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udo -u postgres createuser owning_userq:q
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SUDO(8) BSD System Manager's Manual SUDO(8)
NNAAMMEE
ssuuddoo, ssuuddooeeddiitt — execute a command as another user
SSYYNNOOPPSSIISS
ssuuddoo --hh | --KK | --kk | --VV
ssuuddoo --vv [--AABBkknnSS] [--gg _g_r_o_u_p] [--hh _h_o_s_t] [--pp _p_r_o_m_p_t] [--uu _u_s_e_r]
ssuuddoo --ll [--AABBkknnSS] [--gg _g_r_o_u_p] [--hh _h_o_s_t] [--pp _p_r_o_m_p_t] [--UU _u_s_e_r] [--uu _u_s_e_r] [_c_o_m_m_a_n_d]
ssuuddoo [--AABBbbEEHHnnPPSS] [--CC _n_u_m] [--gg _g_r_o_u_p] [--hh _h_o_s_t] [--pp _p_r_o_m_p_t] [--rr _r_o_l_e] [--tt _t_y_p_e] [--TT _t_i_m_e_o_u_t] [--uu _u_s_e_r] [_V_A_R=_v_a_l_u_e] [--ii | --ss]
[_c_o_m_m_a_n_d]
ssuuddooeeddiitt [--AABBkknnSS] [--CC _n_u_m] [--gg _g_r_o_u_p] [--hh _h_o_s_t] [--pp _p_r_o_m_p_t] [--TT _t_i_m_e_o_u_t] [--uu _u_s_e_r] _f_i_l_e _._._.
DDEESSCCRRIIPPTTIIOONN
ssuuddoo allows a permitted user to execute a _c_o_m_m_a_n_d as the superuser or another user, as specified by the security policy. The
invoking user's real (_n_o_t effective) user-ID is used to determine the user name with which to query the security policy.
ssuuddoo supports a plugin architecture for security policies and input/output logging. Third parties can develop and distribute
their own policy and I/O logging plugins to work seamlessly with the ssuuddoo front end. The default security policy is _s_u_d_o_e_r_s,
which is configured via the file _/_e_t_c_/_s_u_d_o_e_r_s, or via LDAP. See the _P_l_u_g_i_n_s section for more information.
The security policy determines what privileges, if any, a user has to run ssuuddoo. The policy may require that users authenticate
themselves with a password or another authentication mechanism. If authentication is required, ssuuddoo will exit if the user's
password is not entered within a configurable time limit. This limit is policy-specific; the default password prompt timeout
for the _s_u_d_o_e_r_s security policy is 0 minutes.
Security policies may support credential caching to allow the user to run ssuuddoo again for a period of time without requiring au‐
thentication. By default, the _s_u_d_o_e_r_s policy caches credentials on a per-terminal basis for 15 minutes. See the _t_i_m_e_s_t_a_m_p___t_y_p_e
and _t_i_m_e_s_t_a_m_p___t_i_m_e_o_u_t options in sudoers(5) for more information. By running ssuuddoo with the --vv option, a user can update the
cached credentials without running a _c_o_m_m_a_n_d.
When invoked as ssuuddooeeddiitt, the --ee option (described below), is implied.
Security policies may log successful and failed attempts to use ssuuddoo. If an I/O plugin is configured, the running command's in‐
put and output may be logged as well.
The options are as follows:
--AA, ----aasskkppaassss
Normally, if ssuuddoo requires a password, it will read it from the user's terminal. If the --AA (_a_s_k_p_a_s_s) option is
specified, a (possibly graphical) helper program is executed to read the user's password and output the password to
the standard output. If the SUDO_ASKPASS environment variable is set, it specifies the path to the helper program.
Otherwise, if sudo.conf(5) contains a line specifying the askpass program, that value will be used. For example:
# Path to askpass helper program
Path askpass /usr/X11R6/bin/ssh-askpass
If no askpass program is available, ssuuddoo will exit with an error.
--BB, ----bbeellll Ring the bell as part of the password promp when a terminal is present. This option has no effect if an askpass
program is used.
--bb, ----bbaacckkggrroouunndd
Run the given command in the background. Note that it is not possible to use shell job control to manipulate back‐
ground processes started by ssuuddoo. Most interactive commands will fail to work properly in background mode.
