Comment by Denvercoder9

3 years ago

I see your point, but suggesting adding an additional library dependency while we're discussing a supply chain attack is quite ironic.

Should've said function call not library call. My bad. Basically if you already have the linux/landlock.h, that should provide everything you need to do without explicit references to SYS...

  • Now we are running in circles. As you see in the git commit, the compile check was added because the existance of linux/landlock.h alone was not enough to check that the feature can be used.

    This header defines the data types for the Linux kernel interface, but not how the syscall landlock_create_ruleset(2) will be issued. That is provided by libc either as a separate wrapper function (does not exist in glibc) or the implementation needs to use syscall(SYS_landlock_create_ruleset, ...), with the constant also being provided by libc. That is how it works for all syscalls and you won't be able to change this.

    • The only source of the claim that the existence of.linux/landlock.h is insufficient is (AFAICT) the malicious git commit. Why trust the comment, written by the attacker, to explain away a malicious change?

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