More fixes for reading corrupt ELF files.
authorNick Clifton <nickc@redhat.com>
Wed, 5 Nov 2014 16:19:03 +0000 (16:19 +0000)
committerNick Clifton <nickc@redhat.com>
Wed, 5 Nov 2014 16:19:03 +0000 (16:19 +0000)
PR binutils/15731
* readelf.c (printable_section_name): New function.
(printable_section_name_from_index): New function.
(dump_relocations): Use new function.
(process_program_headers, get_32bit_elf_symbols,
(get_64bit_elf_symbols, process_section_headers,
(process_section_groups, process_relocs, ia64_process_unwind,
(hppa_process_unwind, get_unwind_section_word, decode_arm_unwind,
(arm_process_unwind, process_version_sections,
(process_symbol_table, apply_relocations, get_section_contents,
(dump_section_as_strings, dump_section_as_bytes,
(display_debug_section, process_attributes, process_mips_specific,
(process_mips_specific process_gnu_liblist): Likewise.
(get_unwind_section_word): Check for a missing symbol table.
Replace aborts with error messages.
(arm_process_unwind): Check for a missing string table.
(process_attributes): Check for an attribute length that is too
small.
(process_mips_specific): Check for a corrupt GOT symbol offset.

binutils/ChangeLog
binutils/readelf.c

index 3db190c94948bcc5ca71374f8d8462bbe0e9b4c5..7c3b581e926949248677532e789aba44c6cfc72c 100644 (file)
@@ -1,3 +1,34 @@
+2014-11-05  Nick Clifton  <nickc@redhat.com>
+
+       PR binutils/15731
+       * readelf.c (printable_section_name): New function.
+       (printable_section_name_from_index): New function.
+       (dump_relocations): Use new function.
+       (process_program_headers, get_32bit_elf_symbols,
+       (get_64bit_elf_symbols, process_section_headers,
+       (process_section_groups, process_relocs, ia64_process_unwind,
+       (hppa_process_unwind, get_unwind_section_word, decode_arm_unwind,
+       (arm_process_unwind, process_version_sections,
+       (process_symbol_table, apply_relocations, get_section_contents,
+       (dump_section_as_strings, dump_section_as_bytes,
+       (display_debug_section, process_attributes, process_mips_specific,
+       (process_mips_specific process_gnu_liblist): Likewise.
+       (get_unwind_section_word): Check for a missing symbol table.
+       Replace aborts with error messages.
+       (arm_process_unwind): Check for a missing string table.
+       (process_attributes): Check for an attribute length that is too
+       small.
+       (process_mips_specific): Check for a corrupt GOT symbol offset.
+
+2014-11-05  Nick Clifton  <nickc@redhat.com>
+
+       PR binutils/15733
+       * bucomm.c (is_valid_archive_path): New function.
+       * bucomm.h (is_valid_archive_path): Prototype it.
+       * ar.c (extract_file): Call is_valid_archive_path to verify a
+       member filename before extracting it.
+       * objcopy.c (copy_archive): Likewise.
+
 2014-11-05  Jan-Benedict Glaw  <jbglaw@lug-owl.de>
 
        * readelf.c (process_mips_specific): Fix format string warning.
index 18465e66c5f1dfa96d979c734368c7df5b692adc..089ea13674b4de2632fb5c7513f36ca07de87b5c 100644 (file)
@@ -422,6 +422,7 @@ print_symbol (int width, const char *symbol)
       width = - width;
       extra_padding = TRUE;
     }
+  assert (width != 0);
 
   if (do_wide)
     /* Set the remaining width to a very large value.
@@ -494,6 +495,66 @@ print_symbol (int width, const char *symbol)
   return num_printed;
 }
 