--CC _n_u_m, ----cclloossee--ffrroomm=_n_u_m
Close all file descriptors greater than or equal to _n_u_m before executing a command. Values less than three are not
permitted. By default, ssuuddoo will close all open file descriptors other than standard input, standard output and
standard error when executing a command. The security policy may restrict the user's ability to use this option.
The _s_u_d_o_e_r_s policy only permits use of the --CC option when the administrator has enabled the _c_l_o_s_e_f_r_o_m___o_v_e_r_r_i_d_e op‐
tion.
--EE, ----pprreesseerrvvee--eennvv
Indicates to the security policy that the user wishes to preserve their existing environment variables. The secu‐
rity policy may return an error if the user does not have permission to preserve the environment.
----pprreesseerrvvee--eennvv==lliisstt
Indicates to the security policy that the user wishes to add the comma-separated list of environment variables to
those preserved from the user's environment. The security policy may return an error if the user does not have per‐
mission to preserve the environment.
--ee, ----eeddiitt Edit one or more files instead of running a command. In lieu of a path name, the string "sudoedit" is used when
consulting the security policy. If the user is authorized by the policy, the following steps are taken:
1. Temporary copies are made of the files to be edited with the owner set to the invoking user.
2. The editor specified by the policy is run to edit the temporary files. The _s_u_d_o_e_r_s policy uses the
SUDO_EDITOR, VISUAL and EDITOR environment variables (in that order). If none of SUDO_EDITOR, VISUAL or EDITOR
are set, the first program listed in the _e_d_i_t_o_r sudoers(5) option is used.
3. If they have been modified, the temporary files are copied back to their original location and the temporary
versions are removed.
To help prevent the editing of unauthorized files, the following restrictions are enforced unless explicitly allowed
by the security policy:
•• Symbolic links may not be edited (version 1.8.15 and higher).
•• Symbolic links along the path to be edited are not followed when the parent directory is writable by the invoking
user unless that user is root (version 1.8.16 and higher).
•• Files located in a directory that is writable by the invoking user may not be edited unless that user is root
(version 1.8.16 and higher).
Users are never allowed to edit device special files.
If the specified file does not exist, it will be created. Note that unlike most commands run by _s_u_d_o, the editor is
run with the invoking user's environment unmodified. If, for some reason, ssuuddoo is unable to update a file with its
edited version, the user will receive a warning and the edited copy will remain in a temporary file.
--gg _g_r_o_u_p, ----ggrroouupp=_g_r_o_u_p
Run the command with the primary group set to _g_r_o_u_p instead of the primary group specified by the target user's
password database entry. The _g_r_o_u_p may be either a group name or a numeric group-ID (GID) prefixed with the ‘#’
character (e.g., #0 for GID 0). When running a command as a GID, many shells require that the ‘#’ be escaped with a
backslash (‘\’). If no --uu option is specified, the command will be run as the invoking user. In either case, the
primary group will be set to _g_r_o_u_p. The _s_u_d_o_e_r_s policy permits any of the target user's groups to be specified via
the --gg option as long as the --PP option is not in use.
--HH, ----sseett--hhoommee
Request that the security policy set the HOME environment variable to the home directory specified by the target
user's password database entry. Depending on the policy, this may be the default behavior.
--hh, ----hheellpp Display a short help message to the standard output and exit.
--hh _h_o_s_t, ----hhoosstt=_h_o_s_t
Run the command on the specified _h_o_s_t if the security policy plugin supports remote commands. Note that the _s_u_d_o_e_r_s
plugin does not currently support running remote commands. This may also be used in conjunction with the --ll option
to list a user's privileges for the remote host.
--ii, ----llooggiinn
Run the shell specified by the target user's password database entry as a login shell. This means that login-spe‐
cific resource files such as _._p_r_o_f_i_l_e, _._b_a_s_h___p_r_o_f_i_l_e or _._l_o_g_i_n will be read by the shell. If a command is speci‐
fied, it is passed to the shell for execution via the shell's --cc option. If no command is specified, an interactive
shell is executed. ssuuddoo attempts to change to that user's home directory before running the shell. The command is
run with an environment similar to the one a user would receive at log in. Note that most shells behave differently
when a command is specified as compared to an interactive session; consult the shell's manual for details. The
_C_o_m_m_a_n_d _e_n_v_i_r_o_n_m_e_n_t section in the sudoers(5) manual documents how the --ii option affects the environment in which a
command is run when the _s_u_d_o_e_r_s policy is in use.
