> The bug is caused by an error check that filters out garbage sent to PID 1. The check works correctly, except that the resulting action is a too harsh: instead of complaining and dropping it will abort the process.
* https://www.reddit.com/r/linux/comments/54yfcd/how_to_crash_...
In fact, the opposite was the case. The root of the problem was identified in the GitHub bug report:
* https://github.com/systemd/systemd/issues/4234#issuecomment-...
* hhttps://github.com/systemd/systemd/commit/d875aa8ce10b458dc2...
What happened was that Lennart Poettering removed an error check that filtered out zero-length messages. This left the flow of control to fall through to a later point where an assertion, that had been earlier added by Lennart Poettering with the assumption that this check for zero was in place (as it had been at the time), then triggered.
Of course, no-one that I have seen has yet asked why "" as a command-line argument to systemd-notify results in a zero-length message in the first place. After all, according to the doco that would be length 1, a single terminating LF byte, not zero length. That said, the server still should be proof against zero-length network input.