sudo(8) — Linux manual page

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SUDO(8)                BSD System Manager's Manual               SUDO(8)

NAME         top

     sudo, sudoedit — execute a command as another user

SYNOPSIS         top

     sudo -h | -K | -k | -V
     sudo -v [-ABknS] [-g group] [-h host] [-p prompt] [-u user]
     sudo -l [-ABknS] [-g group] [-h host] [-p prompt] [-U user]
          [-u user] [command]
     sudo [-ABbEHnPS] [-C num] [-D directory] [-g group] [-h host]
          [-p prompt] [-R directory] [-T timeout] [-u user] [VAR=value]
          [-i | -s] [command]
     sudoedit [-ABknS] [-C num] [-D directory] [-g group] [-h host]
          [-p prompt] [-R directory] [-T timeout] [-u user] file ...

DESCRIPTION         top

     sudo allows a permitted user to execute a command as the superuser
     or another user, as specified by the security policy.  The invoking
     user's real (not effective) user-ID is used to determine the user
     name with which to query the security policy.

     sudo 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 sudo front end.  The default security policy is sudoers, which
     is configured via the file /etc/sudoers, or via LDAP.  See the
     Plugins section for more information.

     The security policy determines what privileges, if any, a user has
     to run sudo.  The policy may require that users authenticate
     themselves with a password or another authentication mechanism.  If
     authentication is required, sudo 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
     sudoers security policy is 5 minutes.

     Security policies may support credential caching to allow the user
     to run sudo again for a period of time without requiring
     authentication.  By default, the sudoers policy caches credentials
     on a per-terminal basis for 5 minutes.  See the timestamp_type and
     timestamp_timeout options in sudoers(5) for more information.  By
     running sudo with the -v option, a user can update the cached
     credentials without running a command.

     On systems where sudo is the primary method of gaining superuser
     privileges, it is imperative to avoid syntax errors in the security
     policy configuration files.  For the default security policy,
     sudoers(5), changes to the configuration files should be made using
     the visudo(8) utility which will ensure that no syntax errors are
     introduced.

     When invoked as sudoedit, the -e option (described below), is
     implied.

     Security policies may log successful and failed attempts to use
     sudo.  If an I/O plugin is configured, the running command's input
     and output may be logged as well.

     The options are as follows:

     -A, --askpass
                 Normally, if sudo requires a password, it will read it
                 from the user's terminal.  If the -A (askpass) 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, sudo will exit with
                 an error.

     -B, --bell  Ring the bell as part of the password prompt when a
                 terminal is present.  This option has no effect if an
                 askpass program is used.

     -b, --background
                 Run the given command in the background.  Note that it
                 is not possible to use shell job control to manipulate
                 background processes started by sudo.  Most interactive
                 commands will fail to work properly in background mode.

     -C num, --close-from=num
                 Close all file descriptors greater than or equal to num
                 before executing a command.  Values less than three are
                 not permitted.  By default, sudo 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 sudoers policy only permits use
                 of the -C option when the administrator has enabled the
                 closefrom_override option.

     -D directory, --chdir=directory
                 Run the command in the specified directory instead of
                 the current working directory.  The security policy may
                 return an error if the user does not have permission to
                 specify the working directory.

     -E, --preserve-env
                 Indicates to the security policy that the user wishes
                 to preserve their existing environment variables.  The
                 security policy may return an error if the user does
                 not have permission to preserve the environment.

     --preserve-env=list
                 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 permission to preserve the
                 environment.  This option may be specified multiple
                 times.

     -e, --edit  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 sudoers 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 editor 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 sudo,
                 the editor is run with the invoking user's environment
                 unmodified.  If the temporary file becomes empty after
                 editing, the user will be prompted before it is
                 installed.  If, for some reason, sudo 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.

     -g group, --group=group
                 Run the command with the primary group set to group
                 instead of the primary group specified by the target
                 user's password database entry.  The group 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
                 -u option is specified, the command will be run as the
                 invoking user.  In either case, the primary group will
                 be set to group.  The sudoers policy permits any of the
                 target user's groups to be specified via the -g option
                 as long as the -P option is not in use.

     -H, --set-home
                 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.

     -h, --help  Display a short help message to the standard output and
                 exit.

     -h host, --host=host
                 Run the command on the specified host if the security
                 policy plugin supports remote commands.  Note that the
                 sudoers plugin does not currently support running
                 remote commands.  This may also be used in conjunction
                 with the -l option to list a user's privileges for the
                 remote host.

