Don't use broken DL_AUTO_FUNCTION_ADDRESS()

On hppa and ia64, the macro DL_AUTO_FUNCTION_ADDRESS() uses the
variable fptr[2] in it's own scope.

The content of fptr[] is thus undefined right after the macro exits.
Newer gcc's (>= 4.7) reuse the stack space of this variable triggering
a segmentation fault in dl-init.c:69.

To fix this we rewrite the macros to make the call directly to init
and fini without needing to pass back a constructed function pointer.
This commit is contained in:
Guy Martin 2013-11-21 13:23:16 -05:00 committed by Carlos O'Donell
parent d33cafadfe
commit daf75146de
11 changed files with 94 additions and 57 deletions

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@ -1,3 +1,12 @@
2013-11-21 Guy Martin <gmsoft@tuxicoman.be>
* sysdeps/generic/ldsodefs.h: Replace DL_DT_INIT_ADDRESS() and
DL_DT_FINI_ADDRESS() macro with DL_CALL_DT_INIT() and
DL_CALL_DT_FINI() that call the functions directly.
* elf/dl-init.c: Use the new DL_CALL_DT_INIT() macro.
* elf/dl-close.c: Use the new DL_CALL_DT_FINI() macro.
* elf/dl-fini.c: Likewise.
2013-11-20 Ondřej Bílka <neleai@seznam.cz>
* malloc/hooks.c (memalign_check): Add alignment rounding.

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@ -274,9 +274,8 @@ _dl_close_worker (struct link_map *map)
/* Next try the old-style destructor. */
if (imap->l_info[DT_FINI] != NULL)
(*(void (*) (void)) DL_DT_FINI_ADDRESS
(imap, ((void *) imap->l_addr
+ imap->l_info[DT_FINI]->d_un.d_ptr))) ();
DL_CALL_DT_FINI (imap, ((void *) imap->l_addr
+ imap->l_info[DT_FINI]->d_un.d_ptr));
}
#ifdef SHARED

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@ -254,7 +254,7 @@ _dl_fini (void)
/* Next try the old-style destructor. */
if (l->l_info[DT_FINI] != NULL)
((fini_t) DL_DT_FINI_ADDRESS (l, l->l_addr + l->l_info[DT_FINI]->d_un.d_ptr)) ();
DL_CALL_DT_FINI(l, l->l_addr + l->l_info[DT_FINI]->d_un.d_ptr);
}
#ifdef SHARED

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@ -61,13 +61,7 @@ call_init (struct link_map *l, int argc, char **argv, char **env)
- the others in the DT_INIT_ARRAY.
*/
if (l->l_info[DT_INIT] != NULL)
{
init_t init = (init_t) DL_DT_INIT_ADDRESS
(l, l->l_addr + l->l_info[DT_INIT]->d_un.d_ptr);
/* Call the function. */
init (argc, argv, env);
}
DL_CALL_DT_INIT(l, l->l_addr + l->l_info[DT_INIT]->d_un.d_ptr, argc, argv, env);
/* Next see whether there is an array with initialization functions. */
ElfW(Dyn) *init_array = l->l_info[DT_INIT_ARRAY];

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@ -1,3 +1,12 @@
2013-11-21 Guy Martin <gmsoft@tuxicoman.be>
* sysdeps/hppa/dl-lookupcfg.h: Remove obsolete
DL_DT_INIT_ADDRESS() and DL_DT_FINI_ADDRESS() macro and implement
DL_CALL_DT_INIT() as well as DL_CALL_DT_FINI().
Define DL_DT_FUNCTION_ADDRESS().
* sysdeps/hppa/dl-machine.h: Update ELF_MACHINE_START_ADDRESS()
to use DL_DT_FUNCTION_ADDRESS().
2013-10-30 Mike Frysinger <vapier@gentoo.org>
* sysdeps/hppa/configure.in: Moved to ...

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@ -1,3 +1,12 @@
2013-11-21 Guy Martin <gmsoft@tuxicoman.be>
* sysdeps/ia64/dl-lookupcfg.h: Remove obsolete
DL_DT_INIT_ADDRESS() and DL_DT_FINI_ADDRESS() macro and implement
DL_CALL_DT_INIT() as well as DL_CALL_DT_FINI().
Define DL_DT_FUNCTION_ADDRESS().
* sysdeps/ia64/dl-machine.h: Update ELF_MACHINE_START_ADDRESS()
to use DL_DT_FUNCTION_ADDRESS().
2013-10-30 Mike Frysinger <vapier@gentoo.org>
* sysdeps/ia64/configure.in: Moved to ...

