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|
# setgid _____________________________________________________
#
# long sys_setgid(gid_t gid)
# long sys_setgid16(old_gid_t gid)
#
@define _SYSCALL_SETGID_NAME
%(
name = "setgid"
%)
@define _SYSCALL_SETGID_ARGSTR
%(
argstr = sprint(gid)
%)
@define _SYSCALL_GATE
%(
%( arch == "x86_64" %?
// There are actually 3 x86_64 setgid syscalls numbers (which
// get mapped to 2 syscall functions:
// - __NR_setgid which gets mapped to sys_setgid()
// - __NR_ia32_setgid32 which also gets mapped to
// sys_setgid()
// - __NR_ia32_setgid which gets mapped to sys_setgid16()
// (which is a wrapper around sys_setgid())
// So, we need to avoid sys_setgid() calls that come from
// sys_setgid16().
@__syscall_compat_gate(@const("__NR_setgid"),
@const("__NR_ia32_setgid32"))
%:
%( arch == "i386" %?
// On i386, there are 2 setgid syscall numbers:
// - __NR_setgid which gets mapped to sys_setgid16
// - __NR_setgid32 which gets mapped to sys_setgid
// Since this gets called from a probe on sys_setgid, we'll
// make sure this is really __NR_setgid32.
@__syscall_nr_gate(@const("__NR_setgid32"))
%)
%)
%)
@define _SYSCALL_SETGID_REGARGS
%(
gid = int_arg(1)
%)
@define _SYSCALL_SETGID_REGARGS_STORE
%(
if (@probewrite(gid))
set_int_arg(1, gid)
%)
probe syscall.setgid = dw_syscall.setgid !, nd_syscall.setgid ? {}
probe syscall.setgid.return = dw_syscall.setgid.return !,
nd_syscall.setgid.return ? {}
# dw_setgid _____________________________________________________
probe dw_syscall.setgid = kernel.function("sys_setgid16").call ?,
__syscall.setgid ?
{
@_SYSCALL_SETGID_NAME
gid = __int32($gid)
@_SYSCALL_SETGID_ARGSTR
}
probe __syscall.setgid = kernel.function("sys_setgid").call ?
{
@_SYSCALL_GATE
}
probe dw_syscall.setgid.return = kernel.function("sys_setgid16").return ?,
__syscall.setgid.return ?
{
@_SYSCALL_SETGID_NAME
@SYSC_RETVALSTR($return)
}
probe __syscall.setgid.return = kernel.function("sys_setgid").return ?
{
@_SYSCALL_GATE
}
# nd_setgid _____________________________________________________
probe nd_syscall.setgid = nd1_syscall.setgid!, nd2_syscall.setgid!, tp_syscall.setgid
{ }
probe nd1_syscall.setgid = kprobe.function("sys_setgid16") ?,
__nd1_syscall.setgid ?
{
@_SYSCALL_SETGID_NAME
asmlinkage()
@_SYSCALL_SETGID_REGARGS
@_SYSCALL_SETGID_ARGSTR
}
probe __nd1_syscall.setgid = kprobe.function("sys_setgid") ?
{
@_SYSCALL_GATE
}
/* kernel 4.17+ */
probe nd2_syscall.setgid = kprobe.function(@arch_syscall_prefix "sys_setgid") ?,
kprobe.function(@arch_syscall_prefix "sys_setgid16") ?
{
__set_syscall_pt_regs(pointer_arg(1))
@_SYSCALL_SETGID_NAME
@_SYSCALL_SETGID_REGARGS
@_SYSCALL_SETGID_ARGSTR
},
{
%( @_IS_SREG_KERNEL %? @_SYSCALL_SETGID_REGARGS_STORE %)
}
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.setgid = __tp_syscall.setgid, __tp_syscall.setgid16
{
__set_syscall_pt_regs($regs)
@_SYSCALL_SETGID_NAME
@_SYSCALL_SETGID_REGARGS
@_SYSCALL_SETGID_ARGSTR
},
{
%( @_IS_SREG_KERNEL %? @_SYSCALL_SETGID_REGARGS_STORE %)
}
probe __tp_syscall.setgid = kernel.trace("sys_enter")
{
@__syscall_compat_gate(@const("__NR_setgid"), @const("__NR_compat_setgid32"))
}
probe __tp_syscall.setgid16 = kernel.trace("sys_enter")
{
@__compat_syscall_gate(@const("__NR_compat_setgid"))
}
probe nd_syscall.setgid.return = nd1_syscall.setgid.return!, nd2_syscall.setgid.return!, tp_syscall.setgid.return
{ }
probe nd1_syscall.setgid.return = kprobe.function("sys_setgid16").return ?,
__nd1_syscall.setgid.return ?
{
@_SYSCALL_SETGID_NAME
@SYSC_RETVALSTR(returnval())
}
probe __nd1_syscall.setgid.return = kprobe.function("sys_setgid").return ?
{
@_SYSCALL_GATE
}
/* kernel 4.17+ */
probe nd2_syscall.setgid.return =
kprobe.function(@arch_syscall_prefix "sys_setgid").return ?,
kprobe.function(@arch_syscall_prefix "sys_setgid16").return ?
{
@_SYSCALL_SETGID_NAME
@SYSC_RETVALSTR(returnval())
}
/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.setgid.return = __tp_syscall.setgid.return, __tp_syscall.setgid16.return
{
__set_syscall_pt_regs($regs)
@_SYSCALL_SETGID_NAME
@SYSC_RETVALSTR($ret)
}
probe __tp_syscall.setgid.return = kernel.trace("sys_exit")
{
@__syscall_compat_gate(@const("__NR_setgid"), @const("__NR_compat_setgid32"))
}
probe __tp_syscall.setgid16.return = kernel.trace("sys_exit")
{
@__compat_syscall_gate(@const("__NR_compat_setgid"))
}
|
