Add tests for {get/set}auid, {get/set}audit, {get/set}audit_addr

[aniketp]

Summary

This revision introduces tests for syscalls from audit class administrative.
The syscalls are:

• setauid(2)
• getauid(2)
• setaudit(2)
• getaudit(2)
• setaudit_addr(2)
• getaudit_addr(2)

Test Plan

Execute make && make install from test/sys/audit.
Execute kyua test from /usr/tests/sys/audit. All testcases should succeed.

[asomers]

tests/sys/audit/administrative.c

409 ↗

(On Diff #43967)

In new code, you should prefer to use standardized types like unsigned int or uint32_t instead of u_int. And why use malloc for just 32 bits?

414 ↗

(On Diff #43967)

You're passing uninitialized memory here. I'm not sure exactly how this system call is supposed to be used, but I would guess that you should supply sizeof(auditinfo).

464 ↗

(On Diff #43967)

Don't forget to fix the uninitialized memory error here, too.

[aniketp]

Instead of passing allocated and unitialized memory as the length for {get/set}audit_addr, simply pass the sizeof(auditinfo) as it is supposed to be used.

Thanks to @asomers for suggesting. Although I wish the man-page was a bit more clear on
this regard (about what exactly is length).

[asomers]

In D15871#335722, @aniketp wrote:

Instead of passing allocated and unitialized memory as the length for {get/set}audit_addr, simply pass the sizeof(auditinfo) as it is supposed to be used.

Thanks to @asomers for suggesting. Although I wish the man-page was a bit more clear on
this regard (about what exactly is length).

Though it doesn't say so explicitly, length's purpose is probably to allow the auditinfo_addr structure to grow in the future, while preserving the ability of older programs to continue using the old structure. It's a simpler alternative to updating the syscall.