PR25018, readelf crash on 32bits

Pointer comparisons after adding an offset just don't work to catch
overflow when the offset is a larger type than the pointer.

	PR 25018
	* dwarf.c (get_type_signedness): Delete ineffective pointer
	comparison check.  Properly range check uvalue offset on
	recursive call.
	(read_and_display_attr_value): Range check uvalue offset before
	calling get_type_signedness.
This commit is contained in:
Alan Modra 2019-09-23 08:53:07 +09:30
parent a13ba30840
commit b3fe587ed2
2 changed files with 13 additions and 4 deletions

View File

@ -1,3 +1,12 @@
2019-09-23 Alan Modra <amodra@gmail.com>
PR 25018
* dwarf.c (get_type_signedness): Delete ineffective pointer
comparison check. Properly range check uvalue offset on
recursive call.
(read_and_display_attr_value): Range check uvalue offset before
calling get_type_signedness.
2019-09-20 Alan Modra <amodra@gmail.com>
* ar.c (write_archive): Use bfd_set_thin_archive.

View File

@ -1999,9 +1999,6 @@ get_type_signedness (unsigned char * start,
* is_signed = FALSE;
if (data >= end)
return;
abbrev_number = read_uleb128 (data, & bytes_read, end);
data += bytes_read;
@ -2042,6 +2039,8 @@ get_type_signedness (unsigned char * start,
NB/ We need to avoid infinite recursion. */
return;
}
if (uvalue >= (size_t) (end - start))
return;
get_type_signedness (start, start + uvalue, end, pointer_size,
offset_size, dwarf_version, is_signed, TRUE);
break;
@ -2725,7 +2724,8 @@ read_and_display_attr_value (unsigned long attribute,
switch (attribute)
{
case DW_AT_type:
if (level >= 0 && level < MAX_CU_NESTING)
if (level >= 0 && level < MAX_CU_NESTING
&& uvalue < (size_t) (end - start))
{
bfd_boolean is_signed = FALSE;