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|
# setuid _____________________________________________________
#
# long sys_setuid(uid_t uid)
# long sys_setuid16(old_uid_t uid)
#
@define _SYSCALL_SETUID_NAME
%(
name = "setuid"
%)
@define _SYSCALL_SETUID_ARGSTR
%(
argstr = sprint(uid)
%)
@define _SYSCALL_GATE
%(
%( arch == "x86_64" %?
// There are actually 3 x86_64 setuid syscall numbers (which
// get mapped to 2 syscall functions:
// - __NR_setuid which gets mapped to sys_setuid()
// - __NR_ia32_setuid32 which also gets mapped to
// sys_setuid()
// - __NR_ia32_setuid which gets mapped to sys_setuid16()
// (which is a wrapper around sys_setuid())
// So, we need to avoid sys_setuid() calls that come from
// sys_setuid16().
@__syscall_compat_gate(@const("__NR_setuid"),
@const("__NR_ia32_setuid32"))
%:
%( arch == "i386" %?
// On i386, there are 2 setuid syscall numbers:
// - __NR_setuid which gets mapped to sys_setuid16
// - __NR_setuid32 which gets mapped to sys_setuid
// Since this gets called from a probe on sys_setuid, we'll
// make sure this is really __NR_setuid32.
@__syscall_nr_gate(@const("__NR_setuid32"))
%)
%)
%)
@define _SYSCALL_SETUID_REGARGS
%(
uid = int_arg(1)
%)
@define _SYSCALL_SETUID_REGARGS_STORE
%(
if (@probewrite(uid))
set_int_arg(1, uid)
%)
probe syscall.setuid = dw_syscall.setuid !, nd_syscall.setuid ? {}
probe syscall.setuid.return = dw_syscall.setuid.return !,
nd_syscall.setuid.return ? {}
# dw_setuid _____________________________________________________
probe dw_syscall.setuid = kernel.function("sys_setuid16").call ?,
__syscall.setuid ?
{
@_SYSCALL_SETUID_NAME
uid = __int32($uid)
@_SYSCALL_SETUID_ARGSTR
}
probe __syscall.setuid = kernel.function("sys_setuid").call ?
{
@_SYSCALL_GATE
}
probe dw_syscall.setuid.return = kernel.function("sys_setuid16").return ?,
__syscall.setuid.return ?
{
@_SYSCALL_SETUID_NAME
@SYSC_RETVALSTR($return)
}
probe __syscall.setuid.return = kernel.function("sys_setuid").return ?
{
@_SYSCALL_GATE
}
# nd_setuid _____________________________________________________
probe nd_syscall.setuid = nd1_syscall.setuid!, nd2_syscall.setuid!, tp_syscall.setuid
{ }
probe nd1_syscall.setuid = kprobe.function("sys_setuid16") ?,
__nd1_syscall.setuid ?
{
@_SYSCALL_SETUID_NAME
asmlinkage()
@_SYSCALL_SETUID_REGARGS
@_SYSCALL_SETUID_ARGSTR
}
probe __nd1_syscall.setuid = kprobe.function("sys_setuid") ?
{
@_SYSCALL_GATE
}
/* kernel 4.17+ */
probe nd2_syscall.setuid = kprobe.function(@arch_syscall_prefix "sys_setuid") ?,
kprobe.function(@arch_syscall_prefix "sys_setuid16") ?
{
__set_syscall_pt_regs(pointer_arg(1))
@_SYSCALL_SETUID_NAME
@_SYSCALL_SETUID_REGARGS
@_SYSCALL_SETUID_ARGSTR
},
{
%( @_IS_SREG_KERNEL %? @_SYSCALL_SETUID_REGARGS_STORE %)
}
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.setuid = __tp_syscall.setuid, __tp_syscall.setuid16
{
__set_syscall_pt_regs($regs)
@_SYSCALL_SETUID_NAME
@_SYSCALL_SETUID_REGARGS
@_SYSCALL_SETUID_ARGSTR
},
{
%( @_IS_SREG_KERNEL %? @_SYSCALL_SETUID_REGARGS_STORE %)
}
probe __tp_syscall.setuid = kernel.trace("sys_enter")
{
@__syscall_compat_gate(@const("__NR_setuid"), @const("__NR_compat_setuid32"))
}
probe __tp_syscall.setuid16 = kernel.trace("sys_enter")
{
@__compat_syscall_gate(@const("__NR_compat_setuid"))
}
probe nd_syscall.setuid.return = nd1_syscall.setuid.return!, nd2_syscall.setuid.return!, tp_syscall.setuid.return
{ }
probe nd1_syscall.setuid.return = kprobe.function("sys_setuid16").return ?,
__nd1_syscall.setuid.return ?
{
@_SYSCALL_SETUID_NAME
@SYSC_RETVALSTR(returnval())
}
probe __nd1_syscall.setuid.return = kprobe.function("sys_setuid").return ?
{
@_SYSCALL_GATE
}
/* kernel 4.17+ */
probe nd2_syscall.setuid.return =
kprobe.function(@arch_syscall_prefix "sys_setuid").return ?,
kprobe.function(@arch_syscall_prefix "sys_setuid16").return ?
{
@_SYSCALL_SETUID_NAME
@SYSC_RETVALSTR(returnval())
}
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.setuid.return = __tp_syscall.setuid.return, __tp_syscall.setuid16.return
{
__set_syscall_pt_regs($regs)
@_SYSCALL_SETUID_NAME
@SYSC_RETVALSTR($ret)
}
probe __tp_syscall.setuid.return = kernel.trace("sys_exit")
{
@__syscall_compat_gate(@const("__NR_setuid"), @const("__NR_compat_setuid32"))
}
probe __tp_syscall.setuid16.return = kernel.trace("sys_exit")
{
@__compat_syscall_gate(@const("__NR_compat_setuid"))
}
|
