[tor-bugs] #7743 [Tor]: Avoid needless wasted space in cells

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#7743: Avoid needless wasted space in cells
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    Reporter:  nickm     |       Owner:  nickm                                  
        Type:  defect    |      Status:  reopened                               
    Priority:  critical  |   Milestone:  Tor: 0.2.4.x-final                     
   Component:  Tor       |     Version:                                         
  Resolution:            |    Keywords:  backport-023 tor-relay regression bwbug
      Parent:            |      Points:                                         
Actualpoints:            |  
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Comment(by andrea):

 Stack dump for SIGSEGV seen while testing:

 #0  0x0000000000539321 in tor_strlower (s=0x0) at src/common/util.c:517
 #1  0x00000000004d56c4 in connection_exit_begin_conn (cell=0x7fffffffde30,
 circ=0x1bec960)
     at src/or/connection_edge.c:2482
 #2  0x0000000000429143 in connection_edge_process_relay_cell
 (cell=0x7fffffffde30, circ=0x1bec960, conn=0x0,
     layer_hint=0x0) at src/or/relay.c:1190
 #3  0x0000000000425e66 in circuit_receive_relay_cell (cell=0x7fffffffde30,
 circ=0x1bec960,
     cell_direction=CELL_DIRECTION_OUT) at src/or/relay.c:193
 #4  0x00000000004b00a9 in command_process_relay_cell (cell=0x7fffffffde30,
 chan=0x1d9c0e0) at src/or/command.c:407
 #5  0x00000000004af32d in command_process_cell (chan=0x1d9c0e0,
 cell=0x7fffffffde30) at src/or/command.c:147
 #6  0x0000000000485fac in channel_queue_cell (chan=0x1d9c0e0,
 cell=0x7fffffffde30) at src/or/channel.c:2516
 #7  0x000000000048cb48 in channel_tls_handle_cell (cell=0x7fffffffde30,
 conn=0x22fc5e0) at src/or/channeltls.c:921
 #8  0x00000000004db608 in connection_or_process_cells_from_inbuf
 (conn=0x22fc5e0) at src/or/connection_or.c:1937
 #9  0x00000000004d80a6 in connection_or_process_inbuf (conn=0x22fc5e0) at
 src/or/connection_or.c:461
 #10 0x00000000004cbba9 in connection_process_inbuf (conn=0x22fc5e0,
 package_partial=1) at src/or/connection.c:3954
 #11 0x00000000004c95c9 in connection_handle_read_impl (conn=0x22fc5e0) at
 src/or/connection.c:2819
 #12 0x00000000004c96f4 in connection_handle_read (conn=0x22fc5e0) at
 src/or/connection.c:2860
 #13 0x000000000040a26f in conn_read_callback (fd=22, event=2,
 _conn=0x22fc5e0) at src/or/main.c:722
 #14 0x00007ffff772f930 in event_process_active (base=0x7e4c70,
 flags=<value optimized out>) at event.c:395
 #15 event_base_loop (base=0x7e4c70, flags=<value optimized out>) at
 event.c:547
 #16 0x000000000040cc77 in do_main_loop () at src/or/main.c:1989
 #17 0x000000000040e237 in tor_main (argc=3, argv=0x7fffffffe658) at
 src/or/main.c:2701
 #18 0x0000000000408844 in main (argc=3, argv=0x7fffffffe658) at
 src/or/tor_main.c:30

 Not sure if this is related to this patch or not yet.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7743#comment:16>
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