The register R12 has a special meaning when syscalls are hooked
with ptrace() in ARM that results in a dumpee context corruption
on an injected blob unmap. Note that this patch doesn't solve
the problem entirely since the compiler may corrupt the register
before issuing a call to the routine sys_munmap(); however
we assume that a sufficiently decent compiler doesn't.
Signed-off-by: Alexander Kartashov <alekskartashov@parallels.com>
Tested-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>