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@ -38,32 +38,36 @@ void _dl_unmap (struct link_map *map);
#define DL_UNMAP(map) _dl_unmap (map)
#define DL_AUTO_FUNCTION_ADDRESS(map, addr) \
({ \
unsigned int fptr[2]; \
fptr[0] = (unsigned int) (addr); \
fptr[1] = (map)->l_info[DT_PLTGOT]->d_un.d_ptr; \
/* Set bit 30 to indicate to $$dyncall that this is a PLABEL. */ \
(ElfW(Addr))((unsigned int)fptr | 2); \
})
#define DL_DT_FUNCTION_ADDRESS(map, start, attr, addr) \
attr volatile unsigned int fptr[2]; \
/* The test for "start & 2" below is to accommodate old binaries which \
violated the ELF ABI by pointing DT_INIT and DT_FINI at a function \
descriptor. */ \
if ((ElfW(Addr)) (start) & 2) \
addr = (ElfW(Addr)) start; \
else \
{ \
fptr[0] = (unsigned int) (start); \
fptr[1] = (map)->l_info[DT_PLTGOT]->d_un.d_ptr; \
/* Set bit 30 to indicate to $$dyncall that this is a PLABEL. */ \
addr = (ElfW(Addr))((unsigned int)fptr | 2); \
} \
#define DL_STATIC_FUNCTION_ADDRESS(map, addr) \
({ \
static unsigned int fptr[2]; \
fptr[0] = (unsigned int) (addr); \
fptr[1] = (map)->l_info[DT_PLTGOT]->d_un.d_ptr; \
/* Set bit 30 to indicate to $$dyncall that this is a PLABEL. */ \
(ElfW(Addr))((unsigned int)fptr | 2); \
})
#define DL_CALL_DT_INIT(map, start, argc, argv, env) \
{ \
ElfW(Addr) addr; \
DL_DT_FUNCTION_ADDRESS(map, start, , addr) \
init_t init = (init_t) addr; \
init (argc, argv, env); \
}
/* The test for "addr & 2" below is to accommodate old binaries which
violated the ELF ABI by pointing DT_INIT and DT_FINI at a function
descriptor. */
#define DL_DT_INIT_ADDRESS(map, addr) \
((Elf32_Addr)(addr) & 2 ? (addr) : DL_AUTO_FUNCTION_ADDRESS (map, addr))
#define DL_DT_FINI_ADDRESS(map, addr) \
((Elf32_Addr)(addr) & 2 ? (addr) : DL_AUTO_FUNCTION_ADDRESS (map, addr))
#define DL_CALL_DT_FINI(map, start) \
{ \
ElfW(Addr) addr; \
DL_DT_FUNCTION_ADDRESS(map, start, , addr) \
fini_t fini = (fini_t) addr; \
fini (); \
}
/* The type of the return value of fixup/profile_fixup */
#define DL_FIXUP_VALUE_TYPE struct fdesc

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@ -490,8 +490,12 @@ asm ( \
#define ELF_MACHINE_NO_REL 1
/* Return the address of the entry point. */
#define ELF_MACHINE_START_ADDRESS(map, start) \
DL_STATIC_FUNCTION_ADDRESS (map, start)
#define ELF_MACHINE_START_ADDRESS(map, start) \
({ \
ElfW(Addr) addr; \
DL_DT_FUNCTION_ADDRESS(map, start, static, addr) \
addr; \
})
/* We define an initialization functions. This is called very early in
* _dl_sysdep_start. */

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@ -39,24 +39,28 @@ extern void _dl_unmap (struct link_map *map);
#define DL_UNMAP(map) _dl_unmap (map)
#define DL_AUTO_FUNCTION_ADDRESS(map, addr) \
({ \
unsigned long int fptr[2]; \
fptr[0] = (unsigned long int) (addr); \
fptr[1] = (map)->l_info[DT_PLTGOT]->d_un.d_ptr; \
(Elf64_Addr) fptr; \
})
#define DL_DT_FUNCTION_ADDRESS(map, start, attr, addr) \
attr volatile unsigned long int fptr[2]; \
fptr[0] = (unsigned long int) (start); \
fptr[1] = (map)->l_info[DT_PLTGOT]->d_un.d_ptr; \
addr = (ElfW(Addr)) fptr; \
#define DL_STATIC_FUNCTION_ADDRESS(map, addr) \
({ \
static unsigned long int fptr[2]; \
fptr[0] = (unsigned long int) (addr); \
fptr[1] = (map)->l_info[DT_PLTGOT]->d_un.d_ptr; \
(Elf64_Addr) fptr; \
})
#define DL_CALL_DT_INIT(map, start, argc, argv, env) \
{ \
ElfW(Addr) addr; \
DL_DT_FUNCTION_ADDRESS(map, start, , addr) \
init_t init = (init_t) addr; \
init (argc, argv, env); \
}
#define DL_CALL_DT_FINI(map, start) \
{ \
ElfW(Addr) addr; \
DL_DT_FUNCTION_ADDRESS(map, start, , addr) \
fini_t fini = (fini_t) addr; \
fini (); \
}
#define DL_DT_INIT_ADDRESS(map, addr) DL_AUTO_FUNCTION_ADDRESS (map, addr)
#define DL_DT_FINI_ADDRESS(map, addr) DL_AUTO_FUNCTION_ADDRESS (map, addr)
/* The type of the return value of fixup/profile_fixup. */
#define DL_FIXUP_VALUE_TYPE struct fdesc
/* Construct a value of type DL_FIXUP_VALUE_TYPE from a code address

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@ -322,8 +322,12 @@ elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
#define ELF_MACHINE_NO_REL 1
/* Return the address of the entry point. */
#define ELF_MACHINE_START_ADDRESS(map, start) \
DL_STATIC_FUNCTION_ADDRESS (map, start)
#define ELF_MACHINE_START_ADDRESS(map, start) \
({ \
ElfW(Addr) addr; \
DL_DT_FUNCTION_ADDRESS(map, start, static, addr) \
addr; \
})
/* Fixup a PLT entry to bounce directly to the function at VALUE. */
static inline struct fdesc __attribute__ ((always_inline))

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@ -76,8 +76,9 @@ typedef struct link_map *lookup_t;
# define DL_SYMBOL_ADDRESS(map, ref) \
(void *) (LOOKUP_VALUE_ADDRESS (map) + ref->st_value)
# define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
# define DL_DT_INIT_ADDRESS(map, start) (start)
# define DL_DT_FINI_ADDRESS(map, start) (start)
# define DL_CALL_DT_INIT(map, start, argc, argv, env) \
((init_t) (start)) (argc, argv, env)
# define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
#endif
/* On some architectures dladdr can't use st_size of all symbols this way. */