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# readlink ___________________________________________________
#
# long sys_readlink(const char __user * path,
# char __user * buf,
# int bufsiz)
#
@define _SYSCALL_READLINK_NAME
%(
name = "readlink"
%)
@define _SYSCALL_READLINK_ARGSTR
%(
argstr = sprintf("%s, %p, %d", path, buf_uaddr, bufsiz)
%)
@define _SYSCALL_READLINK_REGARGS
%(
path = user_string_quoted(pointer_arg(1))
path_unquoted = user_string_nofault(pointer_arg(1))
buf_uaddr = pointer_arg(2)
bufsiz = int_arg(3)
%)
@define _SYSCALL_READLINK_REGARGS_STORE
%(
if (@probewrite(path_unquoted))
set_user_string_arg(pointer_arg(1), path_unquoted)
if (@probewrite(buf_uaddr))
set_pointer_arg(2, buf_uaddr)
if (@probewrite(bufsiz))
set_int_arg(3, bufsiz)
%)
probe syscall.readlink = dw_syscall.readlink !, nd_syscall.readlink ? {}
probe syscall.readlink.return = dw_syscall.readlink.return !,
nd_syscall.readlink.return ? {}
# dw_readlink _____________________________________________________
probe dw_syscall.readlink = kernel.function("sys_readlink").call
{
@_SYSCALL_READLINK_NAME
path = user_string_quoted($path)
buf_uaddr = $buf
bufsiz = __int32($bufsiz)
@_SYSCALL_READLINK_ARGSTR
}
probe dw_syscall.readlink.return = kernel.function("sys_readlink").return
{
@_SYSCALL_READLINK_NAME
@SYSC_RETVALSTR($return)
}
# nd_readlink _____________________________________________________
probe nd_syscall.readlink = nd1_syscall.readlink!, nd2_syscall.readlink!, tp_syscall.readlink
{ }
probe nd1_syscall.readlink = kprobe.function("sys_readlink") ?
{
@_SYSCALL_READLINK_NAME
asmlinkage()
@_SYSCALL_READLINK_REGARGS
@_SYSCALL_READLINK_ARGSTR
}
/* kernel 4.17+ */
probe nd2_syscall.readlink = kprobe.function(@arch_syscall_prefix "sys_readlink") ?
{
__set_syscall_pt_regs(pointer_arg(1))
@_SYSCALL_READLINK_NAME
@_SYSCALL_READLINK_REGARGS
@_SYSCALL_READLINK_ARGSTR
},
{
%( @_IS_SREG_KERNEL %? @_SYSCALL_READLINK_REGARGS_STORE %)
}
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.readlink = kernel.trace("sys_enter")
{
__set_syscall_pt_regs($regs)
@__syscall_compat_gate(@const("__NR_readlink"), @const("__NR_compat_readlink"))
@_SYSCALL_READLINK_NAME
@_SYSCALL_READLINK_REGARGS
@_SYSCALL_READLINK_ARGSTR
},
{
%( @_IS_SREG_KERNEL %? @_SYSCALL_READLINK_REGARGS_STORE %)
}
probe nd_syscall.readlink.return = nd1_syscall.readlink.return!, nd2_syscall.readlink.return!, tp_syscall.readlink.return
{ }
probe nd1_syscall.readlink.return = kprobe.function("sys_readlink").return ?
{
@_SYSCALL_READLINK_NAME
@SYSC_RETVALSTR(returnval())
}
/* kernel 4.17+ */
probe nd2_syscall.readlink.return = kprobe.function(@arch_syscall_prefix "sys_readlink").return ?
{
@_SYSCALL_READLINK_NAME
@SYSC_RETVALSTR(returnval())
}
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.readlink.return = kernel.trace("sys_exit")
{
__set_syscall_pt_regs($regs)
@__syscall_compat_gate(@const("__NR_readlink"), @const("__NR_compat_readlink"))
@_SYSCALL_READLINK_NAME
@SYSC_RETVALSTR($ret)
}
|
