radare2: Uncontrolled memory allocation in radare2 dmp64 parser

radare2 is a UNIX-like reverse engineering framework and command-line toolset. Prior to 6.2.0, radare2's Windows 64-bit crash-dump dmp64 parser was vulnerable because the Windows dmp64 parser used an input-controlled physical-memory-run PageCount directly as the bound of a per-page allocation loop. The vulnerability is triggered by opening a small crafted full-memory Windows crash dump. The parser repeatedly allocated and appended page descriptors without validating the count against the dump size. This can cause denial of service through excessive memory consumption and processing time. This issue is fixed in version 6.2.0.