#if SANITIZER_FREEBSD
int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp,
const void *newp, uptr newlen) {
- static decltype(sysctlbyname) *real = nullptr;
- if (!real)
- real = (decltype(sysctlbyname) *)dlsym(RTLD_NEXT, "sysctlbyname");
- CHECK(real);
- return real(sname, oldp, (size_t *)oldlenp, newp, (size_t)newlen);
+ // Note: this function can be called during startup, so we need to avoid
+ // calling any interceptable functions. On FreeBSD >= 1300045 sysctlbyname()
+ // is a real syscall, but for older versions it calls sysctlnametomib()
+ // followed by sysctl(). To avoid calling the intercepted version and
+ // asserting if this happens during startup, call the real sysctlnametomib()
+ // followed by internal_sysctl() if the syscall is not available.
+#ifdef SYS___sysctlbyname
+ return internal_syscall(SYSCALL(__sysctlbyname), sname,
+ internal_strlen(sname), oldp, (size_t *)oldlenp, newp,
+ (size_t)newlen);
+#else
+ static decltype(sysctlnametomib) *real_sysctlnametomib = nullptr;
+ if (!real_sysctlnametomib)
+ real_sysctlnametomib =
+ (decltype(sysctlnametomib) *)dlsym(RTLD_NEXT, "sysctlnametomib");
+ CHECK(real_sysctlnametomib);
+
+ int oid[CTL_MAXNAME];
+ size_t len = CTL_MAXNAME;
+ if (real_sysctlnametomib(sname, oid, &len) == -1)
+ return (-1);
+ return internal_sysctl(oid, len, oldp, oldlenp, newp, newlen);
+#endif
}
#endif
#endif