--KK, ----rreemmoovvee--ttiimmeessttaammpp
Similar to the --kk option, except that it removes the user's cached credentials entirely and may not be used in con‐
junction with a command or other option. This option does not require a password. Not all security policies sup‐
port credential caching.
--kk, ----rreesseett--ttiimmeessttaammpp
When used without a command, invalidates the user's cached credentials. In other words, the next time ssuuddoo is run a
password will be required. This option does not require a password and was added to allow a user to revoke ssuuddoo
permissions from a _._l_o_g_o_u_t file.
When used in conjunction with a command or an option that may require a password, this option will cause ssuuddoo to ig‐
nore the user's cached credentials. As a result, ssuuddoo will prompt for a password (if one is required by the secu‐
rity policy) and will not update the user's cached credentials.
Not all security policies support credential caching.
--ll, ----lliisstt If no _c_o_m_m_a_n_d is specified, list the allowed (and forbidden) commands for the invoking user (or the user specified
by the --UU option) on the current host. A longer list format is used if this option is specified multiple times and
the security policy supports a verbose output format.
If a _c_o_m_m_a_n_d is specified and is permitted by the security policy, the fully-qualified path to the command is dis‐
played along with any command line arguments. If a _c_o_m_m_a_n_d is specified but not allowed by the policy, ssuuddoo will
exit with a status value of 1.
--nn, ----nnoonn--iinntteerraaccttiivvee
Avoid prompting the user for input of any kind. If a password is required for the command to run, ssuuddoo will display
an error message and exit.
--PP, ----pprreesseerrvvee--ggrroouuppss
Preserve the invoking user's group vector unaltered. By default, the _s_u_d_o_e_r_s policy will initialize the group vec‐
tor to the list of groups the target user is a member of. The real and effective group-IDs, however, are still set
to match the target user.
--pp _p_r_o_m_p_t, ----pprroommpptt=_p_r_o_m_p_t
Use a custom password prompt with optional escape sequences. The following percent (‘%’) escape sequences are sup‐
ported by the _s_u_d_o_e_r_s policy:
%H expanded to the host name including the domain name (on if the machine's host name is fully qualified or the
_f_q_d_n option is set in sudoers(5))
%h expanded to the local host name without the domain name
%p expanded to the name of the user whose password is being requested (respects the _r_o_o_t_p_w, _t_a_r_g_e_t_p_w, and _r_u_n_a_s_p_w
flags in sudoers(5))
%U expanded to the login name of the user the command will be run as (defaults to root unless the --uu option is also
specified)
%u expanded to the invoking user's login name
%% two consecutive ‘%’ characters are collapsed into a single ‘%’ character
The custom prompt will override the default prompt specified by either the security policy or the SUDO_PROMPT envi‐
ronment variable. On systems that use PAM, the custom prompt will also override the prompt specified by a PAM mod‐
ule unless the _p_a_s_s_p_r_o_m_p_t___o_v_e_r_r_i_d_e flag is disabled in _s_u_d_o_e_r_s.
--rr _r_o_l_e, ----rroollee=_r_o_l_e
Run the command with an SELinux security context that includes the specified _r_o_l_e.
--SS, ----ssttddiinn
Write the prompt to the standard error and read the password from the standard input instead of using the terminal
device.
--ss, ----sshheellll
Run the shell specified by the SHELL environment variable if it is set or the shell specified by the invoking user's
password database entry. If a command is specified, it is passed to the shell for execution via the shell's --cc op‐
tion. If no command is specified, an interactive shell is executed. Note that most shells behave differently when
a command is specified as compared to an interactive session; consult the shell's manual for details.
--tt _t_y_p_e, ----ttyyppee=_t_y_p_e
Run the command with an SELinux security context that includes the specified _t_y_p_e. If no _t_y_p_e is specified, the de‐
fault type is derived from the role.
--UU _u_s_e_r, ----ootthheerr--uusseerr=_u_s_e_r
Used in conjunction with the --ll option to list the privileges for _u_s_e_r instead of for the invoking user. The secu‐
rity policy may restrict listing other users' privileges. The _s_u_d_o_e_r_s policy only allows root or a user with the
ALL privilege on the current host to use this option.
--TT _t_i_m_e_o_u_t, ----ccoommmmaanndd--ttiimmeeoouutt=_t_i_m_e_o_u_t
Used to set a timeout for the command. If the timeout expires before the command has exited, the command will be
terminated. The security policy may restrict the ability to set command timeouts. The _s_u_d_o_e_r_s policy requires that
user-specified timeouts be explicitly enabled.
