uprobes: fix kernel info leak via "[uprobes]" vma
In the Linux kernel, the following vulnerability has been resolved:

uprobes: fix kernel info leak via "[uprobes]" vma

xol_add_vma() maps the uninitialized page allocated by __create_xol_area()
into userspace. On some architectures (x86) this memory is readable even
without VM_READ, VM_EXEC results in the same pgprot_t as VM_EXEC|VM_READ,
although this doesn't really matter, debugger can read this memory anyway.