WMS request causes AGG segfault

[lagerratrobe]

• WMS request generated by TileCache is causing MapServer to segfault. Request looks like this:

​http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/clip_test/shape_seattle.map&layers=roadsPG&styles=&service=WMS&width=256&format=image/png&request=GetMap&height=256&srs=EPSG:4326&version=1.1.1&bbox=-122.338256836,47.6586914062,-122.332763672,47.6641845703

• Area of request can successfully be rendered using "MODE=MAP":

​http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/clip_test/shape_seattle.map&mode=map

• gdb output of WMS request below:

  $ gdb /usr/lib/cgi-bin/mapserv
  GNU gdb (GDB) 7.0-ubuntu
  Copyright (C) 2009 Free Software Foundation, Inc.
  License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
  This is free software: you are free to change and redistribute it.
  There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
  and "show warranty" for details.
  This GDB was configured as "i486-linux-gnu".
  For bug reporting instructions, please see:
  <http://www.gnu.org/software/gdb/bugs/>...
  Reading symbols from /usr/lib/cgi-bin/mapserv...done.
  (gdb) run "QUERY_STRING=map=/var/www/mapfiles/clip_test/shape_seattle.map&layers=roadsPG&styles=&service=WMS&width=256&format=image/png&request=GetMap&height=256&srs=EPSG:4326&version=1.1.1&bbox=-122.338256836,47.6586914062,-122.332763672,47.6641845703"
  Starting program: /usr/lib/cgi-bin/mapserv "QUERY_STRING=map=/var/www/mapfiles/clip_test/shape_seattle.map&layers=roadsPG&styles=&service=WMS&width=256&format=image/png&request=GetMap&height=256&srs=EPSG:4326&version=1.1.1&bbox=-122.338256836,47.6586914062,-122.332763672,47.6641845703"
  [Thread debugging using libthread_db enabled]
  
  Program received signal SIGSEGV, Segmentation fault.
  0x00d91bf2 in ?? () from /lib/tls/i686/cmov/libc.so.6
  (gdb) bt
  #0  0x00d91bf2 in ?? () from /lib/tls/i686/cmov/libc.so.6
  #1  0x00d93868 in malloc () from /lib/tls/i686/cmov/libc.so.6
  #2  0x007a9bb7 in operator new(unsigned int) () from /usr/lib/libstdc++.so.6
  #3  0x007a9ced in operator new[](unsigned int) () from /usr/lib/libstdc++.so.6
  #4  0x080dbdd5 in void mapserver::render_scanlines<mapserver::rasterizer_scanline_aa<mapserver::rasterizer_sl_clip<mapserver::ras_conv_int> >, mapserver::scanline_u8, mapserver::renderer_scanline_aa_solid<mapserver::renderer_base<mapserver::pixfmt_alpha_blend_rgba<mapserver::blender_rgba_pre<mapserver::rgba8, mapserver::order_bgra>, mapserv_row_ptr_cache<int>, int> > > >(mapserver::rasterizer_scanline_aa<mapserver::rasterizer_sl_clip<mapserver::ras_conv_int> >&, mapserver::scanline_u8&, mapserver::renderer_scanline_aa_solid<mapserver::renderer_base<mapserver::pixfmt_alpha_blend_rgba<mapserver::blender_rgba_pre<mapserver::rgba8, mapserver::order_bgra>, mapserv_row_ptr_cache<int>, int> > >&) ()
  #5  0x080ba7ac in T.1744 ()
  #6  0x080bdbda in msDrawShadeSymbolAGG ()
  #7  0x0813b3d2 in msDrawShadeSymbol ()
  #8  0x0809ff17 in msDrawShape ()
  #9  0x080a2cfe in msDrawVectorLayer ()
  #10 0x080a343d in msDrawLayer ()
  #11 0x080a4fd7 in msDrawMap ()
  #12 0x08157d82 in msWMSGetMap ()
  #13 0x0815cf36 in msWMSDispatch ()
  #14 0x080e9924 in msOWSDispatch ()
  #15 0x08056583 in main ()
  (gdb) 
  

[lagerratrobe]

mapfile and data to replicate error

[tbonfort]

I can't reproduce the segfault.

Can you reproduce the segfault using the exact data and mapfile form the tarball included in the ticket?

It seems very awkward that the segfault is happening fro you in the shade (polygon) symbol renderer, whereas the layer you are calling is a line symbol.