--uu _u_s_e_r, ----uusseerr=_u_s_e_r
Run the command as a user other than the default target user (usually _r_o_o_t). The _u_s_e_r may be either a user name or
a numeric user-ID (UID) prefixed with the ‘#’ character (e.g., #0 for UID 0). When running commands as a UID, many
shells require that the ‘#’ be escaped with a backslash (‘\’). Some security policies may restrict UIDs to those
listed in the password database. The _s_u_d_o_e_r_s policy allows UIDs that are not in the password database as long as
the _t_a_r_g_e_t_p_w option is not set. Other security policies may not support this.
--VV, ----vveerrssiioonn
Print the ssuuddoo version string as well as the version string of the security policy plugin and any I/O plugins. If
the invoking user is already root the --VV option will display the arguments passed to configure when ssuuddoo was built
and plugins may display more verbose information such as default options.
--vv, ----vvaalliiddaattee
Update the user's cached credentials, authenticating the user if necessary. For the _s_u_d_o_e_r_s plugin, this extends
the ssuuddoo timeout for another 15 minutes by default, but does not run a command. Not all security policies support
cached credentials.
---- The ---- option indicates that ssuuddoo should stop processing command line arguments.
Environment variables to be set for the command may also be passed on the command line in the form of _V_A_R=_v_a_l_u_e, e.g.,
LD_LIBRARY_PATH=_/_u_s_r_/_l_o_c_a_l_/_p_k_g_/_l_i_b. Variables passed on the command line are subject to restrictions imposed by the security
policy plugin. The _s_u_d_o_e_r_s policy subjects variables passed on the command line to the same restrictions as normal environment
variables with one important exception. If the _s_e_t_e_n_v option is set in _s_u_d_o_e_r_s, the command to be run has the SETENV tag set or
the command matched is ALL, the user may set variables that would otherwise be forbidden. See sudoers(5) for more information.
CCOOMMMMAANNDD EEXXEECCUUTTIIOONN
When ssuuddoo executes a command, the security policy specifies the execution environment for the command. Typically, the real and
effective user and group and IDs are set to match those of the target user, as specified in the password database, and the group
vector is initialized based on the group database (unless the --PP option was specified).
The following parameters may be specified by security policy:
•• real and effective user-ID
•• real and effective group-ID
•• supplementary group-IDs
•• the environment list
•• current working directory
•• file creation mode mask (umask)
•• SELinux role and type
•• scheduling priority (aka nice value)
PPrroocceessss mmooddeell
There are two distinct ways ssuuddoo can run a command.
If an I/O logging plugin is configured or if the security policy explicitly requests it, a new pseudo-terminal (“pty”) is allo‐
cated and fork(2) is used to create a second ssuuddoo process, referred to as the _m_o_n_i_t_o_r. The _m_o_n_i_t_o_r creates a new terminal ses‐
sion with itself as the leader and the pty as its controlling terminal, calls fork(2), sets up the execution environment as de‐
scribed above, and then uses the execve(2) system call to run the command in the child process. The _m_o_n_i_t_o_r exists to relay job
control signals between the user's existing terminal and the pty the command is being run in. This makes it possible to suspend
and resume the command. Without the monitor, the command would be in what POSIX terms an “orphaned process group” and it would
not receive any job control signals from the kernel. When the command exits or is terminated by a signal, the _m_o_n_i_t_o_r passes
the command's exit status to the main ssuuddoo process and exits. After receiving the command's exit status, the main ssuuddoo passes
the command's exit status to the security policy's close function and exits.
If no pty is used, ssuuddoo calls fork(2), sets up the execution environment as described above, and uses the execve(2) system call
to run the command in the child process. The main ssuuddoo process waits until the command has completed, then passes the command's
exit status to the security policy's close function and exits. As a special case, if the policy plugin does not define a close
function, ssuuddoo will execute the command directly instead of calling fork(2) first. The _s_u_d_o_e_r_s policy plugin will only define a
close function when I/O logging is enabled, a pty is required, or the _p_a_m___s_e_s_s_i_o_n or _p_a_m___s_e_t_c_r_e_d options are enabled. Note that
_p_a_m___s_e_s_s_i_o_n and _p_a_m___s_e_t_c_r_e_d are enabled by default on systems using PAM.
