glibc mmap incorrectly translates addr argument, breaking MAP_FIXED

[rishabhBudhouliya]

Bug

mmap.c and mmap64.c call TRANSLATE_GUEST_POINTER_TO_HOST(addr) on the address argument. Since addr is a guest virtual address and not a pointer to data, this causes unexpected memory allocation via mmap.

When using mmap (with MAP_FIXED flag) with non-NULL addr:

1. glibc translates: host_addr = base + addr
2. rawposix truncates 64-bit to 32-bit: useraddr = host_addr as u32
3. rawposix translates again: sysaddr = base + useraddr