Added missing 8 bytes to compressed binary pcd length.

[floriankramer]

When compressed binary pcd files are read the size passed to mmap for memory mapping the file is 8 bytes to small, as the size of the two four byte unsigned integers used to store the uncompressed and compressed size of the data in the pcd file are not added to the total size. This can lead to a segfault, when the size of a pcd file is at most 8 bytes smaller than the next multiple of the page size of the virtual address space and if the next page after the last page used by mmap is not owned by the process.

[taketwo]

Do you think #2261 is related?

[floriankramer]

I tried the steps you described in the issue with the patched version and was not able to reproduce the crash.
The compressed file is also 4112384 bytes large, which is 4096 * 1004 so it would fall into the category of files that should be affected by the bug (As the very last byte read would be in the next page, if I understand it properly).

[taketwo]

Thanks for the patch! Can confirm that that bug is solved.