hammer: rgw: do not abort when accept a CORS request with short origin

[mattbenjamin]

http://tracker.ceph.com/issues/18213

[smithfarm]

original description

Fixed: #18187

when accept a CROS request, the request http origin shorter than the bucket's corsrule
(eg. origin: http://s.com corsrule: *.verylongdomain.com).
the rgw_cors.cc::is_string_in_set() will have a wrong index, the radosrgw server will
abort.

$ curl http://test.localhost:8000/app.data -H "Origin:http://s.com"

0> 2016-12-05 03:22:29.548138 7f6add05d700 -1 *** Caught signal (Aborted) **
in thread 7f6add05d700 thread_name:civetweb-worker

ceph version 11.0.2-2168-gd2f8fb4 (d2f8fb4)
1: (()+0x50720a) [0x7f6b147c420a]
2: (()+0xf370) [0x7f6b09a33370]
3: (gsignal()+0x37) [0x7f6b081ca1d7]
4: (abort()+0x148) [0x7f6b081cb8c8]
5: (__gnu_cxx::__verbose_terminate_handler()+0x165) [0x7f6b08ace9d5]
6: (()+0x5e946) [0x7f6b08acc946]
7: (()+0x5e973) [0x7f6b08acc973]
8: (()+0x5eb93) [0x7f6b08accb93]
9: (std::__throw_out_of_range(char const*)+0x77) 0x7f6b08b21a17]
10: (()+0xbd97a) [0x7f6b08b2b97a]
11: (()+0x449c1e) [0x7f6b14706c1e]
12: (RGWCORSRule::is_origin_present(char const*)+0x48) [0x7f6b147073b8]
13: (RGWCORSConfiguration::host_name_rule(char const*)+0x37) [0x7f6b147074e7]
14: (RGWOp::generate_cors_headers(std::string&, std::string&, std::string&, std::string&, unsigned int*)+0xa3) [0x7f6b14593e63]
15: (dump_access_control(req_state*, RGWOp*)+0x61) [0x7f6b14653f91]

Signed-off-by: LiuYang yippeetry@gmail.com
(cherry picked from commit 67d4d9e)

[smithfarm]

@mattbenjamin @oritwas @yehudasa This PR passed an rgw suite as detailed by http://tracker.ceph.com/issues/17151#note-30

Do you think it's OK to merge?

[smithfarm]

This passed another RGW suite at http://tracker.ceph.com/issues/17151#note-35

[oritwas]

lgtm