     -i, --login
                 Run the shell specified by the target user's password
                 database entry as a login shell.  This means that
                 login-specific resource files such as .profile,
                 .bash_profile or .login will be read by the shell.  If
                 a command is specified, it is passed to the shell for
                 execution via the shell's -c option.  If no command is
                 specified, an interactive shell is executed.  sudo
                 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
                 Command environment section in the sudoers(5) manual
                 documents how the -i option affects the environment in
                 which a command is run when the sudoers policy is in
                 use.

     -K, --remove-timestamp
                 Similar to the -k option, except that it removes the
                 user's cached credentials entirely and may not be used
                 in conjunction with a command or other option.  This
                 option does not require a password.  Not all security
                 policies support credential caching.

     -k, --reset-timestamp
                 When used without a command, invalidates the user's
                 cached credentials.  In other words, the next time sudo
                 is run a password will be required.  This option does
                 not require a password and was added to allow a user to
                 revoke sudo permissions from a .logout file.

                 When used in conjunction with a command or an option
                 that may require a password, this option will cause
                 sudo to ignore the user's cached credentials.  As a
                 result, sudo will prompt for a password (if one is
                 required by the security policy) and will not update
                 the user's cached credentials.

                 Not all security policies support credential caching.

     -l, --list  If no command is specified, list the allowed (and
                 forbidden) commands for the invoking user (or the user
                 specified by the -U 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 command is specified and is permitted by the
                 security policy, the fully-qualified path to the
                 command is displayed along with any command line
                 arguments.  If a command is specified but not allowed
                 by the policy, sudo will exit with a status value of 1.

     -n, --non-interactive
                 Avoid prompting the user for input of any kind.  If a
                 password is required for the command to run, sudo will
                 display an error message and exit.

     -P, --preserve-groups
                 Preserve the invoking user's group vector unaltered.
                 By default, the sudoers policy will initialize the
                 group vector 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.

     -p prompt, --prompt=prompt
                 Use a custom password prompt with optional escape
                 sequences.  The following percent (‘%’) escape
                 sequences are supported by the sudoers policy:

                 %H  expanded to the host name including the domain name
                     (on if the machine's host name is fully qualified
                     or the fqdn 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 rootpw, targetpw, and
                     runaspw flags in sudoers(5))

                 %U  expanded to the login name of the user the command
                     will be run as (defaults to root unless the -u
                     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 environment variable.  On systems that use
                 PAM, the custom prompt will also override the prompt
                 specified by a PAM module unless the
                 passprompt_override flag is disabled in sudoers.

     -R directory, --chroot=directory
                 Change to the specified root directory (see chroot(8))
                 before running the command.  The security policy may
                 return an error if the user does not have permission to
                 specify the root directory.

     -S, --stdin
                 Write the prompt to the standard error and read the
                 password from the standard input instead of using the
                 terminal device.

     -s, --shell
                 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 -c option.  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.

     -U user, --other-user=user
                 Used in conjunction with the -l option to list the
                 privileges for user instead of for the invoking user.
                 The security policy may restrict listing other users'
                 privileges.  The sudoers policy only allows root or a
                 user with the ALL privilege on the current host to use
                 this option.

     -T timeout, --command-timeout=timeout
                 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 sudoers policy
                 requires that user-specified timeouts be explicitly
                 enabled.

     -u user, --user=user
                 Run the command as a user other than the default target
                 user (usually root).  The user 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 sudoers policy allows UIDs that are not in the
                 password database as long as the targetpw option is not
                 set.  Other security policies may not support this.

     -V, --version
                 Print the sudo 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 -V
                 option will display the arguments passed to configure
                 when sudo was built and plugins may display more
                 verbose information such as default options.

     -v, --validate
                 Update the user's cached credentials, authenticating
                 the user if necessary.  For the sudoers plugin, this
                 extends the sudo timeout for another 5 minutes by
                 default, but does not run a command.  Not all security
                 policies support cached credentials.

     --          The -- option indicates that sudo should stop
                 processing command line arguments.

     Options that take a value may only be specified once unless
     otherwise indicated in the description.  This is to help guard
     against problems caused by poorly written scripts that invoke sudo
     with user-controlled input.

     Environment variables to be set for the command may also be passed
     on the command line in the form of VAR=value, e.g.,
     LD_LIBRARY_PATH=/usr/local/pkg/lib.  Variables passed on the
     command line are subject to restrictions imposed by the security
     policy plugin.  The sudoers policy subjects variables passed on the
     command line to the same restrictions as normal environment
     variables with one important exception.  If the setenv option is
     set in sudoers, 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.

