diff options
author | Kyle Evans <kevans@FreeBSD.org> | 2019-11-25 03:49:38 +0000 |
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committer | Kyle Evans <kevans@FreeBSD.org> | 2019-11-25 03:49:38 +0000 |
commit | bf6ee21ac9b83c8e679c549932d0065739cbc17c (patch) | |
tree | 322419ec27ac9f90339eb4b81fbed2cde16f3214 | |
parent | 62b436d466744fb6a09330878e077b614df67270 (diff) |
Notes
-rw-r--r-- | lib/libc/secure/stack_protector.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/lib/libc/secure/stack_protector.c b/lib/libc/secure/stack_protector.c index 34bb7d0332a3b..63c02cd960338 100644 --- a/lib/libc/secure/stack_protector.c +++ b/lib/libc/secure/stack_protector.c @@ -40,11 +40,29 @@ __FBSDID("$FreeBSD$"); #include <unistd.h> #include "libc_private.h" +/* + * We give __guard_setup a defined priority early on so that statically linked + * applications have a defined priority at which __stack_chk_guard will be + * getting initialized. This will not matter to most applications, because + * they're either not usually statically linked or they simply don't do things + * in constructors that would be adversely affected by their positioning with + * respect to this initialization. + * + * This conditional should be removed when GCC 4.2 is removed. + */ +#if __has_attribute(__constructor__) || __GNUC_PREREQ__(4, 3) +#define _GUARD_SETUP_CTOR_ATTR \ + __attribute__((__constructor__ (200), __used__)); +#else +#define _GUARD_SETUP_CTOR_ATTR \ + __attribute__((__constructor__, __used__)); +#endif + extern int __sysctl(const int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen); long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0}; -static void __guard_setup(void) __attribute__((__constructor__, __used__)); +static void __guard_setup(void) _GUARD_SETUP_CTOR_ATTR; static void __fail(const char *); void __stack_chk_fail(void); void __chk_fail(void); |