Comment by ebiggers
10 hours ago
It doesn't seem to actually get used that way in practice. ALG_SET_KEY_BY_KEY_SERIAL didn't even appear until just a few years ago. And either way, if the interface allows you to overwrite the su binary, whether it theoretically could provide some other security benefit becomes kind of irrelevant.
It is being used that way:
https://github.com/opensourcerouting/frr/blob/2b48e4f97fb021...
And, sure, if it breaks system security it's pointless. But so did "dirty pipe".
I do agree the number of issues in AF_ALG is annoying, which is why I suggested a CAP_* restriction. Maybe CAP_SYS_ADMIN in init_ns, that's kinda the big hammer.