Re: ASAN and dhcpcd with privilege separation

[Roy Marples <roy%marples.name@localhost>]

On 31/01/2021 14:10, Kamil Rytarowski wrote:
> On 31.01.2021 13:21, Roy Marples wrote:
> > What I want to end up with is some #ifdef SANITIZE foo so that enough is
> > disabled to make it work.
>
> You can use something like this:
>
> #ifndef __has_feature
> #define __has_feature(x)        0
> #endif
>
> #if __has_feature(address_sanitizer) || \
>      defined(__SANITIZE_ADDRESS__) || \
>      __has_feature(leak_sanitizer) || \
>      defined(__SANITIZE_LEAK__)
>
> asan_lsan_code_here();
>
> #else
>
> no_asan_lsan_code_here();
>
> #endif

Yes, but I don't know what to disable *in dhcpcd* other than the whole privsep 
code, which is what really needs testing!

I was hoping I could just disable dropping user, chroot and any platform 
sandboxing but if the sanitizers stop working when a process forks it's pretty 
useless at this point to continue.

Now if the expectation is that the sanitizers are supposed to work with 
socketpair, forking and moving data across the sockets to each other I'd love to 
know why it's not working for dhcpcd with the patches I posted previously.

Roy