+/* Returns a pointer to a static buffer containing a  printable version of
+   the given section's name.  Like print_symbol, except that it does not try
+   to print multibyte characters, it just interprets them as hex values.  */
+
+static const char *
+printable_section_name (Elf_Internal_Shdr * sec)
+{
+#define MAX_PRINT_SEC_NAME_LEN 128
+  static char  sec_name_buf [MAX_PRINT_SEC_NAME_LEN + 1];
+  const char * name = SECTION_NAME (sec);
+  char *       buf = sec_name_buf;
+  char         c;
+  unsigned int remaining = MAX_PRINT_SEC_NAME_LEN;
+
+  while ((c = * name ++) != 0)
+    {
+      if (ISCNTRL (c))
+       {
+         if (remaining < 2)
+           break;
+         
+         * buf ++ = '^';
+         * buf ++ = c + 0x40;
+         remaining -= 2;
+       }
+      else if (ISPRINT (c))
+       {
+         * buf ++ = c;
+         remaining -= 1;
+       }
+      else
+       {
+         static char hex[17] = "0123456789ABCDEF";
+
+         if (remaining < 4)
+           break;
+         * buf ++ = '<';
+         * buf ++ = hex[(c & 0xf0) >> 4];
+         * buf ++ = hex[c & 0x0f];
+         * buf ++ = '>';
+         remaining -= 4;
+       }
+
+      if (remaining == 0)
+       break;
+    }
+
+  * buf = 0;
+  return sec_name_buf;
+}
+
+static const char *
+printable_section_name_from_index (unsigned long ndx)
+{
+  if (ndx >= elf_header.e_shnum)
+    return _("<corrupt>");
+
+  return printable_section_name (section_headers + ndx);
+}
+
 /* Return a pointer to section NAME, or NULL if no such section exists.  */
 
 static Elf_Internal_Shdr *
@@ -1408,8 +1469,7 @@ dump_relocations (FILE * file,
                  if (ELF_ST_TYPE (psym->st_info) == STT_SECTION)
                    {
                      if (psym->st_shndx < elf_header.e_shnum)
-                       sec_name
-                         = SECTION_NAME (section_headers + psym->st_shndx);
+                       sec_name = SECTION_NAME (section_headers + psym->st_shndx);
                      else if (psym->st_shndx == SHN_ABS)
                        sec_name = "ABS";
                      else if (psym->st_shndx == SHN_COMMON)
@@ -4462,7 +4522,7 @@ process_program_headers (FILE * file)
            {
              if (!ELF_TBSS_SPECIAL (section, segment)
                  && ELF_SECTION_IN_SEGMENT_STRICT (section, segment))
-               printf ("%s ", SECTION_NAME (section));
+               printf ("%s ", printable_section_name (section));
            }
 
          putc ('\n',stdout);
@@ -4646,7 +4706,7 @@ get_32bit_elf_symbols (FILE * file,
   if (section->sh_size > current_file_size)
     {
       error (_("Section %s has an invalid sh_size of 0x%lx\n"),
-            SECTION_NAME (section), (unsigned long) section->sh_size);
+            printable_section_name (section), (unsigned long) section->sh_size);
       goto exit_point;
     }
 
@@ -4733,7 +4793,7 @@ get_64bit_elf_symbols (FILE * file,
   if (section->sh_size > current_file_size)
     {
       error (_("Section %s has an invalid sh_size of 0x%lx\n"),
-            SECTION_NAME (section), (unsigned long) section->sh_size);
+            printable_section_name (section), (unsigned long) section->sh_size);
       goto exit_point;
     }
 
@@ -5259,7 +5319,6 @@ process_section_headers (FILE * file)
              )
            request_dump_bynumber (i, DEBUG_DUMP);
        }
-
     }
 
   if (! do_sections)
@@ -5316,14 +5375,9 @@ process_section_headers (FILE * file)
     {
       printf ("  [%2u] ", i);
       if (do_section_details)
-       {
-         print_symbol (INT_MAX, SECTION_NAME (section));
-         printf ("\n      ");
-       }
+       printf ("%s\n      ", printable_section_name (section));
       else
-       {
-         print_symbol (-17, SECTION_NAME (section));
-       }
+       print_symbol (-17, SECTION_NAME (section));
 
