Fix an illegal memory access when creating DLLs.

	PR 29006
	* pe-dll.c (dll_name): Delete, replacing with..
	(dll_filename): ..this, moved earlier in file.
	(generate_edata): Delete parameters.  Don't set up dll_name here..
	(pe_process_import_defs): ..instead set up dll_filename and
	dll_symname here before returning.
	(dll_symname_len): Delete write-only variable.
	(pe_dll_generate_implib): Don't set up dll_symname here.

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 7b9fdc837ca6642d9a2a2a3b8daa1aa750283887..bcc1b3b7b5614f867c256a85b3fb3c5af74d8809 100644 (file)
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,14 @@
+2022-05-12  Alan Modra  <amodra@gmail.com>
+
+       PR 29006
+       * pe-dll.c (dll_name): Delete, replacing with..
+       (dll_filename): ..this, moved earlier in file.
+       (generate_edata): Delete parameters.  Don't set up dll_name here..
+       (pe_process_import_defs): ..instead set up dll_filename and
+       dll_symname here before returning.
+       (dll_symname_len): Delete write-only variable.
+       (pe_dll_generate_implib): Don't set up dll_symname here.
+
 2022-05-03  Nick Clifton  <nickc@redhat.com>
 
        PR 29101

diff --git a/ld/pe-dll.c b/ld/pe-dll.c
index ed68f66a95b20a432c95d81bcea3994de24b2a71..4cf8ed23672270ce62e1595dbf5abda1135bbf2d 100644 (file)
--- a/ld/pe-dll.c
+++ b/ld/pe-dll.c
@@ -505,7 +505,7 @@ static int export_table_size;
 static int count_exported;
 static int count_exported_byname;
 static int count_with_ordinals;
-static const char *dll_name;
+static const char *dll_filename;
 static int min_ordinal, max_ordinal;
 static int *exported_symbols;
 
@@ -1066,25 +1066,13 @@ build_filler_bfd (int include_edata)
 /* Gather all the exported symbols and build the .edata section.  */
 
 static void
-generate_edata (bfd *abfd, struct bfd_link_info *info ATTRIBUTE_UNUSED)
+generate_edata (void)
 {
   int i, next_ordinal;
   int name_table_size = 0;
-  const char *dlnp;
 
   /* First, we need to know how many exported symbols there are,
      and what the range of ordinals is.  */
-  if (pe_def_file->name)
-    dll_name = pe_def_file->name;
-  else
-    {
-      dll_name = bfd_get_filename (abfd);
-
-      for (dlnp = dll_name; *dlnp; dlnp++)
-       if (*dlnp == '\\' || *dlnp == '/' || *dlnp == ':')
-         dll_name = dlnp + 1;
-    }
-
   if (count_with_ordinals && max_ordinal > count_exported)
     {
       if (min_ordinal > max_ordinal - count_exported + 1)
@@ -1159,7 +1147,7 @@ generate_edata (bfd *abfd, struct bfd_link_info *info ATTRIBUTE_UNUSED)
              + 4 * export_table_size           /* addresses */
              + 4 * count_exported_byname       /* name ptrs */
              + 2 * count_exported_byname       /* ordinals */
-             + name_table_size + strlen (dll_name) + 1);
+             + name_table_size + strlen (dll_filename) + 1);
 }
 
 /* Fill the exported symbol offsets. The preliminary work has already
@@ -1232,7 +1220,7 @@ fill_edata (bfd *abfd, struct bfd_link_info *info ATTRIBUTE_UNUSED)
     }
 
   bfd_put_32 (abfd, ERVA (enamestr), edata_d + 12);
-  strcpy (enamestr, dll_name);
+  strcpy (enamestr, dll_filename);
   enamestr += strlen (enamestr) + 1;
   bfd_put_32 (abfd, min_ordinal, edata_d + 16);
   bfd_put_32 (abfd, export_table_size, edata_d + 20);
@@ -1971,9 +1959,7 @@ pe_dll_generate_def_file (const char *pe_out_def_filename)
 static asymbol **symtab;
 static int symptr;
 static int tmp_seq;
-static const char *dll_filename;
 static char *dll_symname;
-static int dll_symname_len;
 
 #define UNDSEC bfd_und_section_ptr
 
@@ -2835,7 +2821,8 @@ pe_create_import_fixup (arelent *rel, asection *s, bfd_vma addend, char *name,
        printf ("creating runtime pseudo-reloc entry for %s (addend=%d)\n",
                fixup_name, (int) addend);
 
-      b = make_runtime_pseudo_reloc (name, fixup_name, addend, rel->howto->bitsize,
+      b = make_runtime_pseudo_reloc (name, fixup_name, addend,
+                                    rel->howto->bitsize,
                                     link_info.output_bfd);
       add_bfd_to_link (b, bfd_get_filename (b), &link_info);
 
@@ -2861,13 +2848,6 @@ pe_dll_generate_implib (def_file *def, const char *impfilename, struct bfd_link_
   bfd *ibfd;
   bfd *head = 0;
 