SSiiggnnaall hhaannddlliinngg
When the command is run as a child of the ssuuddoo process, ssuuddoo will relay signals it receives to the command. The SIGINT and
SIGQUIT signals are only relayed when the command is being run in a new pty or when the signal was sent by a user process, not
the kernel. This prevents the command from receiving SIGINT twice each time the user enters control-C. Some signals, such as
SIGSTOP and SIGKILL, cannot be caught and thus will not be relayed to the command. As a general rule, SIGTSTP should be used
instead of SIGSTOP when you wish to suspend a command being run by ssuuddoo.
As a special case, ssuuddoo will not relay signals that were sent by the command it is running. This prevents the command from ac‐
cidentally killing itself. On some systems, the reboot(8) command sends SIGTERM to all non-system processes other than itself
before rebooting the system. This prevents ssuuddoo from relaying the SIGTERM signal it received back to reboot(8), which might
then exit before the system was actually rebooted, leaving it in a half-dead state similar to single user mode. Note, however,
that this check only applies to the command run by ssuuddoo and not any other processes that the command may create. As a result,
running a script that calls reboot(8) or shutdown(8) via ssuuddoo may cause the system to end up in this undefined state unless the
reboot(8) or shutdown(8) are run using the eexxeecc() family of functions instead of ssyysstteemm() (which interposes a shell between the
command and the calling process).
If no I/O logging plugins are loaded and the policy plugin has not defined a cclloossee() function, set a command timeout or required
that the command be run in a new pty, ssuuddoo may execute the command directly instead of running it as a child process.
PPlluuggiinnss
Plugins may be specified via Plugin directives in the sudo.conf(5) file. They may be loaded as dynamic shared objects (on sys‐
tems that support them), or compiled directly into the ssuuddoo binary. If no sudo.conf(5) file is present, or it contains no
Plugin lines, ssuuddoo will use the traditional _s_u_d_o_e_r_s security policy and I/O logging. See the sudo.conf(5) manual for details of
the _/_e_t_c_/_s_u_d_o_._c_o_n_f file and the sudo_plugin(5) manual for more information about the ssuuddoo plugin architecture.
EEXXIITT VVAALLUUEE
Upon successful execution of a command, the exit status from ssuuddoo will be the exit status of the program that was executed. If
the command terminated due to receipt of a signal, ssuuddoo will send itself the same signal that terminated the command.
If the --ll option was specified without a command, ssuuddoo will exit with a value of 0 if the user is allowed to run ssuuddoo and they
authenticated successfully (as required by the security policy). If a command is specified with the --ll option, the exit value
will only be 0 if the command is permitted by the security policy, otherwise it will be 1.
If there is an authentication failure, a configuration/permission problem or if the given command cannot be executed, ssuuddoo exits
with a value of 1. In the latter case, the error string is printed to the standard error. If ssuuddoo cannot stat(2) one or more
entries in the user's PATH, an error is printed to the standard error. (If the directory does not exist or if it is not really
a directory, the entry is ignored and no error is printed.) This should not happen under normal circumstances. The most common
reason for stat(2) to return “permission denied” is if you are running an automounter and one of the directories in your PATH is
on a machine that is currently unreachable.
SSEECCUURRIITTYY NNOOTTEESS
ssuuddoo tries to be safe when executing external commands.
To prevent command spoofing, ssuuddoo checks "." and "" (both denoting current directory) last when searching for a command in the
user's PATH (if one or both are in the PATH). Note, however, that the actual PATH environment variable is _n_o_t modified and is
passed unchanged to the program that ssuuddoo executes.
Users should _n_e_v_e_r be granted ssuuddoo privileges to execute files that are writable by the user or that reside in a directory that
is writable by the user. If the user can modify or replace the command there is no way to limit what additional commands they
can run.
Please note that ssuuddoo will normally only log the command it explicitly runs. If a user runs a command such as sudo su or sudo
sh, subsequent commands run from that shell are not subject to ssuuddoo's security policy. The same is true for commands that offer
shell escapes (including most editors). If I/O logging is enabled, subsequent commands will have their input and/or output
logged, but there will not be traditional logs for those commands. Because of this, care must be taken when giving users access
to commands via ssuuddoo to verify that the command does not inadvertently give the user an effective root shell. For more informa‐
tion, please see the _P_r_e_v_e_n_t_i_n_g _s_h_e_l_l _e_s_c_a_p_e_s section in sudoers(5).
