1#@!#!123s

: / usr / share / systemtap / tapset / linux /
Filename : sysc_mount.stp
back
# mount ______________________________________________________
# long sys_mount(char __user * dev_name,
# 		char __user * dir_name,
# 		char __user * type,
# 		unsigned long flags,
# 		void __user * data)
# long compat_sys_mount(char __user * dev_name,
#		char __user * dir_name,
#		char __user * type,
#		unsigned long flags,
#		void __user * data)

@define _SYSCALL_MOUNT_NAME
%(
	name = "mount"
%)

@define _SYSCALL_MOUNT_ARGSTR
%(
	argstr = sprintf("%s, %s, %s, %s, %s",
	                 source, target, filesystemtype, mountflags_str, data)
%)

@define _SYSCALL_MOUNT_REGARGS
%(
	source = user_string_quoted(pointer_arg(1))
	target = user_string_quoted(pointer_arg(2))
	filesystemtype = user_string_quoted(pointer_arg(3))
	mountflags = ulong_arg(4)
	mountflags_str = _mountflags_str(mountflags)
	data = user_string_n_quoted(pointer_arg(5), syscall_string_trunc)
%)

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

# dw_mount _____________________________________________________

probe dw_syscall.mount = kernel.function("compat_sys_mount").call ?,
                      kernel.function("sys_mount").call
{
	@_SYSCALL_MOUNT_NAME
	source = user_string_quoted(@__pointer($dev_name))
	target = user_string_quoted(@__pointer($dir_name))
	filesystemtype = user_string_quoted(@__pointer($type))
	mountflags = @__compat_ulong($flags)
	mountflags_str = _mountflags_str(mountflags)
	data = user_string_n_quoted(@__pointer($data), syscall_string_trunc)
	@_SYSCALL_MOUNT_ARGSTR
}
probe dw_syscall.mount.return = kernel.function("compat_sys_mount").return ?,
                             kernel.function("sys_mount").return
{
	@_SYSCALL_MOUNT_NAME
	@SYSC_RETVALSTR($return)
}

# nd_mount _____________________________________________________

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

probe nd1_syscall.mount = kprobe.function("compat_sys_mount") ?,
                          kprobe.function("sys_mount") ?
{
	@_SYSCALL_MOUNT_NAME
	asmlinkage()
	@_SYSCALL_MOUNT_REGARGS
	@_SYSCALL_MOUNT_ARGSTR
}

/* kernel 4.17+ */
probe nd2_syscall.mount = kprobe.function(@arch_syscall_prefix "sys_mount") ?,
                          kprobe.function(@arch_syscall_prefix "compat_sys_mount") ?
{
	__set_syscall_pt_regs(pointer_arg(1))
	@_SYSCALL_MOUNT_NAME
	@_SYSCALL_MOUNT_REGARGS
	@_SYSCALL_MOUNT_ARGSTR
}

/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.mount = kernel.trace("sys_enter")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_mount"), @const("__NR_compat_mount"))
	@_SYSCALL_MOUNT_NAME
	@_SYSCALL_MOUNT_REGARGS
	@_SYSCALL_MOUNT_ARGSTR
}

probe nd_syscall.mount.return = nd1_syscall.mount.return!, nd2_syscall.mount.return!, tp_syscall.mount.return
  { }
  
probe nd1_syscall.mount.return = kprobe.function("compat_sys_mount").return ?,
                                 kprobe.function("sys_mount").return ?
{
	@_SYSCALL_MOUNT_NAME
	@SYSC_RETVALSTR(returnval())
}

/* kernel 4.17+ */
probe nd2_syscall.mount.return = kprobe.function(@arch_syscall_prefix "sys_mount").return ?,
                                 kprobe.function(@arch_syscall_prefix "compat_sys_mount").return ?
{
	@_SYSCALL_MOUNT_NAME
	@SYSC_RETVALSTR(returnval())
}
 
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.mount.return = kernel.trace("sys_exit")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_mount"), @const("__NR_compat_mount"))
	@_SYSCALL_MOUNT_NAME
	@SYSC_RETVALSTR($ret)
}