-  dll_filename = (def->name) ? def->name : dll_name;
-  dll_symname = xstrdup (dll_filename);
-  dll_symname_len = strlen (dll_symname);
-  for (i = 0; dll_symname[i]; i++)
-    if (!ISALNUM (dll_symname[i]))
-      dll_symname[i] = '_';
-
   unlink_if_ordinary (impfilename);
 
   outarch = bfd_openw (impfilename, 0);
@@ -2995,8 +2975,7 @@ pe_dll_generate_implib (def_file *def, const char *impfilename, struct bfd_link_
          }
       }
 
-      n = make_one (def->exports + i, outarch,
-                   ! (def->exports + i)->flag_data);
+      n = make_one (def->exports + i, outarch, !(def->exports + i)->flag_data);
       n->archive_next = head;
       head = n;
       def->exports[i].internal_name = internal;
@@ -3208,128 +3187,145 @@ add_bfd_to_link (bfd *abfd, const char *name, struct bfd_link_info *linfo)
 void
 pe_process_import_defs (bfd *output_bfd, struct bfd_link_info *linfo)
 {
-  int i, j;
-  def_file_module *module;
-  def_file_import *imp;
-
   pe_dll_id_target (bfd_get_target (output_bfd));
 
-  if (!pe_def_file)
-    return;
-
-  imp = pe_def_file->imports;
-
-  pe_create_undef_table ();
-
-  for (module = pe_def_file->modules; module; module = module->next)
+  if (pe_def_file)
     {
-      int do_this_dll = 0;
+      int i, j;
+      def_file_module *module;
+      def_file_import *imp;
 
-      for (i = 0; i < pe_def_file->num_imports && imp[i].module != module; i++)
-       ;
-      if (i >= pe_def_file->num_imports)
-       continue;
+      imp = pe_def_file->imports;
 
-      dll_filename = module->name;
-      dll_symname = xstrdup (module->name);
-      dll_symname_len = strlen (dll_symname);
-      for (j = 0; dll_symname[j]; j++)
-       if (!ISALNUM (dll_symname[j]))
-         dll_symname[j] = '_';
+      pe_create_undef_table ();
 
-      for (; i < pe_def_file->num_imports && imp[i].module == module; i++)
+      for (module = pe_def_file->modules; module; module = module->next)
        {
-         def_file_export exp;
-         struct bfd_link_hash_entry *blhe;
-         int lead_at = (*imp[i].internal_name == '@');
-         /* See if we need this import.  */
-         size_t len = strlen (imp[i].internal_name);
-         char *name = xmalloc (len + 2 + 6);
-         bool include_jmp_stub = false;
-         bool is_cdecl = false;
-         bool is_undef = false;
-
-         if (!lead_at && strchr (imp[i].internal_name, '@') == NULL)
-             is_cdecl = true;
-
-         if (lead_at)
-           sprintf (name, "%s", imp[i].internal_name);
-         else
-           sprintf (name, "%s%s",U (""), imp[i].internal_name);
+         int do_this_dll = 0;
 
-         blhe = bfd_link_hash_lookup (linfo->hash, name,
-                                      false, false, false);
+         for (i = 0; i < pe_def_file->num_imports; i++)
+           if (imp[i].module == module)
+             break;
+         if (i >= pe_def_file->num_imports)
+           continue;
+
+         dll_filename = module->name;
+         dll_symname = xstrdup (module->name);
+         for (j = 0; dll_symname[j]; j++)
+           if (!ISALNUM (dll_symname[j]))
+             dll_symname[j] = '_';
 
-         /* Include the jump stub for <sym> only if the <sym>
-            is undefined.  */
-         if (!blhe || (blhe && blhe->type != bfd_link_hash_undefined))
+         for (; i < pe_def_file->num_imports && imp[i].module == module; i++)
            {
+             def_file_export exp;
+             struct bfd_link_hash_entry *blhe;
+             int lead_at = (*imp[i].internal_name == '@');
+             /* See if we need this import.  */
+             size_t len = strlen (imp[i].internal_name);
+             char *name = xmalloc (len + 2 + 6);
+             bool include_jmp_stub = false;
+             bool is_cdecl = false;
+             bool is_undef = false;
+
+             if (!lead_at && strchr (imp[i].internal_name, '@') == NULL)
+               is_cdecl = true;
+
              if (lead_at)
-               sprintf (name, "%s%s", "__imp_", imp[i].internal_name);
+               sprintf (name, "%s", imp[i].internal_name);
              else
-               sprintf (name, "%s%s%s", "__imp_", U (""),
-                        imp[i].internal_name);
+               sprintf (name, "%s%s",U (""), imp[i].internal_name);
 
              blhe = bfd_link_hash_lookup (linfo->hash, name,
                                           false, false, false);
-             if (blhe)
-               is_undef = (blhe->type == bfd_link_hash_undefined);
-           }
-         else
-           {
-             include_jmp_stub = true;
-             is_undef = (blhe->type == bfd_link_hash_undefined);
-           }
 
