display_debug_pubnames_worker

	* dwarf.c (display_debug_pubnames_worker): Delete initial_length_size.
	Simplify length check.  Constrain reads to length given by header.

diff --git a/binutils/ChangeLog b/binutils/ChangeLog
index 5efa9305a6d383f8f211e21bfe96a70cadf39b09..5fd8bc1fa15ec3493b50a580a42ccbbf27c2413d 100644 (file)
--- a/binutils/ChangeLog
+++ b/binutils/ChangeLog
@@ -1,3 +1,8 @@
+2021-05-15  Alan Modra  <amodra@gmail.com>
+
+       * dwarf.c (display_debug_pubnames_worker): Delete initial_length_size.
+       Simplify length check.  Constrain reads to length given by header.
+
 2021-05-15  Alan Modra  <amodra@gmail.com>
 
        * dwarf.c (display_debug_lines_decoded): Don't use strnlen when

diff --git a/binutils/dwarf.c b/binutils/dwarf.c
index e881ceecb7953de08df76d8279a73d26e75c36f1..878f4f766dbe01d7e0215bd4d869ff374d4ddc9d 100644 (file)
--- a/binutils/dwarf.c
+++ b/binutils/dwarf.c
@@ -5616,29 +5616,23 @@ display_debug_pubnames_worker (struct dwarf_section *section,
   while (start < end)
     {
       unsigned char *data;
-      unsigned long sec_off;
-      unsigned int offset_size, initial_length_size;
+      unsigned long sec_off = start - section->start;
+      unsigned int offset_size;
 
       SAFE_BYTE_GET_AND_INC (names.pn_length, start, 4, end);
       if (names.pn_length == 0xffffffff)
        {
          SAFE_BYTE_GET_AND_INC (names.pn_length, start, 8, end);
          offset_size = 8;
-         initial_length_size = 12;
        }
       else
-       {
-         offset_size = 4;
-         initial_length_size = 4;
-       }
+       offset_size = 4;
 
-      sec_off = start - section->start;
-      if (sec_off + names.pn_length < sec_off
-         || sec_off + names.pn_length > section->size)
+      if (names.pn_length > (size_t) (end - start))
        {
          warn (_("Debug info is corrupted, %s header at %#lx has length %s\n"),
                section->name,
-               sec_off - initial_length_size,
+               sec_off,
                dwarf_vmatoa ("x", names.pn_length));
          break;
        }
@@ -5646,8 +5640,8 @@ display_debug_pubnames_worker (struct dwarf_section *section,
       data = start;
       start += names.pn_length;
 
-      SAFE_BYTE_GET_AND_INC (names.pn_version, data, 2, end);
-      SAFE_BYTE_GET_AND_INC (names.pn_offset, data, offset_size, end);
+      SAFE_BYTE_GET_AND_INC (names.pn_version, data, 2, start);
+      SAFE_BYTE_GET_AND_INC (names.pn_offset, data, offset_size, start);
 
       if (num_debug_info_entries != DEBUG_INFO_UNAVAILABLE
          && num_debug_info_entries > 0
@@ -5655,7 +5649,7 @@ display_debug_pubnames_worker (struct dwarf_section *section,
        warn (_(".debug_info offset of 0x%lx in %s section does not point to a CU header.\n"),
              (unsigned long) names.pn_offset, section->name);
 
-      SAFE_BYTE_GET_AND_INC (names.pn_size, data, offset_size, end);
+      SAFE_BYTE_GET_AND_INC (names.pn_size, data, offset_size, start);
 
       printf (_("  Length:                              %ld\n"),
              (long) names.pn_length);
@@ -5689,14 +5683,14 @@ display_debug_pubnames_worker (struct dwarf_section *section,
          bfd_size_type maxprint;
          dwarf_vma offset;
 
-         SAFE_BYTE_GET_AND_INC (offset, data, offset_size, end);
+         SAFE_BYTE_GET_AND_INC (offset, data, offset_size, start);
 
          if (offset == 0)
            break;
 
-         if (data >= end)
+         if (data >= start)
            break;
-         maxprint = (end - data) - 1;
+         maxprint = (start - data) - 1;
 
          if (is_gnu)
            {
@@ -5705,7 +5699,7 @@ display_debug_pubnames_worker (struct dwarf_section *section,
              const char *kind_name;
              int is_static;
 
-             SAFE_BYTE_GET_AND_INC (kind_data, data, 1, end);
+             SAFE_BYTE_GET_AND_INC (kind_data, data, 1, start);
              maxprint --;
              /* GCC computes the kind as the upper byte in the CU index
                 word, and then right shifts it by the CU index size.
@@ -5724,9 +5718,9 @@ display_debug_pubnames_worker (struct dwarf_section *section,
                    (unsigned long) offset, (int) maxprint, data);
 
          data += strnlen ((char *) data, maxprint);
-         if (data < end)
+         if (data < start)
            data++;
-         if (data >= end)
+         if (data >= start)
            break;
        }
     }