1#@!#!123s

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Filename : sysc_getcwd.stp
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# getcwd _____________________________________________________
# long sys_getcwd(char __user *buf, unsigned long size)

@define _SYSCALL_GETCWD_NAME
%(
	name = "getcwd"
%)

@define _SYSCALL_GETCWD_ARGSTR
%(
	argstr = sprintf("%p, %d", buf_uaddr, size)
%)

@define _SYSCALL_GETCWD_REGARGS
%(
	buf_uaddr = pointer_arg(1)
	size = ulong_arg(2)
%)

probe syscall.getcwd = dw_syscall.getcwd !, nd_syscall.getcwd ? {}
probe syscall.getcwd.return = dw_syscall.getcwd.return !, nd_syscall.getcwd.return ? {}

# dw_getcwd _____________________________________________________
# long sys_getcwd(char __user *buf, unsigned long size)
probe dw_syscall.getcwd = kernel.function("sys_getcwd").call
{
	@_SYSCALL_GETCWD_NAME
	buf_uaddr = $buf
	size = $size
	@_SYSCALL_GETCWD_ARGSTR
}
probe dw_syscall.getcwd.return = kernel.function("sys_getcwd").return
{
	@_SYSCALL_GETCWD_NAME
	@SYSC_RETVALSTR($return)
}

# nd_getcwd _____________________________________________________
# long sys_getcwd(char __user *buf, unsigned long size)
#
probe nd_syscall.getcwd = nd1_syscall.getcwd!, nd2_syscall.getcwd!, tp_syscall.getcwd
  { }

probe nd1_syscall.getcwd = kprobe.function("sys_getcwd") ?
{
	@_SYSCALL_GETCWD_NAME
	asmlinkage()
	@_SYSCALL_GETCWD_REGARGS
	@_SYSCALL_GETCWD_ARGSTR
}

/* kernel 4.17+ */
probe nd2_syscall.getcwd = kprobe.function(@arch_syscall_prefix "sys_getcwd") ?
{
	__set_syscall_pt_regs(pointer_arg(1))
	@_SYSCALL_GETCWD_NAME
	@_SYSCALL_GETCWD_REGARGS
	@_SYSCALL_GETCWD_ARGSTR
}

/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.getcwd = kernel.trace("sys_enter")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_getcwd"), @const("__NR_compat_getcwd"))
	@_SYSCALL_GETCWD_NAME
	@_SYSCALL_GETCWD_REGARGS
	@_SYSCALL_GETCWD_ARGSTR
}

probe nd_syscall.getcwd.return = nd1_syscall.getcwd.return!, nd2_syscall.getcwd.return!, tp_syscall.getcwd.return
  { }

probe nd1_syscall.getcwd.return = kprobe.function("sys_getcwd").return ?
{
	@_SYSCALL_GETCWD_NAME
	@SYSC_RETVALSTR(returnval())
}

/* kernel 4.17+ */
probe nd2_syscall.getcwd.return = kprobe.function(@arch_syscall_prefix "sys_getcwd").return ?
{
	@_SYSCALL_GETCWD_NAME
	@SYSC_RETVALSTR(returnval())
}

/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.getcwd.return = kernel.trace("sys_exit")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_getcwd"), @const("__NR_compat_getcwd"))
	@_SYSCALL_GETCWD_NAME
	@SYSC_RETVALSTR($ret)
}