From: Petr Machata <pmachata@redhat.com>
Date: Mon, 16 Feb 2009 16:57:02 +0000 (+0100)
Subject: Check DW_OP_addr relocations
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a78153661ef0d5ece7284d887aef4d56b7ea0d33;p=thirdparty%2Felfutils.git

Check DW_OP_addr relocations

* and add support for address-like relocations in general
---

diff --git a/src/dwarflint.c b/src/dwarflint.c
index 09da37fd7..65df84775 100644
--- a/src/dwarflint.c
+++ b/src/dwarflint.c
@@ -2447,16 +2447,23 @@ relocate_one (struct relocation_data *reloc, GElf_Rela *rela,
       uint64_t section_index = symbol->st_shndx;
 
       /* It's target value, not section offset.  */
-      if (offset_into == rel_value)
+      if (offset_into == rel_value
+	  || offset_into == rel_address)
 	{
-	  /* If a target value is what's expected, then complain
-	     if it's not either SHN_ABS, an SHF_ALLOC section, or
-	     SHN_UNDEF.  */
-	  if (section_index != SHN_ABS && section_index != SHN_UNDEF)
+	  /* If a target value is what's expected, then complain if
+	     it's not either SHN_ABS, an SHF_ALLOC section, or
+	     SHN_UNDEF.  For data forms of address_size, an SHN_UNDEF
+	     reloc is acceptable, otherwise reject it.  */
+	  if (!(section_index == SHN_ABS
+		|| (offset_into == rel_address && section_index == SHN_UNDEF)))
 	    {
-	      Elf_Scn *scn = elf_getscn (elf, section_index);
+	      Elf_Scn *scn;
 	      GElf_Shdr shdr_mem, *shdr;
-	      if (scn == NULL)
+	      if (offset_into != rel_address && section_index == SHN_UNDEF)
+		wr_error (&reloc_where,
+			    ": relocation of an address is formed against SHN_UNDEF section"
+			    " (index %" PRId64 ").\n", section_index);
+	      else if ((scn = elf_getscn (elf, section_index)) == NULL)
 		wr_error (&reloc_where,
 			  ": couldn't obtain associated section #%" PRId64 ".\n",
 			  section_index);
@@ -2485,8 +2492,9 @@ relocate_one (struct relocation_data *reloc, GElf_Rela *rela,
 		? strdup (where_fmt (&WHERE (id, NULL), NULL)) : "(?)";
 	      char *wh2 = strdup (where_fmt (&WHERE (offset_into, NULL), NULL));
 	      wr_error (&reloc_where,
-			": relocation references section %s, but %s was expected.\n",
-			wh1, wh2);
+			": relocation references section %s, but %s was expected"
+			" (section index: %" PRId64 ").\n",
+			wh1, wh2, section_index);
 	      free (wh2);
 	      if (id != sec_invalid)
 		free (wh1);
@@ -2587,6 +2595,9 @@ reloc_target_loc (uint8_t opcode)
     case DW_OP_call4:
       return sec_info;
 
+    case DW_OP_addr:
+      return rel_address;
+
     case DW_OP_call_ref:
       assert (!"Can't handle call_ref!");
     };
diff --git a/src/dwarflint.h b/src/dwarflint.h
index 290b4dd66..b05ee9927 100644
--- a/src/dwarflint.h
+++ b/src/dwarflint.h
@@ -24,6 +24,7 @@ extern "C"
     rel_value,		/* For relocations, this denotes that the
 			   relocation is applied to taget value, not a
 			   section offset.  */
+    rel_address,	/* Same as above, but for addresses.  */
 
     /* Debuginfo sections:  */
     sec_info,