From 8cd4d5046d7cb1bc16f01e77a5ff50eca8d9da3d Mon Sep 17 00:00:00 2001

From: Jan Kratochvil <jan.kratochvil@redhat.com>

Date: Sat, 1 Aug 2020 10:45:47 +0200

Subject: [PATCH 3/6] debugedit: Fix missing relocation of .debug_types

 section.

---

 tools/debugedit.c | 123 ++++++++++++++++++++++++++++++----------------

 1 file changed, 80 insertions(+), 43 deletions(-)

diff --git a/tools/debugedit.c b/tools/debugedit.c

index cad0cc349..87c1cd622 100644

--- a/tools/debugedit.c

+++ b/tools/debugedit.c

@@ -433,7 +433,8 @@ typedef struct debug_section

     int sec, relsec;

     REL *relbuf;

     REL *relend;

-    struct debug_section *next; /* Only happens for COMDAT .debug_macro.  */

+    /* Only happens for COMDAT .debug_macro and .debug_types.  */

+    struct debug_section *next;

   } debug_section;

 static debug_section debug_sections[] =

@@ -1269,7 +1270,9 @@ static int dirty_elf;

 static void

 dirty_section (unsigned int sec)

 {

-  elf_flagdata (debug_sections[sec].elf_data, ELF_C_SET, ELF_F_DIRTY);

+  for (struct debug_section *secp = &debug_sections[sec]; secp != NULL;

+       secp = secp->next)

+    elf_flagdata (secp->elf_data, ELF_C_SET, ELF_F_DIRTY);

   dirty_elf = 1;

 }

@@ -1469,12 +1472,7 @@ read_dwarf2_line (DSO *dso, uint32_t off, char *comp_dir)

   if (get_line_table (dso, off, &table) == false

       || table == NULL)

-    {

-      if (table != NULL)

-	error (0, 0, ".debug_line offset 0x%x referenced multiple times",

-	       off);

-      return false;

-    }

+    return false;

   /* Skip to the directory table. The rest of the header has already

      been read and checked by get_line_table. */

@@ -1965,22 +1963,25 @@ line_rel_cmp (const void *a, const void *b)

 }

 static int

-edit_info (DSO *dso, int phase)

+edit_info (DSO *dso, int phase, struct debug_section *sec)

 {

   unsigned char *ptr, *endcu, *endsec;

   uint32_t value;

   htab_t abbrev;

   struct abbrev_tag tag, *t;

-  ptr = debug_sections[DEBUG_INFO].data;

-  setup_relbuf(dso, &debug_sections[DEBUG_INFO], &reltype);

-  endsec = ptr + debug_sections[DEBUG_INFO].size;

+  ptr = sec->data;

+  if (ptr == NULL)

+    return 0;

+

+  setup_relbuf(dso, sec, &reltype);

+  endsec = ptr + sec->size;

   while (ptr < endsec)

     {

-      if (ptr + 11 > endsec)

+      if (ptr + (sec == &debug_sections[DEBUG_INFO] ? 11 : 23) > endsec)

 	{

-	  error (0, 0, "%s: .debug_info CU header too small",

-		 dso->filename);

+	  error (0, 0, "%s: %s CU header too small",

+		 dso->filename, sec->name);

 	  return 1;

 	}

@@ -1994,7 +1995,7 @@ edit_info (DSO *dso, int phase)

       if (endcu > endsec)

 	{

-	  error (0, 0, "%s: .debug_info too small", dso->filename);

+	  error (0, 0, "%s: %s too small", dso->filename, sec->name);

 	  return 1;

 	}

@@ -2034,6 +2035,9 @@ edit_info (DSO *dso, int phase)

 	  return 1;

 	}

+      if (sec != &debug_sections[DEBUG_INFO])

+	ptr += 12; /* Skip type_signature and type_offset.  */

+

       abbrev = read_abbrev (dso,

 			    debug_sections[DEBUG_ABBREV].data + value);

       if (abbrev == NULL)

@@ -2095,7 +2099,7 @@ edit_dwarf2 (DSO *dso)

 		  struct debug_section *debug_sec = &debug_sections[j];

 		  if (debug_sections[j].data)

 		    {

-		      if (j != DEBUG_MACRO)

+		      if (j != DEBUG_MACRO && j != DEBUG_TYPES)

 			{

 			  error (0, 0, "%s: Found two copies of %s section",

 				 dso->filename, name);

@@ -2103,22 +2107,21 @@ edit_dwarf2 (DSO *dso)

 			}

 		      else

 			{

-			  /* In relocatable files .debug_macro might

-			     appear multiple times as COMDAT

-			     section.  */

+			  /* In relocatable files .debug_macro and .debug_types

+			     might appear multiple times as COMDAT section.  */

 			  struct debug_section *sec;

 			  sec = calloc (sizeof (struct debug_section), 1);

 			  if (sec == NULL)

 			    error (1, errno,

-				   "%s: Could not allocate more macro sections",

-				   dso->filename);

-			  sec->name = ".debug_macro";

+				   "%s: Could not allocate more %s sections",

+				   dso->filename, name);

