This will make things a bit longer for now, but more powerful as we can
reuse the userns fd between calls to remount_idmap() if we need to
adjust multiple mounts.
No change in behaviour, just some minor refactoring.
I guess it was only a question of time until we need to add the final
frontier of notification functions: one that combines the features of
all the others:
1. specifiying a source PID
2. taking a list of fds to send along
3. accepting a format string for the status string
Hence, let's add it.
When pam_end() is called after a fork, and it cleans up caches, it sets
PAM_DATA_SILENT in error_status. FDs will be shared with the parent, so
we do not want to attempt to close them from a child process, or we'll
hit assertions. Complain loudly and skip.
it's a bit confusing that on 32bit systems we'd risk session IDs
overruns like this. Let's expose the same behaviour everywhere and stick
to 64bit ids.
Since we format the ids as strings anyway this doesn't really change
anything performance-wise, it just pushes out collisions by overrun to
basically never happen.
sd-event objects use hashmaps, which use module-global state, so it is not safe
to pass a sd-event object created by a module instance to another module instance
(e.g.: when two libraries static linking sd-event are pulled in a single process).
Initialize a random per-module origin id and store it in the object, and compare
it when entering a public API, and error out if they don't match, together with
the PID.
sd-journal objects use hashmaps, which use module-global state, so it is not safe
to pass a sd-journal object created by a module instance to another module instance
(e.g.: when two libraries static linking sd-journal are pulled in a single process).
Initialize a random per-module origin id and store it in the object, and compare
it when entering a public API, and error out if they don't match, together with
the PID.
sd-bus objects use hashmaps, which use module-global state, so it is not safe
to pass a sd-bus object created by a module instance to another module instance
(e.g.: when two libraries static linking sd-bus are pulled in a single process).
Initialize a random per-module origin id and store it in the object, and compare
it when entering a public API, and error out if they don't match, together with
the PID.
crypsetup-fido2 always depended on both libfido2 and libcryptsetup, but
0a8e026e82 forgot to make the then
implicit dependency on libcryptsetup explicit when moving it from
cryptsetup/ to shared/. This breaks builds when libfido2 is autodetected
but the system is missing libcryptsetup.
Introduce an explicit check for HAVE_LIBCRYPTSETUP such that
cryptsetup-fido2 is only built when both libraries are available.
Fixes#27374.
If we try to close after a fork, the FDs will have been cloned
too and we'll assert. This can happen for example in PAM modules.
Avoid the macro and define ref/unref by hand to do the same check.
This doesn't really matter too much as both are static functions. But
it's confusing as hell both when debugging and reading code, given that
homed actually uses mount-util.c
Hence, let's just rename one of the two, to minimize confusion.
No actual change in behaviour.
(and sooner or later we might want to export mount-util.c's version of
the function, since it's generically useful)
When we're checking if /etc/resolv.conf exists so we can bind mount
on top of it, we care about whether the symlink itself exists if
/etc/resolv.conf exists and not the file it points to, so add
CHASE_NOFOLLOW to make sure we check existence of the symlink and
not the file it points to.
sd-bus connection is cached by the two pam modules globally, but this
can lead to issues due to hashmaps (used by sd-bus) using a global
static variable for the shared hash key, which is different per module
as both modules are loaded in the same process.
This happens because the sd-bus object is create in one module, but
used in the other, so global state does not match.
Use a different pam cache identifier for the sd-bus pointer, so that
each module uses a different sd-bus connection as a workaround.
Fixes https://github.com/systemd/systemd/issues/27216
Fixes https://github.com/systemd/systemd/issues/17266
acquire_home() takes a reference to a sd-bus object, which the open_session
hook cleans on success. But only when handling a user actually owned by homed,
it did not clean it up when skipping because it is being invoked on a system
user.
We need to be careful with sd-bus here as pam_sm_open_session is the last
hook before forking, and we want to clean up sd-bus before that happens, or
we'll have a broken reference (FDs are cloexec) in the child process, which
will then assert when attempting to close them, or leak the bus connection
which causes dbus to complain loudly:
dbus-daemon[62]: [system] Connection has not authenticated soon enough, closing it (auth_timeout=30000ms, elapsed: 30020ms)
Yu Watanabe
Luca Boccassi
Frantisek Sumsal
Eric CurtinandRichard Hughes
Lennart Poettering
Vitaly Kuznetsov
Lawrence Thorpe
Thorsten Kukuk
Daan De Meyer
Wolfgang Müller
Zbigniew Jędrzejewski-Szmek
David Tardon