COMMAND EXECUTION         top

     When sudo 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 -P
     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)

     scheduling priority (aka nice value)

   Process model
     There are two distinct ways sudo 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 allocated
     and fork(2) is used to create a second sudo process, referred to as
     the monitor.  The monitor creates a new terminal session with
     itself as the leader and the pty as its controlling terminal, calls
     fork(2), sets up the execution environment as described above, and
     then uses the execve(2) system call to run the command in the child
     process.  The monitor 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 monitor passes the command's exit status to the
     main sudo process and exits.  After receiving the command's exit
     status, the main sudo passes the command's exit status to the
     security policy's close function and exits.

     If no pty is used, sudo 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 sudo 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, sudo will execute the command directly instead of calling
     fork(2) first.  The sudoers policy plugin will only define a close
     function when I/O logging is enabled, a pty is required, or the
     pam_session or pam_setcred options are enabled.  Note that
     pam_session and pam_setcred are enabled by default on systems using
     PAM.

     On systems that use PAM, the security policy's close function is
     responsible for closing the PAM session.  It may also log the
     command's exit status.

   Signal handling
     When the command is run as a child of the sudo process, sudo 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 sudo.

     As a special case, sudo will not relay signals that were sent by
     the command it is running.  This prevents the command from
     accidentally 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 sudo 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 sudo and not any other processes
     that the command may create.  As a result, running a script that
     calls reboot(8) or shutdown(8) via sudo may cause the system to end
     up in this undefined state unless the reboot(8) or shutdown(8) are
     run using the exec() family of functions instead of system() (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 close() function, set a command timeout or required that
     the command be run in a new pty, sudo may execute the command
     directly instead of running it as a child process.

   Plugins
     Plugins may be specified via Plugin directives in the sudo.conf(5)
     file.  They may be loaded as dynamic shared objects (on systems
     that support them), or compiled directly into the sudo binary.  If
     no sudo.conf(5) file is present, or if it doesn't contain any
     Plugin lines, sudo will use sudoers(5) for the policy, auditing and
     I/O logging plugins.  See the sudo.conf(5) manual for details of
     the /etc/sudo.conf file and the sudo_plugin(5) manual for more
     information about the sudo plugin architecture.

EXIT VALUE         top

     Upon successful execution of a command, the exit status from sudo
     will be the exit status of the program that was executed.  If the
     command terminated due to receipt of a signal, sudo will send
     itself the same signal that terminated the command.

     If the -l option was specified without a command, sudo will exit
     with a value of 0 if the user is allowed to run sudo and they
     authenticated successfully (as required by the security policy).
     If a command is specified with the -l 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, sudo exits with
     a value of 1.  In the latter case, the error string is printed to
     the standard error.  If sudo 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.

SECURITY NOTES         top

     sudo tries to be safe when executing external commands.

     To prevent command spoofing, sudo 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 not modified and is passed
     unchanged to the program that sudo executes.

     Users should never be granted sudo 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 sudo 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
     sudo'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
     sudo to verify that the command does not inadvertently give the
     user an effective root shell.  For more information, please see the
     Preventing shell escapes section in sudoers(5).

     To prevent the disclosure of potentially sensitive information,
     sudo 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 sudo
     crashes, you may wish to re-enable core dumps by setting
     “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.

ENVIRONMENT         top

     sudo utilizes the following environment variables.  The security
     policy has control over the actual content of the command's
     environment.

     EDITOR           Default editor to use in -e (sudoedit) mode if
                      neither SUDO_EDITOR nor VISUAL is set.

     MAIL             Set to the mail spool of the target user when the
                      -i option is specified or when env_reset is
                      enabled in sudoers (unless MAIL is present in the
                      env_keep list).

     HOME             Set to the home directory of the target user when
                      the -i or -H options are specified, when the -s
                      option is specified and set_home is set in
                      sudoers, when always_set_home is enabled in
                      sudoers, or when env_reset is enabled in sudoers
                      and HOME is not present in the env_keep list.

     LOGNAME          Set to the login name of the target user when the
                      -i option is specified, when the set_logname
                      option is enabled in sudoers or when the env_reset
                      option is enabled in sudoers (unless LOGNAME is
                      present in the env_keep list).

     PATH             May be overridden by the security policy.

     SHELL            Used to determine shell to run with -s option.

     SUDO_ASKPASS     Specifies the path to a helper program used to
                      read the password if no terminal is available or
                      if the -A option is specified.

