[tor-bugs] #3135 [Tor Relay]: Saveconf request can terminate tor

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#3135: Saveconf request can terminate tor
-----------------------+----------------------------------------------------
 Reporter:  atagar     |          Owner:                    
     Type:  defect     |         Status:  new               
 Priority:  major      |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Relay  |        Version:  Tor: 0.2.3.1-alpha
 Keywords:             |         Parent:                    
   Points:             |   Actualpoints:                    
-----------------------+----------------------------------------------------

Comment(by atagar):

 Replying to [comment:1 arma]:
 > On step 2, does the user need to lack read permissions too?

 If the user has read permissions to the file then the torrc is
 successfully replaced (the user has write permissions for the directory in
 this case).

 > Can you set your ulimit -c to unlimited and give us the traceback from
 gdb?

 Here's the tracback:
 {{{
 ...
 May 11 18:52:00.000 [warn] Could not open "/home/atagar/.tor/torrc":
 Permission denied

 Program received signal SIGSEGV, Segmentation fault.
 0x003a123e in strncmp () from /lib/tls/i686/cmov/libc.so.6
 (gdb) backtrace
 #0  0x003a123e in strncmp () from /lib/tls/i686/cmov/libc.so.6
 #1  0x0811fbd5 in strcmpstart (s1=0x0,
     s2=0x8153fe4 "# This file was generated by Tor; if you edit it,
 comments will not be preserved") at util.c:504
 #2  0x080c36d3 in write_configuration_file () at config.c:4767
 #3  options_save_current () at config.c:4842
 #4  0x080dfa66 in handle_control_saveconf (conn=0x88957c8) at
 control.c:1182
 #5  connection_control_process_inbuf (conn=0x88957c8) at control.c:3001
 #6  0x080c60f5 in connection_process_inbuf (conn=0x0,
 package_partial=-16843009) at connection.c:3649
 #7  0x080ca9a2 in connection_handle_read_impl (conn=0x88957c8) at
 connection.c:2576
 #8  connection_handle_read (conn=0x88957c8) at connection.c:2616
 #9  0x08051934 in conn_read_callback (fd=19, event=2, _conn=0x88957c8) at
 main.c:665
 #10 0x0016f248 in event_base_loop () from /usr/lib/libevent-1.4.so.2
 #11 0x0804f639 in do_main_loop () at main.c:1784
 #12 0x0804f95d in tor_main (argc=3, argv=0xbffff4a4) at main.c:2457
 #13 0x0804ddeb in main (argc=3, argv=0xbffff4a4) at tor_main.c:30
 }}}

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3135#comment:3>
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