PR other/54411: integer overflow in objalloc_alloc

2012-09-18  Florian Weimer  <fweimer@redhat.com>

	PR other/54411
	* objalloc.h (objalloc_alloc): Do not use fast path on wraparound.

2012-09-18  Florian Weimer  <fweimer@redhat.com>

	PR other/54411
	* objalloc.c (_objalloc_alloc): Add overflow check covering
	alignment and CHUNK_HEADER_SIZE addition.

From-SVN: r191413
This commit is contained in:
Florian Weimer 2012-09-18 10:34:05 +02:00 committed by Florian Weimer
parent 4d3999876e
commit ed770de906
4 changed files with 22 additions and 4 deletions

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@ -1,3 +1,8 @@
2012-09-18 Florian Weimer <fweimer@redhat.com>
PR other/54411
* objalloc.h (objalloc_alloc): Do not use fast path on wraparound.
2012-09-06 Cary Coutant <ccoutant@google.com>
* dwarf2.def: Edit comment.

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@ -1,5 +1,5 @@
/* objalloc.h -- routines to allocate memory for objects
Copyright 1997, 2001 Free Software Foundation, Inc.
Copyright 1997-2012 Free Software Foundation, Inc.
Written by Ian Lance Taylor, Cygnus Solutions.
This program is free software; you can redistribute it and/or modify it
@ -91,7 +91,7 @@ extern void *_objalloc_alloc (struct objalloc *, unsigned long);
if (__len == 0) \
__len = 1; \
__len = (__len + OBJALLOC_ALIGN - 1) &~ (OBJALLOC_ALIGN - 1); \
(__len <= __o->current_space \
(__len != 0 && __len <= __o->current_space \
? (__o->current_ptr += __len, \
__o->current_space -= __len, \
(void *) (__o->current_ptr - __len)) \

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@ -1,3 +1,9 @@
2012-09-18 Florian Weimer <fweimer@redhat.com>
PR other/54411
* objalloc.c (_objalloc_alloc): Add overflow check covering
alignment and CHUNK_HEADER_SIZE addition.
2011-08-28 H.J. Lu <hongjiu.lu@intel.com>
* argv.c (dupargv): Replace malloc with xmalloc. Don't check

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@ -1,5 +1,5 @@
/* objalloc.c -- routines to allocate memory for objects
Copyright 1997 Free Software Foundation, Inc.
Copyright 1997-2012 Free Software Foundation, Inc.
Written by Ian Lance Taylor, Cygnus Solutions.
This program is free software; you can redistribute it and/or modify it
@ -112,8 +112,10 @@ objalloc_create (void)
/* Allocate space from an objalloc structure. */
PTR
_objalloc_alloc (struct objalloc *o, unsigned long len)
_objalloc_alloc (struct objalloc *o, unsigned long original_len)
{
unsigned long len = original_len;
/* We avoid confusion from zero sized objects by always allocating
at least 1 byte. */
if (len == 0)
@ -121,6 +123,11 @@ _objalloc_alloc (struct objalloc *o, unsigned long len)
len = (len + OBJALLOC_ALIGN - 1) &~ (OBJALLOC_ALIGN - 1);
/* Check for overflow in the alignment operation above and the
malloc argument below. */
if (len + CHUNK_HEADER_SIZE < original_len)
return NULL;
if (len <= o->current_space)
{
o->current_ptr += len;