aha/include/linux/poison.h
David Rientjes 19da3dd157 flex_array: poison free elements
Newly initialized flex_array's and/or flex_array_part's are now poisoned
with a new poison value, FLEX_ARRAY_FREE.  It's value is similar to
POISON_FREE used in the various slab allocators, but is different to
distinguish between flex array's poisoned kmem and slab allocator poisoned
kmem.

This will allow us to identify flex_array_part's that only contain free
elements (and free them with an addition to the flex_array API).  This
could also be extended in the future to identify `get' uses on elements
that have not been `put'.

If __GFP_ZERO is passed for a part's gfp mask, the poisoning is avoided.
These elements are considered to be in-use since they have been
initialized.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:47 -07:00

77 lines
2.2 KiB
C

#ifndef _LINUX_POISON_H
#define _LINUX_POISON_H
/********** include/linux/list.h **********/
/*
* These are non-NULL pointers that will result in page faults
* under normal circumstances, used to verify that nobody uses
* non-initialized list entries.
*/
#define LIST_POISON1 ((void *) 0x00100100)
#define LIST_POISON2 ((void *) 0x00200200)
/********** include/linux/timer.h **********/
/*
* Magic number "tsta" to indicate a static timer initializer
* for the object debugging code.
*/
#define TIMER_ENTRY_STATIC ((void *) 0x74737461)
/********** mm/debug-pagealloc.c **********/
#define PAGE_POISON 0xaa
/********** mm/slab.c **********/
/*
* Magic nums for obj red zoning.
* Placed in the first word before and the first word after an obj.
*/
#define RED_INACTIVE 0x09F911029D74E35BULL /* when obj is inactive */
#define RED_ACTIVE 0xD84156C5635688C0ULL /* when obj is active */
#define SLUB_RED_INACTIVE 0xbb
#define SLUB_RED_ACTIVE 0xcc
/* ...and for poisoning */
#define POISON_INUSE 0x5a /* for use-uninitialised poisoning */
#define POISON_FREE 0x6b /* for use-after-free poisoning */
#define POISON_END 0xa5 /* end-byte of poisoning */
/********** arch/$ARCH/mm/init.c **********/
#define POISON_FREE_INITMEM 0xcc
/********** arch/ia64/hp/common/sba_iommu.c **********/
/*
* arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a
* value of "SBAIOMMU POISON\0" for spill-over poisoning.
*/
/********** fs/jbd/journal.c **********/
#define JBD_POISON_FREE 0x5b
#define JBD2_POISON_FREE 0x5c
/********** drivers/base/dmapool.c **********/
#define POOL_POISON_FREED 0xa7 /* !inuse */
#define POOL_POISON_ALLOCATED 0xa9 /* !initted */
/********** drivers/atm/ **********/
#define ATM_POISON_FREE 0x12
#define ATM_POISON 0xdeadbeef
/********** net/ **********/
#define NEIGHBOR_DEAD 0xdeadbeef
#define NETFILTER_LINK_POISON 0xdead57ac
/********** kernel/mutexes **********/
#define MUTEX_DEBUG_INIT 0x11
#define MUTEX_DEBUG_FREE 0x22
/********** lib/flex_array.c **********/
#define FLEX_ARRAY_FREE 0x6c /* for use-after-free poisoning */
/********** security/ **********/
#define KEY_DESTROY 0xbd
/********** sound/oss/ **********/
#define OSS_POISON_FREE 0xAB
#endif