This prevents visudo from creating a new zero-length sudoers file
if the user exited the editor without making any changes. Files
created via a @include directive are preserved, even if empty, to
avoid a parse error. GitHub issue #294.
The format value has to be a string literal, every time.
Otherwise, you are not using these functions correctly. To reinforce this fact, I putrestrict over every non-contrib example of this I could find.
The command is now always run in its own process group. If visudo
is run in the foreground, the command is run in the foreground too.
Otherwise, run the command in the background. There is a race
between the tcsetpgrp() call in the parent and the execve() in the
child. If we lose the race and the command needs the controlling
terminal, it will be stopped with SIGTTOU or SIGTTIN, which the
waitpid() loop will handle.
Since visudo doesn't alter the terminal settings it is possible for
the terminal to have the ONLCR bit set in the output control flags.
In that case, we will get a CR, not a NL when the user presses
enter/return. One way this can happen is if visudo is run in the
background from a shell that supports line editing and the editor
restores the (cbreak-style) terminal mode when it finishes.
We just need a way for the policy (and visudo) to override the
default sudoers path. This adds a getter to be used in file.c when
sudoers is first opened.
When adminconfdir is enabled, the destination pathh may be different
from the path we opened. We always store an edited file in the
adminconfdir (if enabled). This makes it possible to use visudo
when /etc/sudoers is located on a read-only file system.
Otherwise, visudo will get SIGTTOU if it tries to write to the
terminal after the editor finishes. Also avoid races by setting
the process group ID in both the parent and child, and grant the
controlling terminal in the parent, not the child.
We use "--" to separate the editor and arguments from the files to edit.
If the editor arguments include "--", sudo can be tricked into allowing
the user to edit a file not permitted by the security policy.
Thanks to Matthieu Barjole and Victor Cutillas of Synacktiv
(https://synacktiv.com) for finding this bug.
Renamed __malloc -> sudo_malloclike, __printflike -> sudo_printflike,
__printf0like -> sudo_printf0like.
Add sudo_noreturn instead of __attribute__((__noreturn__)).
We do not use stdnoreturn.h since it has been deprecated in C23
in favor of the [[noreturn]] attribute.
We don't check the owner or permissions on a sudoers file that is
specified as an argument to visudo by default. However, the owner
and mode of files included via @includedir were still checked. This
commit makes the owner and permissions checks for filed included
via @includedir follow the same as for the original sudoers file.
The hook can be used to log parser errors (sudoers module) or keep
track of which files have an error (visudo).
Previously, we only kept track of a single parse error.
There is no case where we should fail to find an editor just because
the values of EDITOR, VISUAL and SUDO_EDITOR are unavailable. Both
sudoedit and the "env_editor" sudoers setting are documented as
falling back on the hard-coded list of editors in the "editors"
sudoers setting. Bug #1000