       printf (do_wide ? " %-15s " : " %-15.15s ",
              get_section_type_name (section->sh_type));
@@ -5596,8 +5650,8 @@ process_section_groups (FILE * file)
     {
       if (section->sh_type == SHT_GROUP)
        {
-         char * name = SECTION_NAME (section);
-         char * group_name;
+         const char * name = printable_section_name (section);
+         const char * group_name;
          unsigned char * start;
          unsigned char * indices;
          unsigned int entry, j, size;
@@ -5741,7 +5795,7 @@ process_section_groups (FILE * file)
              if (do_section_groups)
                {
                  sec = section_headers + entry;
-                 printf ("   [%5u]   %s\n", entry, SECTION_NAME (sec));
+                 printf ("   [%5u]   %s\n", entry, printable_section_name (sec));
                }
 
              g = (struct group_list *) xmalloc (sizeof (struct group_list));
@@ -6049,7 +6103,7 @@ process_relocs (FILE * file)
              if (string_table == NULL)
                printf ("%d", section->sh_name);
              else
-               printf ("'%s'", SECTION_NAME (section));
+               printf ("'%s'", printable_section_name (section));
 
              printf (_(" at offset 0x%lx contains %lu entries:\n"),
                 rel_offset, (unsigned long) (rel_size / section->sh_entsize));
@@ -6466,7 +6520,7 @@ ia64_process_unwind (FILE * file)
          if (string_table == NULL)
            printf ("%d", unwsec->sh_name);
          else
-           printf (_("'%s'"), SECTION_NAME (unwsec));
+           printf ("'%s'", printable_section_name (unwsec));
        }
       else
        {
@@ -6481,7 +6535,7 @@ ia64_process_unwind (FILE * file)
          if (string_table == NULL)
            printf ("%d", unwsec->sh_name);
          else
-           printf (_("'%s'"), SECTION_NAME (unwsec));
+           printf ("'%s'", printable_section_name (unwsec));
 
          printf (_(" at offset 0x%lx contains %lu entries:\n"),
                  (unsigned long) unwsec->sh_offset,
@@ -6815,10 +6869,8 @@ hppa_process_unwind (FILE * file)
     {
       if (streq (SECTION_NAME (sec), ".PARISC.unwind"))
        {
-         printf (_("\nUnwind section "));
-         printf (_("'%s'"), SECTION_NAME (sec));
-
-         printf (_(" at offset 0x%lx contains %lu entries:\n"),
+         printf (_("\nUnwind section '%s' at offset 0x%lx contains %lu entries:\n"),
+                 printable_section_name (sec),
                  (unsigned long) sec->sh_offset,
                  (unsigned long) (sec->sh_size / (2 * eh_addr_size + 8)));
 
@@ -7011,6 +7063,10 @@ get_unwind_section_word (struct arm_unw_aux_info *  aux,
       if (rp->r_offset < word_offset)
        continue;
 
+      /* PR 17531: file: 027-161405-0.004  */
+      if (aux->symtab == NULL)
+       continue;
+
       sym = aux->symtab + ELF32_R_SYM (rp->r_info);
 
       if (arm_sec->rel_type == SHT_REL)
@@ -7022,7 +7078,11 @@ get_unwind_section_word (struct arm_unw_aux_info *  aux,
       else if (arm_sec->rel_type == SHT_RELA)
        offset = rp->r_addend;
       else
-       abort ();
+       {
+         error (_("Unknown section relocation type %d encountered\n"),
+                arm_sec->rel_type);
+         break;
+       }
 
       offset += sym->st_value;
       prelval = offset - (arm_sec->sec->sh_addr + rp->r_offset);
@@ -7057,12 +7117,16 @@ get_unwind_section_word (struct arm_unw_aux_info *  aux,
          prelval >>= 1;
        }
       else
-       /* This function currently only supports ARM and TI unwinders.  */
-       abort ();
+       {
+         /* This function currently only supports ARM and TI unwinders.  */
+         warn (_("Only TI and ARM unwinders are currently supported\n"));
+         break;
+       }
 
