The following code is wrong: http://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/vbe/vbe.c?h=server-1.9-branch#n589 Here the code tries to copy 206 bytes. In the other case (VESA 3.0 supported), only 188 + 66 - 50 = 204 bytes are copied. VirtualBox supports only VESA 2.0, therefore the crash. The memcpy function is compiled with fortify enabled. This leads to a crash when fortify is enabled.
Note the the other else case for VESA < 2.0 is wrong as well (216 versus 215 bytes).
*** This bug has been marked as a duplicate of bug 30159 ***
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.