pef: sanity check before malloc
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Commit Message
And do the sanity check in a way that can't overflow.
* pef.c (bfd_pef_parse_function_stubs): Sanity check header
imported_library_count and total_imported_symbol_count before
allocating memory.
@@ -751,6 +751,13 @@ bfd_pef_parse_function_stubs (bfd *abfd,
if (ret < 0)
goto error;
+ if ((loaderlen - 56) / 24 < header.imported_library_count)
+ goto error;
+
+ if ((loaderlen - 56 - header.imported_library_count * 24) / 4
+ < header.total_imported_symbol_count)
+ goto error;
+
libraries = bfd_malloc
(header.imported_library_count * sizeof (bfd_pef_imported_library));
imports = bfd_malloc
@@ -758,8 +765,6 @@ bfd_pef_parse_function_stubs (bfd *abfd,
if (libraries == NULL || imports == NULL)
goto error;
- if (loaderlen < (56 + (header.imported_library_count * 24)))
- goto error;
for (i = 0; i < header.imported_library_count; i++)
{
ret = bfd_pef_parse_imported_library
@@ -768,9 +773,6 @@ bfd_pef_parse_function_stubs (bfd *abfd,
goto error;
}
- if (loaderlen < (56 + (header.imported_library_count * 24)
- + (header.total_imported_symbol_count * 4)))
- goto error;
for (i = 0; i < header.total_imported_symbol_count; i++)
{
ret = (bfd_pef_parse_imported_symbol