+			  sec->name = name;

-			  struct debug_section *macro_sec = debug_sec;

-			  while (macro_sec->next != NULL)

-			    macro_sec = macro_sec->next;

+			  struct debug_section *multi_sec = debug_sec;

+			  while (multi_sec->next != NULL)

+			    multi_sec = multi_sec->next;

-			  macro_sec->next = sec;

+			  multi_sec->next = sec;

 			  debug_sec = sec;

 			}

 		    }

@@ -2155,23 +2158,23 @@ edit_dwarf2 (DSO *dso)

 			  + (dso->shdr[i].sh_type == SHT_RELA),

 			  debug_sections[j].name) == 0)

 	 	{

-		  if (j == DEBUG_MACRO)

+		  if (j == DEBUG_MACRO || j == DEBUG_TYPES)

 		    {

 		      /* Pick the correct one.  */

 		      int rel_target = dso->shdr[i].sh_info;

-		      struct debug_section *macro_sec = &debug_sections[j];

-		      while (macro_sec != NULL)

+		      struct debug_section *multi_sec = &debug_sections[j];

+		      while (multi_sec != NULL)

 			{

-			  if (macro_sec->sec == rel_target)

+			  if (multi_sec->sec == rel_target)

 			    {

-			      macro_sec->relsec = i;

+			      multi_sec->relsec = i;

 			      break;

 			    }

-			  macro_sec = macro_sec->next;

+			  multi_sec = multi_sec->next;

 			}

-		      if (macro_sec == NULL)

-			error (0, 1, "No .debug_macro reloc section: %s",

-			       dso->filename);

+		      if (multi_sec == NULL)

+			error (0, 1, "No %s reloc section: %s",

+			       debug_sections[j].name, dso->filename);

 		    }

 		  else

 		    debug_sections[j].relsec = i;

@@ -2203,12 +2206,10 @@ edit_dwarf2 (DSO *dso)

   if (debug_sections[DEBUG_INFO].data == NULL)

     return 0;

-  unsigned char *ptr, *endcu, *endsec;

-  uint32_t value;

-  htab_t abbrev;

-  struct abbrev_tag tag, *t;

+  unsigned char *ptr, *endsec;

   int phase;

   bool info_rel_updated = false;

+  bool types_rel_updated = false;

   bool macro_rel_updated = false;

   for (phase = 0; phase < 2; phase++)

@@ -2221,13 +2222,26 @@ edit_dwarf2 (DSO *dso)

 	break;

       rel_updated = false;

-      if (edit_info (dso, phase))

-       return 1;

+      if (edit_info (dso, phase, &debug_sections[DEBUG_INFO]))

+	return 1;

       /* Remember whether any .debug_info relocations might need

 	 to be updated. */

       info_rel_updated = rel_updated;

+      rel_updated = false;

+      struct debug_section *types_sec = &debug_sections[DEBUG_TYPES];

+      while (types_sec != NULL)

+	{

+	  if (edit_info (dso, phase, types_sec))

+	    return 1;

+	  types_sec = types_sec->next;

+	}

+

+      /* Remember whether any .debug_types relocations might need

+	 to be updated. */

+      types_rel_updated = rel_updated;

+

       /* We might have to recalculate/rewrite the debug_line

 	 section.  We need to do that before going into phase one

 	 so we have all new offsets.  We do this separately from

@@ -2475,8 +2489,11 @@ edit_dwarf2 (DSO *dso)

   /* After phase 1 we might have rewritten the debug_info with

      new strp, strings and/or linep offsets.  */

-  if (need_strp_update || need_string_replacement || need_stmt_update)

+  if (need_strp_update || need_string_replacement || need_stmt_update) {

     dirty_section (DEBUG_INFO);

+    if (debug_sections[DEBUG_TYPES].data != NULL)

+      dirty_section (DEBUG_TYPES);

+  }

   if (need_strp_update || need_stmt_update)

     dirty_section (DEBUG_MACRO);

   if (need_stmt_update)

@@ -2485,6 +2502,15 @@ edit_dwarf2 (DSO *dso)

   /* Update any relocations addends we might have touched. */

   if (info_rel_updated)

     update_rela_data (dso, &debug_sections[DEBUG_INFO]);

+  if (types_rel_updated)

+    {

+      struct debug_section *types_sec = &debug_sections[DEBUG_TYPES];

+      while (types_sec != NULL)

+	{

+	  update_rela_data (dso, types_sec);

+	  types_sec = types_sec->next;

+	}

+    }

   if (macro_rel_updated)

     {

@@ -3037,6 +3063,17 @@ main (int argc, char *argv[])

       macro_sec = next;

     }

+  /* In case there were multiple (COMDAT) .debug_types sections,

+     free them.  */

+  struct debug_section *types_sec = &debug_sections[DEBUG_TYPES];

+  types_sec = types_sec->next;

+  while (types_sec != NULL)

+    {

+      struct debug_section *next = types_sec->next;

+      free (types_sec);

+      types_sec = next;

+    }

+

   poptFreeContext (optCon);

   return 0;

-- 

2.18.4