.\" Copyright (c) 2019 The FreeBSD Foundation
.\"
.\" This documentation was written by
.\" Konstantin Belousov <kib@FreeBSD.org> under sponsorship
.\" from the FreeBSD Foundation.
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.Dd August 23, 2024
.Dt PROCCONTROL 1
.Os
.Sh NAME
.Nm proccontrol
.Nd Control some process execution aspects
.Sh SYNOPSIS
.Nm
.Fl m Ar mode
.Fl s Ar control
.Fl p Ar pid | command
.Nm
.Fl m Ar mode
.Fl q
.Op Fl p Ar pid | command
.Sh DESCRIPTION
The
.Nm
command modifies the execution parameter of existing process
specified by the
.Ar pid
argument, or starts execution of the new program
.Ar command
with the execution parameter set for it.
.Pp
Which execution parameter is changed, selected by the mandatory
parameter
.Ar mode .
Possible values for
.Ar mode
are:
.Bl -tag -width trapcap
.It Ar aslr
Control the Address Space Layout Randomization.
Only applicable to the new process spawned.
.It Ar trace
Control the permission for debuggers to attach.
Note that process is only allowed to enable tracing for itself,
not for any other process.
.It Ar trapcap
Controls the signalling of capability mode access violations.
.It Ar protmax
Controls the implicit PROT_MAX application for
.Xr mmap 2 .
.It Ar nonewprivs
Controls disabling the setuid and sgid bits for
.Xr execve 2 .
.It Ar wxmap
Controls the write exclusive execute mode for mappings.
.It Ar kpti
Controls the KPTI enable, AMD64 only.
.It Ar la48
Control limiting usermode process address space to 48 bits of address,
AMD64 only, on machines capable of 57-bit addressing.
.El
.Pp
The
.Ar control
specifies if the selected
.Ar mode
should be enabled or disabled.
Possible values are
.Ar enable
and
.Ar disable ,
with the default value being
.Ar enable
if not specified.
See
.Xr procctl 2
for detailed description of each mode effects and interaction with other
process control facilities.
.Pp
The
.Fl q
switch makes the utility query and print the current setting for
the selected mode.
The
.Fl q
requires the query target process specification with
.Fl p .
.Sh EXIT STATUS
.Ex -std
.Sh EXAMPLES
.Bl -bullet
.It
To disable debuggers attachment to the process 1020, execute
.Dl "proccontrol -m trace -s disable -p 1020"
.It
To execute the
.Xr uniq 1
program in a mode where capability access violations cause
.Dv SIGTRAP
delivery, do
.Dl "proccontrol -m trapcap uniq"
.It
To query the current ASLR enablement mode for the running
process 1020, do
.Dl "proccontrol -m aslr -q -p 1020"
.El
.Sh SEE ALSO
.Xr kill 2 ,
.Xr procctl 2 ,
.Xr ptrace 2 ,
.Xr mitigations 7
.Sh HISTORY
The
.Nm
command appeared in
.Fx 10.0 .
.Sh AUTHORS
The
.Nm
command and this manual page were written by
.An Konstantin Belousov Aq Mt kib@freebsd.org
under sponsorship from The FreeBSD Foundation.