       word = (word & ~ (bfd_vma) 0x7fffffff) | (prelval & 0x7fffffff);
       addr->section = sym->st_shndx;
       addr->offset = offset;
+
       if (sym_name)
        * sym_name = sym->st_name;
       break;
@@ -7629,7 +7693,7 @@ decode_arm_unwind (struct arm_unw_aux_info *  aux,
       break;
 
     default:
-      error (_("Unsupported architecture type %d encountered when decoding unwind table"),
+      error (_("Unsupported architecture type %d encountered when decoding unwind table\n"),
             elf_header.e_machine);
     }
 
@@ -7749,7 +7813,7 @@ arm_process_unwind (FILE *file)
       break;
 
     default:
-      error (_("Unsupported architecture type %d encountered when processing unwind table"),
+      error (_("Unsupported architecture type %d encountered when processing unwind table\n"),
             elf_header.e_machine);
       return;
     }
@@ -7767,7 +7831,13 @@ arm_process_unwind (FILE *file)
          aux.symtab = GET_ELF_SYMBOLS (file, sec, & aux.nsyms);
 
          strsec = section_headers + sec->sh_link;
-         assert (aux.strtab == NULL);
+
+         /* PR binutils/17531 file: 011-12666-0.004.  */
+         if (aux.strtab != NULL)
+           {
+             warn (_("Multiple string tables found in file.\n"));
+             free (aux.strtab);
+           }
          aux.strtab = get_data (NULL, file, strsec->sh_offset,
                                 1, strsec->sh_size, _("string table"));
          aux.strtab_size = aux.strtab != NULL ? strsec->sh_size : 0;
@@ -7784,7 +7854,7 @@ arm_process_unwind (FILE *file)
        if (sec->sh_type == sec_type)
          {
            printf (_("\nUnwind table index '%s' at offset 0x%lx contains %lu entries:\n"),
-                   SECTION_NAME (sec),
+                   printable_section_name (sec),
                    (unsigned long) sec->sh_offset,
                    (unsigned long) (sec->sh_size / (2 * eh_addr_size)));
 
@@ -8868,17 +8938,15 @@ process_version_sections (FILE * file)
 
            found = 1;
 
-           printf
-             (_("\nVersion definition section '%s' contains %u entries:\n"),
-              SECTION_NAME (section), section->sh_info);
+           printf (_("\nVersion definition section '%s' contains %u entries:\n"),
+                   printable_section_name (section),
+                   section->sh_info);
 
            printf (_("  Addr: 0x"));
            printf_vma (section->sh_addr);
-           printf (_("  Offset: %#08lx  Link: %u (%s)\n"),
+           printf (_("  Offset: %#08lx  Link: %u (%s)"),
                    (unsigned long) section->sh_offset, section->sh_link,
-                   section->sh_link < elf_header.e_shnum
-                   ? SECTION_NAME (section_headers + section->sh_link)
-                   : _("<corrupt>"));
+                   printable_section_name_from_index (section->sh_link));
 
            edefs = (Elf_External_Verdef *)
                 get_data (NULL, file, section->sh_offset, 1,section->sh_size,
@@ -8986,15 +9054,13 @@ process_version_sections (FILE * file)
            found = 1;
 
            printf (_("\nVersion needs section '%s' contains %u entries:\n"),
-                   SECTION_NAME (section), section->sh_info);
+                   printable_section_name (section), section->sh_info);
 
            printf (_(" Addr: 0x"));
            printf_vma (section->sh_addr);
            printf (_("  Offset: %#08lx  Link: %u (%s)\n"),
                    (unsigned long) section->sh_offset, section->sh_link,
-                   section->sh_link < elf_header.e_shnum
-                   ? SECTION_NAME (section_headers + section->sh_link)
-                   : _("<corrupt>"));
+                   printable_section_name_from_index (section->sh_link));
 
            eneed = (Elf_External_Verneed *) get_data (NULL, file,
                                                        section->sh_offset, 1,
@@ -9134,13 +9200,13 @@ process_version_sections (FILE * file)
              }
 