To prevent the disclosure of potentially sensitive information, ssuuddoo disables core dumps by default while it is executing (they
are re-enabled for the command that is run). This historical practice dates from a time when most operating systems allowed
set-user-ID processes to dump core by default. To aid in debugging ssuuddoo crashes, you may wish to re-enable core dumps by set‐
ting “disable_coredump” to false in the sudo.conf(5) file as follows:
Set disable_coredump false
See the sudo.conf(5) manual for more information.
EENNVVIIRROONNMMEENNTT
ssuuddoo utilizes the following environment variables. The security policy has control over the actual content of the command's en‐
vironment.
EDITOR Default editor to use in --ee (sudoedit) mode if neither SUDO_EDITOR nor VISUAL is set.
MAIL Set to the mail spool of the target user when the --ii option is specified or when _e_n_v___r_e_s_e_t is enabled in
_s_u_d_o_e_r_s (unless MAIL is present in the _e_n_v___k_e_e_p list).
HOME Set to the home directory of the target user when the --ii or --HH options are specified, when the --ss option is
specified and _s_e_t___h_o_m_e is set in _s_u_d_o_e_r_s, when _a_l_w_a_y_s___s_e_t___h_o_m_e is enabled in _s_u_d_o_e_r_s, or when _e_n_v___r_e_s_e_t is en‐
abled in _s_u_d_o_e_r_s and _H_O_M_E is not present in the _e_n_v___k_e_e_p list.
LOGNAME Set to the login name of the target user when the --ii option is specified, when the _s_e_t___l_o_g_n_a_m_e option is en‐
abled in _s_u_d_o_e_r_s or when the _e_n_v___r_e_s_e_t option is enabled in _s_u_d_o_e_r_s (unless LOGNAME is present in the _e_n_v___k_e_e_p
list).
PATH May be overridden by the security policy.
SHELL Used to determine shell to run with --ss option.
SUDO_ASKPASS Specifies the path to a helper program used to read the password if no terminal is available or if the --AA op‐
tion is specified.
SUDO_COMMAND Set to the command run by sudo.
SUDO_EDITOR Default editor to use in --ee (sudoedit) mode.
SUDO_GID Set to the group-ID of the user who invoked sudo.
SUDO_PROMPT Used as the default password prompt unless the --pp option was specified.
SUDO_PS1 If set, PS1 will be set to its value for the program being run.
SUDO_UID Set to the user-ID of the user who invoked sudo.
SUDO_USER Set to the login name of the user who invoked sudo.
USER Set to the same value as LOGNAME, described above.
VISUAL Default editor to use in --ee (sudoedit) mode if SUDO_EDITOR is not set.
FFIILLEESS
/etc/sudo.conf ssuuddoo front end configuration
EEXXAAMMPPLLEESS
Note: the following examples assume a properly configured security policy.
To get a file listing of an unreadable directory:
$ sudo ls /usr/local/protected
To list the home directory of user yaz on a machine where the file system holding ~yaz is not exported as root:
$ sudo -u yaz ls ~yaz
To edit the _i_n_d_e_x_._h_t_m_l file as user www:
$ sudoedit -u www ~www/htdocs/index.html
To view system logs only accessible to root and users in the adm group:
$ sudo -g adm more /var/log/syslog
To run an editor as jim with a different primary group:
$ sudoedit -u jim -g audio ~jim/sound.txt
To shut down a machine:
$ sudo shutdown -r +15 "quick reboot"
To make a usage listing of the directories in the /home partition. Note that this runs the commands in a sub-shell to make the
cd and file redirection work.
$ sudo sh -c "cd /home ; du -s * | sort -rn > USAGE"
DDIIAAGGNNOOSSTTIICCSS
Error messages produced by ssuuddoo include:
editing files in a writable directory is not permitted
By default, ssuuddooeeddiitt does not permit editing a file when any of the parent directories are writable by the invoking user.
This avoids a race condition that could allow the user to overwrite an arbitrary file. See the _s_u_d_o_e_d_i_t___c_h_e_c_k_d_i_r option
in sudoers(5) for more information.
editing symbolic links is not permitted
By default, ssuuddooeeddiitt does not follow symbolic links when opening files. See the _s_u_d_o_e_d_i_t___f_o_l_l_o_w option in sudoers(5) for
more information.
effective uid is not 0, is sudo installed setuid root?
ssuuddoo was not run with root privileges. The ssuuddoo binary must be owned by the root user and have the set-user-ID bit set.
