From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753456AbaAUUcu (ORCPT ); Tue, 21 Jan 2014 15:32:50 -0500 Received: from smtp.outflux.net ([198.145.64.163]:46091 "EHLO smtp.outflux.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753054AbaAUUct (ORCPT ); Tue, 21 Jan 2014 15:32:49 -0500 Date: Tue, 21 Jan 2014 12:32:23 -0800 From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Kees Cook , Michael Davidson , Cong Ding Subject: [PATCH] x86, relocs: add manual debug mode Message-ID: <20140121203223.GA12649@www.outflux.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-HELO: www.outflux.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michael Davidson Improve the debuggability of relocations output. When trying to compare the output between different linkers, it's handy to be able to see the section names in output. Signed-off-by: Michael Davidson Signed-off-by: Kees Cook --- arch/x86/tools/relocs.c | 30 +++++++++++++++++++++++++++++- arch/x86/tools/relocs.h | 7 ++++--- arch/x86/tools/relocs_common.c | 16 ++++++++++++---- 3 files changed, 45 insertions(+), 8 deletions(-) diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index 11f9285a2ff6..cfbdbdb4e173 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -1025,6 +1025,29 @@ static void emit_relocs(int as_text, int use_real_mode) } } +/* + * As an aid to debugging problems with different linkers + * print summary information about the relocs. + * Since different linkers tend to emit the sections in + * different orders we use the section names in the output. + */ +static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym, + const char *symname) +{ + printf("%s\t%s\t%s\t%s\n", + sec_name(sec->shdr.sh_info), + rel_type(ELF_R_TYPE(rel->r_info)), + symname, + sec_name(sym->st_shndx)); + return 0; +} + +static void print_reloc_info(void) +{ + printf("reloc section\treloc type\tsymbol\tsymbol section\n"); + walk_relocs(do_reloc_info); +} + #if ELF_BITS == 64 # define process process_64 #else @@ -1032,7 +1055,8 @@ static void emit_relocs(int as_text, int use_real_mode) #endif void process(FILE *fp, int use_real_mode, int as_text, - int show_absolute_syms, int show_absolute_relocs) + int show_absolute_syms, int show_absolute_relocs, + int show_reloc_info) { regex_init(use_real_mode); read_ehdr(fp); @@ -1050,5 +1074,9 @@ void process(FILE *fp, int use_real_mode, int as_text, print_absolute_relocs(); return; } + if (show_reloc_info) { + print_reloc_info(); + return; + } emit_relocs(as_text, use_real_mode); } diff --git a/arch/x86/tools/relocs.h b/arch/x86/tools/relocs.h index 07cdb1eca4fa..f59590645b68 100644 --- a/arch/x86/tools/relocs.h +++ b/arch/x86/tools/relocs.h @@ -29,8 +29,9 @@ enum symtype { }; void process_32(FILE *fp, int use_real_mode, int as_text, - int show_absolute_syms, int show_absolute_relocs); + int show_absolute_syms, int show_absolute_relocs, + int show_reloc_info); void process_64(FILE *fp, int use_real_mode, int as_text, - int show_absolute_syms, int show_absolute_relocs); - + int show_absolute_syms, int show_absolute_relocs, + int show_reloc_info); #endif /* RELOCS_H */ diff --git a/arch/x86/tools/relocs_common.c b/arch/x86/tools/relocs_common.c index 44d396823a53..acab636bcb34 100644 --- a/arch/x86/tools/relocs_common.c +++ b/arch/x86/tools/relocs_common.c @@ -11,12 +11,13 @@ void die(char *fmt, ...) static void usage(void) { - die("relocs [--abs-syms|--abs-relocs|--text|--realmode] vmlinux\n"); + die("relocs [--abs-syms|--abs-relocs|--reloc-info|--text|--realmode]" \ + " vmlinux\n"); } int main(int argc, char **argv) { - int show_absolute_syms, show_absolute_relocs; + int show_absolute_syms, show_absolute_relocs, show_reloc_info; int as_text, use_real_mode; const char *fname; FILE *fp; @@ -25,6 +26,7 @@ int main(int argc, char **argv) show_absolute_syms = 0; show_absolute_relocs = 0; + show_reloc_info = 0; as_text = 0; use_real_mode = 0; fname = NULL; @@ -39,6 +41,10 @@ int main(int argc, char **argv) show_absolute_relocs = 1; continue; } + if (strcmp(arg, "--reloc-info") == 0) { + show_reloc_info = 1; + continue; + } if (strcmp(arg, "--text") == 0) { as_text = 1; continue; @@ -67,10 +73,12 @@ int main(int argc, char **argv) rewind(fp); if (e_ident[EI_CLASS] == ELFCLASS64) process_64(fp, use_real_mode, as_text, - show_absolute_syms, show_absolute_relocs); + show_absolute_syms, show_absolute_relocs, + show_reloc_info); else process_32(fp, use_real_mode, as_text, - show_absolute_syms, show_absolute_relocs); + show_absolute_syms, show_absolute_relocs, + show_reloc_info); fclose(fp); return 0; } -- 1.7.9.5 -- Kees Cook Chrome OS Security