* readelf.c (process_version_sections): Fix overflow checks to

avoid undefined behaviour.
This commit is contained in:
Nick Clifton 2013-01-29 08:55:09 +00:00
parent 29bd8b6b4e
commit 7e26601c54
2 changed files with 13 additions and 14 deletions

View File

@ -1,3 +1,8 @@
2013-01-29 Xi Wang <xi.wang@gmail.com>
* readelf.c (process_version_sections): Fix overflow checks to
avoid undefined behaviour.
2013-01-28 Doug Evans <dje@google.com>
* dwarf.c (display_gdb_index): Handle .gdb_index version 8.

View File

@ -1,7 +1,5 @@
/* readelf.c -- display contents of an ELF format file
Copyright 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
2008, 2009, 2010, 2011, 2012, 2013
Free Software Foundation, Inc.
Copyright 1998-2013 Free Software Foundation, Inc.
Originally developed by Eric Youngdale <eric@andante.jic.com>
Modifications by Nick Clifton <nickc@redhat.com>
@ -8469,8 +8467,8 @@ process_version_sections (FILE * file)
int j;
int isum;
/* Check for negative or very large indicies. */
if ((unsigned char *) edefs + idx < (unsigned char *) edefs)
/* Check for very large indicies. */
if (idx > (size_t) (endbuf - (char *) edefs))
break;
vstart = ((char *) edefs) + idx;
@ -8494,8 +8492,7 @@ process_version_sections (FILE * file)
ent.vd_ndx, ent.vd_cnt);
/* Check for overflow. */
if ((unsigned char *)(vstart + ent.vd_aux) < (unsigned char *) vstart
|| (unsigned char *)(vstart + ent.vd_aux) > (unsigned char *) endbuf)
if (ent.vd_aux > (size_t) (endbuf - vstart))
break;
vstart += ent.vd_aux;
@ -8515,8 +8512,7 @@ process_version_sections (FILE * file)
for (j = 1; j < ent.vd_cnt; j++)
{
/* Check for overflow. */
if ((unsigned char *)(vstart + aux.vda_next) < (unsigned char *) vstart
|| (unsigned char *)(vstart + aux.vda_next) > (unsigned char *) endbuf)
if (aux.vda_next > (size_t) (endbuf - vstart))
break;
isum += aux.vda_next;
@ -8586,7 +8582,7 @@ process_version_sections (FILE * file)
int isum;
char * vstart;
if ((unsigned char *) eneed + idx < (unsigned char *) eneed)
if (idx > (size_t) (endbuf - (char *) eneed))
break;
vstart = ((char *) eneed) + idx;
@ -8611,8 +8607,7 @@ process_version_sections (FILE * file)
printf (_(" Cnt: %d\n"), ent.vn_cnt);
/* Check for overflow. */
if ((unsigned char *)(vstart + ent.vn_aux) < (unsigned char *) vstart
|| (unsigned char *)(vstart + ent.vn_aux) > (unsigned char *) endbuf)
if (ent.vn_aux > (size_t) (endbuf - vstart))
break;
vstart += ent.vn_aux;
@ -8643,8 +8638,7 @@ process_version_sections (FILE * file)
get_ver_flags (aux.vna_flags), aux.vna_other);
/* Check for overflow. */
if ((unsigned char *)(vstart + aux.vna_next) < (unsigned char *) vstart
|| (unsigned char *)(vstart + aux.vna_next) > (unsigned char *) endbuf)
if (aux.vna_next > (size_t) (endbuf - vstart))
break;
isum += aux.vna_next;