diff options
| author | Ulrich Drepper <drepper@redhat.com> | 2005-12-18 06:58:22 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2005-12-18 06:58:22 +0000 |
| commit | 827b70873b41363c864fb65e99829204595d0f85 (patch) | |
| tree | 5d2e3811b6b0da44f18a7c8920dffdc524e3cd66 /elf | |
| parent | 8292f6fc71a60e92a23be053c500f504c6802c54 (diff) | |
| download | glibc-827b70873b41363c864fb65e99829204595d0f85.tar glibc-827b70873b41363c864fb65e99829204595d0f85.tar.gz glibc-827b70873b41363c864fb65e99829204595d0f85.tar.bz2 glibc-827b70873b41363c864fb65e99829204595d0f85.zip | |
* elf/Versions [GLIBC_PRIVATE]: Export __pointer_chk_guard if defined.
* elf/rtld.c: Define __pointer_chk_guard_local and if necessary
__pointer_chk_guard.
(_rtld_global_ro): Initialize _dl_pointer_guard.
(dl_main): Initialize __pointer_chk_guard_local and either
__pointer_chk_guard or TLS value if necessary.
(process_envvars): Recognize and handle LD_POINTER_GUARD.
* sysdeps/generic/ldsodefs.h (rtld_global_ro): Add _dl_pointer_guard.
* sysdeps/i386/__longjmp.S: Use PTR_DEMANGLE for PC if defined.
* sysdeps/x86_64/__longjmp.S: Likewise.
* sysdeps/i386/bsd-_setjmp.S: Use PTR_MANGLE for PC if defined.
* sysdeps/i386/bsd-_setjmp.S: Likewise.
* sysdeps/i386/setjmp.S: Likewise.
[IS_IN_rtld]: Avoid call to __sigjmp_save.
* sysdeps/i386/setjmp.S: Likewise.
* sysdeps/unix/sysv/linux/i386/sysdep.h: Define PTR_MANGLE and
PTR_DEMANGLE.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h: Likewise.
* sysdeps/i386/elf/setjmp.S: Removed.
* sysdeps/i386/elf/bsd-setjmp.S: Removed.
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/Versions | 2 | ||||
| -rw-r--r-- | elf/rtld.c | 32 |
2 files changed, 33 insertions, 1 deletions
diff --git a/elf/Versions b/elf/Versions index 9c53f1615e..87e27c5a7a 100644 --- a/elf/Versions +++ b/elf/Versions @@ -60,5 +60,7 @@ ld { _dl_make_stack_executable; # Only here for gdb while a better method is developed. _dl_debug_state; + # Pointer protection. + __pointer_chk_guard; } } diff --git a/elf/rtld.c b/elf/rtld.c index a89f89b3a5..9ef58bb328 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -90,6 +90,15 @@ INTDEF(_dl_argv) uintptr_t __stack_chk_guard attribute_relro; #endif +/* Only exported for architectures that don't store the pointer guard + value in thread local area. */ +uintptr_t __pointer_chk_guard_local + attribute_relro attribute_hidden __attribute__ ((nocommon)); +#ifndef THREAD_SET_POINTER_GUARD +strong_alias (__pointer_chk_guard_local, __pointer_chk_guard) +#endif + + /* List of auditing DSOs. */ static struct audit_list { @@ -142,6 +151,7 @@ struct rtld_global_ro _rtld_global_ro attribute_relro = ._dl_hwcap_mask = HWCAP_IMPORTANT, ._dl_lazy = 1, ._dl_fpu_control = _FPU_DEFAULT, + ._dl_pointer_guard = 1, /* Function pointers. */ ._dl_debug_printf = _dl_debug_printf, @@ -1823,6 +1833,20 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n", __stack_chk_guard = stack_chk_guard; #endif + /* Set up the pointer guard as well, if necessary. */ + if (GLRO(dl_pointer_guard)) + { + // XXX If it is cheap, we should use a separate value. + uintptr_t pointer_chk_guard; + hp_timing_t now; + HP_TIMING_NOW (now); + pointer_chk_guard = stack_chk_guard ^ now; +#ifdef THREAD_SET_POINTER_GUARD + THREAD_SET_POINTER_GUARD (pointer_chk_guard); +#endif + __pointer_chk_guard_local = pointer_chk_guard; + } + if (__builtin_expect (mode, normal) != normal) { /* We were run just to list the shared libraries. It is @@ -2575,7 +2599,13 @@ process_envvars (enum mode *modep) #endif if (!INTUSE(__libc_enable_secure) && memcmp (envline, "USE_LOAD_BIAS", 13) == 0) - GLRO(dl_use_load_bias) = envline[14] == '1' ? -1 : 0; + { + GLRO(dl_use_load_bias) = envline[14] == '1' ? -1 : 0; + break; + } + + if (memcmp (envline, "POINTER_GUARD", 13) == 0) + GLRO(dl_pointer_guard) = envline[14] == '0'; break; case 14: |