Crash when reading the included elephant.ply model.

[Rene Lindsay]

The "file.read(memory_stream);" function causes a segfault, when loading the included elephant.ply file, from the assets folder.
The other .ply files all load ok.

(Ubuntu 18.04)

[karamellpelle]

And here is something similar (commit 37bbe91, MacOS High Sierra, clang):

Having the following main() in example.cpp:

int main(int argc, char *argv[])
{
    if (argc < 2) return 1;

    read_ply_file( argv[1], true );
    return EXIT_SUCCESS;
}

and removing the size_hint argument 3 at line 198:

    //try { faces = file.request_properties_from_element("face", { "vertex_indices" }, 3); }
    try { faces = file.request_properties_from_element("face", { "vertex_indices" }); }

the program segfault on the assets bunny.ply, elephant.ply, icosahedron_ascii.ply, sofa_ascii.ply, but does not segfault on icosahedron.ply, sofa.ply. So it does not segfault on the binary models except elephant.ply which segfaults anyway: even with a size_hint of 3.

It is difficult to debug, but sometimes I've got the message (in another application, but similar code)

App_ExampleBrowser(918,0x7fff9fe19380) malloc: *** error for object 0x100da4ae8: incorrect checksum for freed object - object was probably modified after being freed.
*** set a breakpoint in malloc_error_break to debug

[Dimitri Diakopoulos]

Looking at this @rjklindsay + @karamellpelle. I can replicate the crash on elephant.ply but not on any other included assets. @karamellpelle can you confirm that elephant is the only affected model?

[Dimitri Diakopoulos]

This should be fixed on master!