Failing to load mach-o correctly may lead to segment fault

[4B5F5F4B]

Hi all,

While trying your tool I came across some segment fault like the issue posted here.

#25

I spent some time to debug the root cause of mentioned bug, I find dsdump doesn't load mach-o into memory correctly. The author naively mapped mach-o file into memory through mmap(. You can find the following code in XRMachOLibrary.mm

void* buff = ::mmap((void*)0x0000000400000000UL, fsize, PROT_READ, MAP_PRIVATE, self.fd, 0);
payload::data = (uint8_t *)buff; // self.data;
payload::size = fsize;

In fact you'd better parse all segments carefully.