sym->sym.st_shndx < SHN_LORESERVE) { - sym->sec = find_section_by_index(elf, - sym->sym.st_shndx); + if ((sym->sym.st_shndx > SHN_UNDEF && + sym->sym.st_shndx < SHN_LORESERVE) || + (shndx_data && sym->sym.st_shndx == SHN_XINDEX)) { + if (sym->sym.st_shndx != SHN_XINDEX) + shndx = sym->sym.st_shndx; + + sym->sec = find_section_by_index(elf, shndx); if (!sym->sec) { WARN("couldn't find section for symbol %s", sym->name); -- 2.26.1.301.g55bc3eb7cb9-goog