Fixed segfault with incorrect location nesting. A configuration with a named location inside a zero-length prefix or regex location used to trigger a segmentation fault, as ngx_http_core_location() failed to properly detect if a nested location was created. Example configuration to reproduce the problem: location "" { location @foo {} } Fix is to not rely on a parent location name length, but rather check command type we are currently parsing. Identical fix is also applied to ngx_http_rewrite_if(), which used to incorrectly assume the "if" directive is on server{} level in such locations. Reported by Markus Linnala. Found with afl-fuzz.