# arch_prctl _________________________________________________
# long sys_arch_prctl(int code, unsigned long addr)
# SYSCALL_DEFINE2(arch_prctl, int, option, unsigned long, arg2)
# COMPAT_SYSCALL_DEFINE2(arch_prctl, int, option, unsigned long, arg2)
#
# NOTE: x86_64 only.
#

@define _SYSCALL_ARCH_PRCTL_NAME
%(
	name = "arch_prctl"
%)

@define _SYSCALL_ARCH_PRCTL_ARGSTR
%(
	argstr = sprintf("%s, %u", code_str, addr)
%)

@define _SYSCALL_ARCH_PRCTL_REGARGS
%(
	code = int_arg(1)
	code_str = _stp_arch_prctl_func_str(code)
	addr = ulong_arg(2)
%)

@define _SYSCALL_ARCH_PRCTL_REGARGS_STORE
%(
        if (@probewrite(code))
          set_int_arg(1, code)

	if (@probewrite(addr))
	  set_ulong_arg(2, addr)
%)

probe syscall.arch_prctl = dw_syscall.arch_prctl !,
                           nd_syscall.arch_prctl {}
probe syscall.arch_prctl.return = dw_syscall.arch_prctl.return !,
                                  nd_syscall.arch_prctl.return {}

# dw_arch_prctl _____________________________________________________

probe dw_syscall.arch_prctl = kernel.function("sys_arch_prctl").call,
	kernel.function("compat_sys_arch_prctl").call ?
{
	@_SYSCALL_ARCH_PRCTL_NAME
	code = __int32(@choose_defined($code, $option))
	code_str = _stp_arch_prctl_func_str(code)
	addr = __ulong(@choose_defined($addr, $arg2))
	@_SYSCALL_ARCH_PRCTL_ARGSTR
}
probe dw_syscall.arch_prctl.return = kernel.function("sys_arch_prctl").return,
	kernel.function("compat_sys_arch_prctl").return ?
{
	@_SYSCALL_ARCH_PRCTL_NAME
	@SYSC_RETVALSTR($return)
}

# nd_arch_prctl _____________________________________________________

probe nd_syscall.arch_prctl = nd1_syscall.arch_prctl!, nd2_syscall.arch_prctl!, tp_syscall.arch_prctl
  { }

probe nd1_syscall.arch_prctl = kprobe.function("sys_arch_prctl"),
	kprobe.function("compat_sys_arch_prctl") ?
{
	@_SYSCALL_ARCH_PRCTL_NAME
	// NB: no asmlinkage()
	@_SYSCALL_ARCH_PRCTL_REGARGS
	@_SYSCALL_ARCH_PRCTL_ARGSTR
}

/* kernel 4.17+ */
probe nd2_syscall.arch_prctl = kprobe.function(@arch_syscall_prefix "sys_arch_prctl"),
	kprobe.function(@arch_syscall_prefix "compat_sys_arch_prctl") ?
{
	__set_syscall_pt_regs(pointer_arg(1))
	@_SYSCALL_ARCH_PRCTL_NAME
	@_SYSCALL_ARCH_PRCTL_REGARGS
	@_SYSCALL_ARCH_PRCTL_ARGSTR
},
{
        %( @_IS_SREG_KERNEL %? @_SYSCALL_ARCH_PRCTL_REGARGS_STORE %)
}

/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.arch_prctl = kernel.trace("sys_enter")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_arch_prctl"), @const("__NR_ia32_arch_prctl"))
	@_SYSCALL_ARCH_PRCTL_NAME
	@_SYSCALL_ARCH_PRCTL_REGARGS
	@_SYSCALL_ARCH_PRCTL_ARGSTR
},
{
        %( @_IS_SREG_KERNEL %? @_SYSCALL_ARCH_PRCTL_REGARGS_STORE %)
}

probe nd_syscall.arch_prctl.return = nd1_syscall.arch_prctl.return!, nd2_syscall.arch_prctl.return!, tp_syscall.arch_prctl.return
  { }
  
probe nd1_syscall.arch_prctl.return = kprobe.function("sys_arch_prctl").return,
	kprobe.function("compat_sys_arch_prctl").return ?
{
	@_SYSCALL_ARCH_PRCTL_NAME
	@SYSC_RETVALSTR(returnval())
}

/* kernel 4.17+ */
probe nd2_syscall.arch_prctl.return = kprobe.function(@arch_syscall_prefix "sys_arch_prctl").return,
      kprobe.function(@arch_syscall_prefix "compat_sys_arch_prctl").return ?
{
	@_SYSCALL_ARCH_PRCTL_NAME
	@SYSC_RETVALSTR(returnval())
}
 
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.arch_prctl.return = kernel.trace("sys_exit")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_arch_prctl"), @const("__NR_ia32_arch_prctl"))
	@_SYSCALL_ARCH_PRCTL_NAME
	@SYSC_RETVALSTR($ret)
}