            printf (_("\nVersion symbols section '%s' contains %d entries:\n"),
-                   SECTION_NAME (section), total);
+                   printable_section_name (section), total);
 
            printf (_(" Addr: "));
            printf_vma (section->sh_addr);
            printf (_("  Offset: %#08lx  Link: %u (%s)\n"),
                    (unsigned long) section->sh_offset, section->sh_link,
-                   SECTION_NAME (link_section));
+                   printable_section_name (link_section));
 
            off = offset_from_vma (file,
                                   version_info[DT_VERSIONTAGIDX (DT_VERSYM)],
@@ -9956,12 +10022,12 @@ process_symbol_table (FILE * file)
          if (section->sh_entsize == 0)
            {
              printf (_("\nSymbol table '%s' has a sh_entsize of zero!\n"),
-                     SECTION_NAME (section));
+                     printable_section_name (section));
              continue;
            }
 
          printf (_("\nSymbol table '%s' contains %lu entries:\n"),
-                 SECTION_NAME (section),
+                 printable_section_name (section),
                  (unsigned long) (section->sh_size / section->sh_entsize));
 
          if (is_32bit_elf)
@@ -11025,7 +11091,7 @@ apply_relocations (void * file,
          else
            {
              warn (_("unable to apply unsupported reloc type %d to section %s\n"),
-                   reloc_type, SECTION_NAME (section));
+                   reloc_type, printable_section_name (section));
              continue;
            }
 
@@ -11034,7 +11100,7 @@ apply_relocations (void * file,
            {
              warn (_("skipping invalid relocation offset 0x%lx in section %s\n"),
                    (unsigned long) rp->r_offset,
-                   SECTION_NAME (section));
+                   printable_section_name (section));
              continue;
            }
 
@@ -11042,7 +11108,7 @@ apply_relocations (void * file,
          if (sym_index >= num_syms)
            {
              warn (_("skipping invalid relocation symbol index 0x%lx in section %s\n"),
-                   sym_index, SECTION_NAME (section));
+                   sym_index, printable_section_name (section));
              continue;
            }
          sym = symtab + sym_index;
@@ -11066,7 +11132,7 @@ apply_relocations (void * file,
              warn (_("skipping unexpected symbol type %s in %ld'th relocation in section %s\n"),
                    get_symbol_type (ELF_ST_TYPE (sym->st_info)),
                    (long int)(rp - relocs),
-                   SECTION_NAME (relsec));
+                   printable_section_name (relsec));
              continue;
            }
 
@@ -11109,10 +11175,9 @@ apply_relocations (void * file,
 static int
 disassemble_section (Elf_Internal_Shdr * section, FILE * file)
 {
-  printf (_("\nAssembly dump of section %s\n"),
-         SECTION_NAME (section));
+  printf (_("\nAssembly dump of section %s\n"), printable_section_name (section));
 
-  /* XXX -- to be done --- XXX */
+  /* FIXME: XXX -- to be done --- XXX */
 
   return 1;
 }
@@ -11131,7 +11196,7 @@ get_section_contents (Elf_Internal_Shdr * section, FILE * file)
   if (num_bytes == 0 || section->sh_type == SHT_NOBITS)
     {
       printf (_("\nSection '%s' has no data to dump.\n"),
-             SECTION_NAME (section));
+             printable_section_name (section));
       return NULL;
     }
 
@@ -11148,14 +11213,13 @@ dump_section_as_strings (Elf_Internal_Shdr * section, FILE * file)
   char * data;
   char * end;
   char * start;
-  char * name = SECTION_NAME (section);
   bfd_boolean some_strings_shown;
 
   start = get_section_contents (section, file);
   if (start == NULL)
     return;
 
-  printf (_("\nString dump of section '%s':\n"), name);
+  printf (_("\nString dump of section '%s':\n"), printable_section_name (section));
 
