From: Sami Tolvanen <samitolvanen@google.com>
Date: Tue, 21 Apr 2020 18:25:01 +0000 (-0700)
Subject: objtool: Use sh_info to find the base for .rela sections
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1e968bf5caf65eff3f080102879aaa5440c261b6;p=linux.git

objtool: Use sh_info to find the base for .rela sections

ELF doesn't require .rela section names to match the base section. Use
the section index in sh_info to find the section instead of looking it
up by name.

LLD, for example, generates a .rela section that doesn't match the base
section name when we merge sections in a linker script for a binary
compiled with -ffunction-sections.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
---

diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index f953d3a15612a..5bc259c9d892c 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -508,7 +508,7 @@ static int read_relas(struct elf *elf)
 		if (sec->sh.sh_type != SHT_RELA)
 			continue;
 
-		sec->base = find_section_by_name(elf, sec->name + 5);
+		sec->base = find_section_by_index(elf, sec->sh.sh_info);
 		if (!sec->base) {
 			WARN("can't find base section for rela section %s",
 			     sec->name);