Files
linux/tools/include/linux/poison.h
Arnaldo Carvalho de Melo 7aa534b8a3 tools include: Do not use poison with C++
[ Upstream commit 6ae8eefc6c ]

LIST_POISON[12] are used to initialize list_head and hlist_node
pointers, and do void pointer arithmetic, which C++ doesn't like, so, to
avoid drifting from the kernel by introducing some HLIST_POISON to do
away with void pointer math, just make those poisoned pointers be NULL
when building it with a C++ compiler.

Noticed with:

  $ make LLVM_CONFIG=/usr/bin/llvm-config-3.9 LIBCLANGLLVM=1
    CXX      util/c++/clang.o
    CXX	   util/c++/clang-test.o
  In file included from /home/lizj/linux/tools/include/linux/list.h:5:0,
                   from /home/lizj/linux/tools/perf/util/namespaces.h:13,
                   from /home/lizj/linux/tools/perf/util/util.h:15,
                   from /home/lizj/linux/tools/perf/util/util-cxx.h:20,
                   from util/c++/clang-c.h:5,
                   from util/c++/clang-test.cpp:2:
  /home/lizj/linux/tools/include/linux/list.h: In function ‘void list_del(list_head*)’:
  /home/lizj/linux/tools/include/linux/poison.h:14:31: error: pointer of type ‘void *’ used in arithmetic [-Werror=pointer-arith]
   # define POISON_POINTER_DELTA 0
                                 ^
  /home/lizj/linux/tools/include/linux/poison.h:22:41: note: in expansion of macro ‘POISON_POINTER_DELTA’
   #define LIST_POISON1  ((void *) 0x100 + POISON_POINTER_DELTA)
                                           ^
  /home/lizj/linux/tools/include/linux/list.h:107:16: note: in expansion of macro ‘LIST_POISON1’
    entry->next = LIST_POISON1;
                  ^
  In file included from /home/lizj/linux/tools/perf/util/namespaces.h:13:0,
                   from /home/lizj/linux/tools/perf/util/util.h:15,
                   from /home/lizj/linux/tools/perf/util/util-cxx.h:20,
                   from util/c++/clang-c.h:5,
                   from util/c++/clang-test.cpp:2:
  /home/lizj/linux/tools/include/linux/list.h:107:14: error: invalid conversion from ‘void*’ to ‘list_head*’ [-fpermissive]

Reported-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Philip Li <philip.li@intel.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-m5ei2o0mjshucbr28baf5lqz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09 22:01:49 +01:00

96 lines
2.6 KiB
C

#ifndef _LINUX_POISON_H
#define _LINUX_POISON_H
/********** include/linux/list.h **********/
/*
* Architectures might want to move the poison pointer offset
* into some well-recognized area such as 0xdead000000000000,
* that is also not mappable by user-space exploits:
*/
#ifdef CONFIG_ILLEGAL_POINTER_VALUE
# define POISON_POINTER_DELTA _AC(CONFIG_ILLEGAL_POINTER_VALUE, UL)
#else
# define POISON_POINTER_DELTA 0
#endif
#ifdef __cplusplus
#define LIST_POISON1 NULL
#define LIST_POISON2 NULL
#else
/*
* 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 *) 0x100 + POISON_POINTER_DELTA)
#define LIST_POISON2 ((void *) 0x200 + POISON_POINTER_DELTA)
#endif
/********** include/linux/timer.h **********/
/*
* Magic number "tsta" to indicate a static timer initializer
* for the object debugging code.
*/
#define TIMER_ENTRY_STATIC ((void *) 0x300 + POISON_POINTER_DELTA)
/********** mm/debug-pagealloc.c **********/
#ifdef CONFIG_PAGE_POISONING_ZERO
#define PAGE_POISON 0x00
#else
#define PAGE_POISON 0xaa
#endif
/********** mm/page_alloc.c ************/
#define TAIL_MAPPING ((void *) 0x400 + POISON_POINTER_DELTA)
/********** 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
/********** 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
#endif