   /* If the section being dumped has relocations against it the user might
      be expecting these relocations to have been applied.  Check for this
@@ -11226,7 +11290,7 @@ dump_section_as_bytes (Elf_Internal_Shdr * section,
   if (start == NULL)
     return;
 
-  printf (_("\nHex dump of section '%s':\n"), SECTION_NAME (section));
+  printf (_("\nHex dump of section '%s':\n"), printable_section_name (section));
 
   if (relocate)
     {
@@ -11457,6 +11521,7 @@ static int
 display_debug_section (int shndx, Elf_Internal_Shdr * section, FILE * file)
 {
   char * name = SECTION_NAME (section);
+  const char * print_name = printable_section_name (section);
   bfd_size_type length;
   int result = 1;
   int i;
@@ -11464,7 +11529,7 @@ display_debug_section (int shndx, Elf_Internal_Shdr * section, FILE * file)
   length = section->sh_size;
   if (length == 0)
     {
-      printf (_("\nSection '%s' has no debugging data.\n"), name);
+      printf (_("\nSection '%s' has no debugging data.\n"), print_name);
       return 0;
     }
   if (section->sh_type == SHT_NOBITS)
@@ -11473,7 +11538,8 @@ display_debug_section (int shndx, Elf_Internal_Shdr * section, FILE * file)
         which has the NOBITS type - the bits in the file will be random.
         This can happen when a file containing a .eh_frame section is
         stripped with the --only-keep-debug command line option.  */
-      printf (_("section '%s' has the NOBITS type - its contents are unreliable.\n"), name);
+      printf (_("section '%s' has the NOBITS type - its contents are unreliable.\n"),
+             print_name);
       return 0;
     }
 
@@ -11518,7 +11584,7 @@ display_debug_section (int shndx, Elf_Internal_Shdr * section, FILE * file)
 
   if (i == max)
     {
-      printf (_("Unrecognized debug section: %s\n"), name);
+      printf (_("Unrecognized debug section: %s\n"), print_name);
       result = 0;
     }
 
@@ -12625,7 +12691,13 @@ process_attributes (FILE * file,
                          (unsigned) section_len, (unsigned) len);
                  section_len = len;
                }
-
+             /* PR 17531: file: 001-101425-0.004  */
+             else if (section_len < 5)
+               {
+                 error (_("Attribute length of %u is too small\n"), (unsigned) section_len);
+                 break;
+               }
+             
              len -= section_len;
              section_len -= 4;
 
@@ -13198,7 +13270,7 @@ process_mips_specific (FILE * file)
            }
 
          printf (_("\nSection '%s' contains %d entries:\n"),
-                 SECTION_NAME (sect), cnt);
+                 printable_section_name (sect), cnt);
 
          option = iopt;
 
@@ -13438,8 +13510,17 @@ process_mips_specific (FILE * file)
       ent = pltgot;
       addr_size = (is_32bit_elf ? 4 : 8);
       local_end = pltgot + local_gotno * addr_size;
-      global_end = local_end + (symtabno - gotsym) * addr_size;
 
+      /* PR binutils/17533 file: 012-111227-0.004  */
+      if (symtabno < gotsym)
+       {
+         error (_("The GOT symbol offset (%lu) is greater than the symbol table size (%lu)\n"),
+                (long) gotsym, (long) symtabno);
+         return 0;
+       }
+      global_end = local_end + (symtabno - gotsym) * addr_size;
+      assert (global_end >= local_end);
       offset = offset_from_vma (file, pltgot, global_end - pltgot);
       data = (unsigned char *) get_data (NULL, file, offset,
                                          global_end - pltgot, 1,
@@ -13691,7 +13772,7 @@ process_gnu_liblist (FILE * file)
          strtab_size = string_sec->sh_size;
 
          printf (_("\nLibrary list section '%s' contains %lu entries:\n"),
-                 SECTION_NAME (section),
+                 printable_section_name (section),
                  (unsigned long) (section->sh_size / sizeof (Elf32_External_Lib)));
 
          puts (_("     Library              Time Stamp          Checksum   Version Flags"));