     SUDO_COMMAND     Set to the command run by sudo, including command
                      line arguments.  The command line arguments are
                      truncated at 4096 characters to prevent a
                      potential execution error.

     SUDO_EDITOR      Default editor to use in -e (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 -p
                      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 -e (sudoedit) mode if
                      SUDO_EDITOR is not set.

FILES         top

     /etc/sudo.conf            sudo front end configuration

EXAMPLES         top

     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 index.html 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"

DIAGNOSTICS         top

     Error messages produced by sudo include:

     editing files in a writable directory is not permitted
           By default, sudoedit 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 sudoedit_checkdir
           option in sudoers(5) for more information.

     editing symbolic links is not permitted
           By default, sudoedit does not follow symbolic links when
           opening files.  See the sudoedit_follow option in sudoers(5)
           for more information.

     effective uid is not 0, is sudo installed setuid root?
           sudo was not run with root privileges.  The sudo 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?
           sudo was not run with root privileges.  The sudo 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 sudo 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 -E
           option contained an equal sign (‘=’).  The arguments to the
           -E option should be environment variable names without an
           associated value.

     no password was provided
           When sudo tried to read the password, it did not receive any
           characters.  This may happen if no terminal is available (or
           the -S option is specified) and the standard input has been
           redirected from /dev/null.

     a terminal is required to read the password
           sudo 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, sudo has not been configured to read from
           the standard input, the -S 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
           sudoedit 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
           sudo was not run with root privileges.  The sudo 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 sudoedit 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.

SEE ALSO         top

     su(1), stat(2), login_cap(3), passwd(5), sudo.conf(5),
     sudo_plugin(5), sudoers(5), sudoers_timestamp(5), sudoreplay(8),
     visudo(8)

HISTORY         top

     See the HISTORY file in the sudo distribution
     (https://www.sudo.ws/history.html) for a brief history of sudo.

AUTHORS         top

     Many people have worked on sudo over the years; this version
     consists of code written primarily by:

           Todd C. Miller

     See the CONTRIBUTORS file in the sudo distribution
     (https://www.sudo.ws/contributors.html) for an exhaustive list of
     people who have contributed to sudo.

CAVEATS         top

     There is no easy way to prevent a user from gaining a root shell if
     that user is allowed to run arbitrary commands via sudo.  Also,
     many programs (such as editors) allow the user to run commands via
     shell escapes, thus avoiding sudo's checks.  However, on most
     systems it is possible to prevent shell escapes with the sudoers(5)
     plugin's noexec 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 EXAMPLES section for more
     information.

     Running shell scripts via sudo can expose the same kernel bugs that
     make set-user-ID shell scripts unsafe on some operating systems (if
     your OS has a /dev/fd/ directory, set-user-ID shell scripts are
     generally safe).

BUGS         top

     If you feel you have found a bug in sudo, please submit a bug
     report at https://bugzilla.sudo.ws/

SUPPORT         top

     Limited free support is available via the sudo-users mailing list,
     see https://www.sudo.ws/mailman/listinfo/sudo-users to subscribe or
     search the archives.

DISCLAIMER         top

     sudo is provided “AS IS” and any express or implied warranties,
     including, but not limited to, the implied warranties of
     merchantability and fitness for a particular purpose are
     disclaimed.  See the LICENSE file distributed with sudo or
     https://www.sudo.ws/license.html for complete details.

COLOPHON         top

     This page is part of the sudo (execute a command as another user)
     project.  Information about the project can be found at
     https://www.sudo.ws/.  If you have a bug report for this manual
     page, see ⟨https://bugzilla.sudo.ws/⟩.  This page was obtained from
     the project's upstream Git repository
     ⟨https://github.com/sudo-project/sudo⟩ on 2021-04-01.  (At that
     time, the date of the most recent commit that was found in the
     repository was 2021-03-31.)  If you discover any rendering problems
     in this HTML version of the page, or you believe there is a better
     or more up-to-date source for the page, or you have corrections or
     improvements to the information in this COLOPHON (which is not part
     of the original manual page), send a mail to man-pages@man7.org

Sudo 1.9.6p1                September 1, 2020               Sudo 1.9.6p1

Pages that refer to this page: homectl(1)journalctl(1)localectl(1)loginctl(1)machinectl(1)portablectl(1)setpriv(1)systemctl(1)systemd(1)systemd-analyze(1)systemd-ask-password(1)systemd-inhibit(1)systemd-nspawn(1)timedatectl(1)userdbctl(1)nsswitch.conf(5)credentials(7)systemd-tmpfiles(8)