path: root/modules/pam_limits/pam_limits.8

.\"     Title: pam_limits
.\"    Author: [see the "AUTHORS" section]
.\" Generator: DocBook XSL Stylesheets v1.74.0 <http://docbook.sf.net/>
.\"      Date: 06/16/2009
.\"    Manual: Linux-PAM Manual
.\"    Source: Linux-PAM Manual
.\"  Language: English
.\"
.TH "PAM_LIMITS" "8" "06/16/2009" "Linux-PAM Manual" "Linux-PAM Manual"
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.SH "Name"
pam_limits \- PAM module to limit resources
.SH "Synopsis"
.fam C
.HP \w'\fBpam_limits\&.so\fR\ 'u
\fBpam_limits\&.so\fR [change_uid] [conf=\fI/path/to/limits\&.conf\fR] [debug] [utmp_early] [noaudit]
.fam
.SH "DESCRIPTION"
.PP
The pam_limits PAM module sets limits on the system resources that can be obtained in a user\-session\&. Users of
\fIuid=0\fR
are affected by this limits, too\&.
.PP
By default limits are taken from the
\FC/etc/security/limits\&.conf\F[]
config file\&. Then individual *\&.conf files from the
\FC/etc/security/limits\&.d/\F[]
directory are read\&. The files are parsed one after another in the order of "C" locale\&. The effect of the individual files is the same as if all the files were concatenated together in the order of parsing\&. If a config file is explicitly specified with a module option then the files in the above directory are not parsed\&.
.PP
The module must not be called by a multithreaded application\&.
.PP
If Linux PAM is compiled with audit support the module will report when it denies access based on limit of maximum number of concurrent login sessions\&.
.SH "OPTIONS"
.PP
\fBchange_uid\fR
.RS 4
Change real uid to the user for who the limits are set up\&. Use this option if you have problems like login not forking a shell for user who has no processes\&. Be warned that something else may break when you do this\&.
.RE
.PP
\fBconf=\fR\fB\fI/path/to/limits\&.conf\fR\fR
.RS 4
Indicate an alternative limits\&.conf style configuration file to override the default\&.
.RE
.PP
\fBdebug\fR
.RS 4
Print debug information\&.
.RE
.PP
\fButmp_early\fR
.RS 4
Some broken applications actually allocate a utmp entry for the user before the user is admitted to the system\&. If some of the services you are configuring PAM for do this, you can selectively use this module argument to compensate for this behavior and at the same time maintain system\-wide consistency with a single limits\&.conf file\&.
.RE
.PP
\fBnoaudit\fR
.RS 4
Do not report exceeded maximum logins count to the audit subsystem\&.
.RE
.SH "MODULE TYPES PROVIDED"
.PP
Only the
\fBsession\fR
module type is provided\&.
.SH "RETURN VALUES"
.PP
PAM_ABORT
.RS 4
Cannot get current limits\&.
.RE
.PP
PAM_IGNORE
.RS 4
No limits found for this user\&.
.RE
.PP
PAM_PERM_DENIED
.RS 4
New limits could not be set\&.
.RE
.PP
PAM_SERVICE_ERR
.RS 4
Cannot read config file\&.
.RE
.PP
PAM_SESSION_ERR
.RS 4
Error recovering account name\&.
.RE
.PP
PAM_SUCCESS
.RS 4
Limits were changed\&.
.RE
.PP
PAM_USER_UNKNOWN
.RS 4
The user is not known to the system\&.
.RE
.SH "FILES"
.PP
\FC/etc/security/limits\&.conf\F[]
.RS 4
Default configuration file
.RE
.SH "EXAMPLES"
.PP
For the services you need resources limits (login for example) put a the following line in
\FC/etc/pam\&.d/login\F[]
as the last line for that service (usually after the pam_unix session line):
.sp
.if n \{\
.RS 4
.\}
.fam C
.ps -1
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#%PAM\-1\&.0
#
# Resource limits imposed on login sessions via pam_limits
#
session  required  pam_limits\&.so
    
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.sp 1
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.fam
.ps +1
.if n \{\
.RE
.\}
.PP
Replace "login" for each service you are using this module\&.
.SH "SEE ALSO"
.PP

\fBlimits.conf\fR(5),
\fBpam.d\fR(5),
\fBpam\fR(8)\&.
.SH "AUTHORS"
.PP
pam_limits was initially written by Cristian Gafton <gafton@redhat\&.com>