From: Petr Machata <pmachata@redhat.com>
Date: Thu, 17 Mar 2011 09:51:58 +0000 (+0100)
Subject: dwarflint: Check that .shstrtab is sound
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=66a96a2d8162601ed99dc04c6fa6ecd6ee14a7f4;p=thirdparty%2Felfutils.git

dwarflint: Check that .shstrtab is sound
---

diff --git a/dwarflint/Makefile.am b/dwarflint/Makefile.am
index 7c0a9b2f9..3da11ac0f 100644
--- a/dwarflint/Makefile.am
+++ b/dwarflint/Makefile.am
@@ -130,7 +130,8 @@ EXTRA_DIST = $(EXTRA_TESTS) \
 	tests/garbage-8.bz2 \
 	tests/garbage-9.bz2 \
 	tests/garbage-10.bz2 \
-	tests/garbage-11.bz2
+	tests/garbage-11.bz2 \
+	tests/garbage-12.bz2
 
 installed_TESTS_ENVIRONMENT = libdir=$(DESTDIR)$(libdir) \
 			      bindir=$(DESTDIR)$(bindir) \
diff --git a/dwarflint/sections.cc b/dwarflint/sections.cc
index add26b894..d5736c4be 100644
--- a/dwarflint/sections.cc
+++ b/dwarflint/sections.cc
@@ -1,5 +1,5 @@
 /* Low-level section handling.
-   Copyright (C) 2009, 2010 Red Hat, Inc.
+   Copyright (C) 2009, 2010, 2011 Red Hat, Inc.
    This file is part of Red Hat elfutils.
 
    Red Hat elfutils is free software; you can redistribute it and/or modify
@@ -252,6 +252,17 @@ namespace
 
     bool check_rel = true;
 
+    /* Try to obtain .shstrtab, which we will need in following.  If
+       we fail, elf is broken.  */
+    Elf_Scn *shstrscn = elf_getscn (elf, file->ehdr.e_shstrndx);
+    if (shstrscn == NULL || elf_rawdata (shstrscn, NULL) == NULL)
+      {
+      invalid_elf:
+	wr_error () << "Broken ELF: " << elf_errmsg (-1) << "."
+		    << std::endl;
+	goto close_and_out;
+      }
+
     for (Elf_Scn *scn = NULL; (scn = elf_nextscn (elf, scn)); )
       {
 	REALLOC (file, sec);
@@ -260,15 +271,11 @@ namespace
 
 	GElf_Shdr *shdr = gelf_getshdr (scn, &cursec->shdr);
 	if (shdr == NULL)
-	  {
-	  invalid_elf:
-	    wr_error () << "Broken ELF: " << elf_errmsg (-1) << "."
-			<< std::endl;
-	    goto close_and_out;
-	  }
+	  goto invalid_elf;
 
 	const char *scnname = elf_strptr (elf, file->ehdr.e_shstrndx,
 					  shdr->sh_name);
+	// Validate the section name
 	if (scnname == NULL)
 	  goto invalid_elf;
 
diff --git a/dwarflint/tests/garbage-12.bz2 b/dwarflint/tests/garbage-12.bz2
new file mode 100644
index 000000000..a38e928e5
Binary files /dev/null and b/dwarflint/tests/garbage-12.bz2 differ
diff --git a/dwarflint/tests/run-bad.sh b/dwarflint/tests/run-bad.sh
index 46678f0f7..41c56a5f1 100755
--- a/dwarflint/tests/run-bad.sh
+++ b/dwarflint/tests/run-bad.sh
@@ -30,7 +30,7 @@ srcdir=$srcdir/tests
 testfiles hello.bad-1 hello.bad-3 empty-1 \
     garbage-1 garbage-2 garbage-3 garbage-4 \
     garbage-5 garbage-6 garbage-7 garbage-8 \
-    garbage-9 garbage-10 garbage-11
+    garbage-9 garbage-10 garbage-11 garbage-12
 
 testrun_compare ./dwarflint hello.bad-1 <<EOF
 error: .debug_info: DIE 0x83: abbrev section at 0x0 doesn't contain code 83.
@@ -116,3 +116,9 @@ error: .rela.debug_info: offset 0x3600: invalid relocation 256 (<INVALID RELOC>)
 error: .debug_line: table 0: header claims that it has a size of 542, but in fact it has a size of 30.
 error: .debug_info: DIE 0xb (abbr. attribute 0xa): unresolved reference to .debug_line table 0x0.
 EOF
+
+testrun_compare ./dwarflint garbage-12 <<EOF
+error: Broken ELF: invalid section header.
+error: .debug_abbrev: data not found.
+error: .debug_info: data not found.
+EOF