These arguments contain UserRecord structures serialized to JSON,
however only the "secret" part of it, not a whole user record. We do
this since the secret part is conceptually part of the user record and
in some contexts we need a user record in full with both secret and
non-secret part, and in others just the secret and in other just the
non-secret part, but we want to keep this in memory in the same logic.
Hence, let's rename the arguments where we expect a user record
consisting only of the secret part to "secret".
This also makes sure the control buffer is properly aligned. This
matters, as otherwise the control buffer might not be aligned and the
cmsg buffer counting might be off. The incorrect alignment is becoming
visible by using recvmsg_safe() as we suddenly notice the MSG_CTRUNC bit
set because of this.
That said, apparently this isn't enough to make this work on all
kernels. Since I couldn't figure this out, we now add 1K to the buffer
to be sure. We do this once already, also for a pktinfo structure
(though an IPv4/IPv6) one. I am puzzled by this, but this shouldn't
matter much. it works locally just fine, except for those ubuntu CI
kernels...
While we are at it, make some other changes too, to simplify and
modernize the function.
Previously pam_systemd_home.so was relying on `PAM_PROMPT_ECHO_OFF` to
display error messages to the user and also display the next prompt.
`PAM_PROMPT_ECHO_OFF` was never meant as a way to convey information to
the user, and following the example set in pam_unix.so you can see that
it's meant to _only_ display the prompt. Details about why the
authentication failed should be done in a `PAM_ERROR_MSG` before
displaying a short prompt as per usual using `PAM_PROMPT_ECHO_OFF`.
[127/1355] Compiling C object 'src/shared/5afaae1@@systemd-shared-245@sta/ethtool-util.c.o'
../src/shared/ethtool-util.c: In function ‘ethtool_get_permanent_macaddr’:
../src/shared/ethtool-util.c:260:60: warning: array subscript 5 is outside the bounds of an interior zero-length array ‘__u8[0]’ {aka ‘unsigned char[]’} [-Wzero-length-bounds]
260 | ret->ether_addr_octet[i] = epaddr.addr.data[i];
| ~~~~~~~~~~~~~~~~^~~
In file included from ../src/shared/ethtool-util.c:5:
../src/shared/linux/ethtool.h:704:7: note: while referencing ‘data’
704 | __u8 data[0];
| ^~~~
../src/shared/ethtool-util.c: In function ‘ethtool_set_features’:
../src/shared/ethtool-util.c:488:31: warning: array subscript 0 is outside the bounds of an interior zero-length array ‘__u32[0]’ {aka ‘unsigned int[]’} [-Wzero-length-bounds]
488 | len = buffer.info.data[0];
| ~~~~~~~~~~~~~~~~^~~
In file included from ../src/shared/ethtool-util.c:5:
../src/shared/linux/ethtool.h:631:8: note: while referencing ‘data’
631 | __u32 data[0];
| ^~~~
The kernel should not define the length of the array, but it does. We can't fix
that, so let's use a cast to avoid the warning.
For https://github.com/systemd/systemd/issues/6119#issuecomment-626073743.
v2:
- use #pragma instead of a cast. It seems the cast only works in some cases, and
gcc is "smart" enough to see beyond the cast. Unfortunately clang does not support
this warning, so we need to do a config check whether to try to suppress.
Fixes: #15757
(Note there's quite some confusion regarding "exit status" vs. "exit
code" in the docs here. We should clean this up fully one day. This
change tries to fix some occasions of the wrong use, but not all.)
I was looking for the explanation for the exclamation mark in the text,
and couldn't find it, searching for "!". Let's make this easier, and
indicate the character meant.
kernel 5.6 added support for a new flag for getrandom(): GRND_INSECURE.
If we set it we can get some random data out of the kernel random pool,
even if it is not yet initializated. This is great for us to initialize
hash table seeds and such, where it is OK if they are crap initially. We
used RDRAND for these cases so far, but RDRAND is only available on
newer CPUs and some archs. Let's now use GRND_INSECURE for these cases
as well, which means we won't needlessly delay boot anymore even on
archs/CPUs that do not have RDRAND.
Of course we never set this flag when generating crypto keys or uuids.
Which makes it different from RDRAND for us (and is the reason I think
we should keep explicit RDRAND support in): RDRAND we don't trust enough
for crypto keys. But we do trust it enough for UUIDs.
Apart from running CIFuzz for each relevant PR, let's run it
unconditionally for each push to master to detect possible issues
(caused by ignored PRs, etc.).
Followup to 94f660a8fe.
Commit 3d864658ea ("hwdb: assume all Medion Akoya E-models have the
same matrix"), unified the entries for most Medion Akoya E* modes,
including the entry for the Medion Akoya E2215T MD60198.
But the accelerometer on the E2215T has an ACPI-id of KIOX000A, rather
then KIOX010A as the other models have, so that commit broke the
ACCEL_MOUNT_MATRIX for the E2215T.
Add a separate match for the E2215T so that it gets the correct
ACCEL_MOUNT_MATRIX again.
Let's make the logic a bit smarter: if we detect that /home is
encrypted, let's avoid double encryption and prefer plain
directory/subvolumes instead of our regular luks images.
Also, allow configuration go storage/file system via an env var passed
to homework. In a later commit, let's then change homed to initialize
that env var from a config file setting, when invoking homework.
Make use of the new user_record_build_image_path() helper the previous
commit added to share some code.
Also, let's make sure we update all parsed-out fields with the new data
from the binding, so that the parsed-out fields are definitely
up-to-date.
Lennart Poettering