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| author | Florian Weimer <fweimer@redhat.com> | 2015-10-15 09:23:07 +0200 |
|---|---|---|
| committer | Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com> | 2015-12-30 11:57:28 -0200 |
| commit | 80e44fad705561e39d8001c8258a8bae9c149fc7 (patch) | |
| tree | e5680ef540ec986c87aede19bce46642baed45a7 | |
| parent | d4deb63367247eaddcbe10b872d39ff70659eaf4 (diff) | |
| download | glibc-80e44fad705561e39d8001c8258a8bae9c149fc7.tar.gz | |
Always enable pointer guard [BZ #18928]
Honoring the LD_POINTER_GUARD environment variable in AT_SECURE mode
has security implications. This commit enables pointer guard
unconditionally, and the environment variable is now ignored.
[BZ #18928]
* sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove
_dl_pointer_guard member.
* elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard
initializer.
(security_init): Always set up pointer guard.
(process_envvars): Do not process LD_POINTER_GUARD.
(cherry picked from commit a014cecd82b71b70a6a843e250e06b541ad524f7)
Conflicts:
NEWS
| -rw-r--r-- | ChangeLog | 10 | ||||
| -rw-r--r-- | NEWS | 5 | ||||
| -rw-r--r-- | elf/rtld.c | 15 | ||||
| -rw-r--r-- | sysdeps/generic/ldsodefs.h | 3 |
4 files changed, 18 insertions, 15 deletions
@@ -1,3 +1,13 @@ +2015-12-30 Florian Weimer <fweimer@redhat.com> + + [BZ #18928] + * sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove + _dl_pointer_guard member. + * elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard + initializer. + (security_init): Always set up pointer guard. + (process_envvars): Do not process LD_POINTER_GUARD. + 2014-06-03 Guo Yixuan <culu.gyx@gmail.com> [BZ #16882] @@ -10,7 +10,10 @@ Version 2.18.1 * The following bugs are resolved with this release: 15073, 15128, 15909, 15996, 16150, 16169, 16387, 16510, 16885, 16916, - 16943, 16958. + 16943, 16958, 18928. + +* The LD_POINTER_GUARD environment variable can no longer be used to + disable the pointer guard feature. It is always enabled. Version 2.18 diff --git a/elf/rtld.c b/elf/rtld.c index 91da88cdd1..b2fce266fb 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -162,7 +162,6 @@ 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, ._dl_pagesize = EXEC_PAGESIZE, ._dl_inhibit_cache = 0, @@ -857,15 +856,12 @@ security_init (void) #endif /* Set up the pointer guard as well, if necessary. */ - if (GLRO(dl_pointer_guard)) - { - uintptr_t pointer_chk_guard = _dl_setup_pointer_guard (_dl_random, - stack_chk_guard); + uintptr_t pointer_chk_guard + = _dl_setup_pointer_guard (_dl_random, stack_chk_guard); #ifdef THREAD_SET_POINTER_GUARD - THREAD_SET_POINTER_GUARD (pointer_chk_guard); + THREAD_SET_POINTER_GUARD (pointer_chk_guard); #endif - __pointer_chk_guard_local = pointer_chk_guard; - } + __pointer_chk_guard_local = pointer_chk_guard; /* We do not need the _dl_random value anymore. The less information we leave behind, the better, so clear the @@ -2606,9 +2602,6 @@ process_envvars (enum mode *modep) 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: diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index e7b0516aaf..6ccbd7138e 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -589,9 +589,6 @@ struct rtld_global_ro /* List of auditing interfaces. */ struct audit_ifaces *_dl_audit; unsigned int _dl_naudit; - - /* 0 if internal pointer values should not be guarded, 1 if they should. */ - EXTERN int _dl_pointer_guard; }; # define __rtld_global_attribute__ # ifdef IS_IN_rtld |