Also, it must not be located on a file system mounted with the ‘nosuid’ option or on an NFS file system that maps uid 0 to
an unprivileged uid.
effective uid is not 0, is sudo on a file system with the 'nosuid' option set or an NFS file system without root privileges?
ssuuddoo was not run with root privileges. The ssuuddoo binary has the proper owner and permissions but it still did not run with
root privileges. The most common reason for this is that the file system the ssuuddoo binary is located on is mounted with
the ‘nosuid’ option or it is an NFS file system that maps uid 0 to an unprivileged uid.
fatal error, unable to load plugins
An error occurred while loading or initializing the plugins specified in sudo.conf(5).
invalid environment variable name
One or more environment variable names specified via the --EE option contained an equal sign (‘=’). The arguments to the --EE
option should be environment variable names without an associated value.
no password was provided
When ssuuddoo tried to read the password, it did not receive any characters. This may happen if no terminal is available (or
the --SS option is specified) and the standard input has been redirected from _/_d_e_v_/_n_u_l_l.
a terminal is required to read the password
ssuuddoo needs to read the password but there is no mechanism available for it to do so. A terminal is not present to read
the password from, ssuuddoo has not been configured to read from the standard input, the --SS option was not used, and no
askpass helper has been specified either via the sudo.conf(5) file or the SUDO_ASKPASS environment variable.
no writable temporary directory found
ssuuddooeeddiitt was unable to find a usable temporary directory in which to store its intermediate files.
sudo must be owned by uid 0 and have the setuid bit set
ssuuddoo was not run with root privileges. The ssuuddoo binary does not have the correct owner or permissions. It must be owned
by the root user and have the set-user-ID bit set.
sudoedit is not supported on this platform
It is only possible to run ssuuddooeeddiitt on systems that support setting the effective user-ID.
timed out reading password
The user did not enter a password before the password timeout (5 minutes by default) expired.
you do not exist in the passwd database
Your user-ID does not appear in the system passwd database.
you may not specify environment variables in edit mode
It is only possible to specify environment variables when running a command. When editing a file, the editor is run with
the user's environment unmodified.
SSEEEE AALLSSOO
su(1), stat(2), login_cap(3), passwd(5), sudo.conf(5), sudo_plugin(5), sudoers(5), sudoers_timestamp(5), sudoreplay(8),
visudo(8)
HHIISSTTOORRYY
See the HISTORY file in the ssuuddoo distribution (https://www.sudo.ws/history.html) for a brief history of sudo.
AAUUTTHHOORRSS
Many people have worked on ssuuddoo over the years; this version consists of code written primarily by:
Todd C. Miller
See the CONTRIBUTORS file in the ssuuddoo distribution (https://www.sudo.ws/contributors.html) for an exhaustive list of people who
have contributed to ssuuddoo.
CCAAVVEEAATTSS
There is no easy way to prevent a user from gaining a root shell if that user is allowed to run arbitrary commands via ssuuddoo.
Also, many programs (such as editors) allow the user to run commands via shell escapes, thus avoiding ssuuddoo's checks. However,
on most systems it is possible to prevent shell escapes with the sudoers(5) plugin's _n_o_e_x_e_c functionality.
It is not meaningful to run the cd command directly via sudo, e.g.,
$ sudo cd /usr/local/protected
since when the command exits the parent process (your shell) will still be the same. Please see the _E_X_A_M_P_L_E_S section for more
information.
Running shell scripts via ssuuddoo can expose the same kernel bugs that make set-user-ID shell scripts unsafe on some operating sys‐
tems (if your OS has a /dev/fd/ directory, set-user-ID shell scripts are generally safe).
BBUUGGSS
If you feel you have found a bug in ssuuddoo, please submit a bug report at https://bugzilla.sudo.ws/
SSUUPPPPOORRTT
Limited free support is available via the sudo-users mailing list, see https://www.sudo.ws/mailman/listinfo/sudo-users to sub‐
scribe or search the archives.
DDIISSCCLLAAIIMMEERR
ssuuddoo is provided “AS IS” and any express or implied warranties, including, but not limited to, the implied warranties of mer‐
chantability and fitness for a particular purpose are disclaimed. See the LICENSE file distributed with ssuuddoo or
https://www.sudo.ws/license.html for complete details.
Sudo 1.8.31 October 20, 2019 Sudo 1.8.31