-         if (is_cdecl && (!blhe || (blhe && blhe->type != bfd_link_hash_undefined)))
-           {
-             sprintf (name, "%s%s",U (""), imp[i].internal_name);
-             blhe = pe_find_cdecl_alias_match (linfo, name);
-             include_jmp_stub = true;
-             if (blhe)
-               is_undef = (blhe->type == bfd_link_hash_undefined);
-           }
+             /* Include the jump stub for <sym> only if the <sym>
+                is undefined.  */
+             if (!blhe || (blhe && blhe->type != bfd_link_hash_undefined))
+               {
+                 if (lead_at)
+                   sprintf (name, "%s%s", "__imp_", imp[i].internal_name);
+                 else
+                   sprintf (name, "%s%s%s", "__imp_", U (""),
+                            imp[i].internal_name);
+
+                 blhe = bfd_link_hash_lookup (linfo->hash, name,
+                                              false, false, false);
+                 if (blhe)
+                   is_undef = (blhe->type == bfd_link_hash_undefined);
+               }
+             else
+               {
+                 include_jmp_stub = true;
+                 is_undef = (blhe->type == bfd_link_hash_undefined);
+               }
+
+             if (is_cdecl
+                 && (!blhe || (blhe && blhe->type != bfd_link_hash_undefined)))
+               {
+                 sprintf (name, "%s%s",U (""), imp[i].internal_name);
+                 blhe = pe_find_cdecl_alias_match (linfo, name);
+                 include_jmp_stub = true;
+                 if (blhe)
+                   is_undef = (blhe->type == bfd_link_hash_undefined);
+               }
 
-         free (name);
+             free (name);
 
-         if (is_undef)
-           {
-             bfd *one;
-             /* We do.  */
-             if (!do_this_dll)
+             if (is_undef)
                {
-                 bfd *ar_head = make_head (output_bfd);
-                 add_bfd_to_link (ar_head, bfd_get_filename (ar_head), linfo);
-                 do_this_dll = 1;
+                 bfd *one;
+                 /* We do.  */
+                 if (!do_this_dll)
+                   {
+                     bfd *ar_head = make_head (output_bfd);
+                     add_bfd_to_link (ar_head, bfd_get_filename (ar_head),
+                                      linfo);
+                     do_this_dll = 1;
+                   }
+                 exp.internal_name = imp[i].internal_name;
+                 exp.name = imp[i].name;
+                 exp.its_name = imp[i].its_name;
+                 exp.ordinal = imp[i].ordinal;
+                 exp.hint = exp.ordinal >= 0 ? exp.ordinal : 0;
+                 exp.flag_private = 0;
+                 exp.flag_constant = 0;
+                 exp.flag_data = imp[i].data;
+                 exp.flag_noname = exp.name ? 0 : 1;
+                 one = make_one (&exp, output_bfd,
+                                 !exp.flag_data && include_jmp_stub);
+                 add_bfd_to_link (one, bfd_get_filename (one), linfo);
                }
-             exp.internal_name = imp[i].internal_name;
-             exp.name = imp[i].name;
-             exp.its_name = imp[i].its_name;
-             exp.ordinal = imp[i].ordinal;
-             exp.hint = exp.ordinal >= 0 ? exp.ordinal : 0;
-             exp.flag_private = 0;
-             exp.flag_constant = 0;
-             exp.flag_data = imp[i].data;
-             exp.flag_noname = exp.name ? 0 : 1;
-             one = make_one (&exp, output_bfd, (! exp.flag_data) && include_jmp_stub);
-             add_bfd_to_link (one, bfd_get_filename (one), linfo);
            }
+         if (do_this_dll)
+           {
+             bfd *ar_tail = make_tail (output_bfd);
+             add_bfd_to_link (ar_tail, bfd_get_filename (ar_tail), linfo);
+           }
+
+         free (dll_symname);
        }
-      if (do_this_dll)
+
+      while (undef_count)
        {
-         bfd *ar_tail = make_tail (output_bfd);
-         add_bfd_to_link (ar_tail, bfd_get_filename (ar_tail), linfo);
+         --undef_count;
+         free (udef_table[undef_count].key);
        }
-
-      free (dll_symname);
+      free (udef_table);
     }
 
-  while (undef_count)
+  if (pe_def_file && pe_def_file->name)
+    dll_filename = pe_def_file->name;
+  else
     {
-      --undef_count;
-      free (udef_table[undef_count].key);
+      dll_filename = bfd_get_filename (output_bfd);
+      for (const char *p = dll_filename; *p; p++)
+       if (*p == '\\' || *p == '/' || *p == ':')
+         dll_filename = p + 1;
     }
-  free (udef_table);
+  dll_symname = xstrdup (dll_filename);
+  for (int i = 0; dll_symname[i]; i++)
+    if (!ISALNUM (dll_symname[i]))
+      dll_symname[i] = '_';
 }
 
 /* We were handed a *.DLL file.  Parse it and turn it into a set of
@@ -3629,7 +3625,7 @@ pe_dll_build_sections (bfd *abfd, struct bfd_link_info *info)
       return;
     }
 
-  generate_edata (abfd, info);
+  generate_edata ();
   build_filler_bfd (1);
   pe_output_file_set_long_section_names (filler_bfd);
 }