Re: [syzbot] [mptcp?] KMSAN: uninit-value in mptcp_established_options

[Alexander Potapenko]

> >>>> Plus I'm not exactly sure to understand the issue here: mp_opt is
> >>>> defined and used only in mptcp_incoming_options(), and I don't see
> >>>> anything using it after the end of this function. Or did I miss something?
> >>>
> >>> I also had hard time understanding the backtrace, I think some frames
> >>> are omitted/missing (it happens sometime, IDK why), specifically the one
> >>> related to mptcp_options_received() - which would be useful to
> >>> understand the issue.
> >>
> >> This is probably related to
> >> https://lore.kernel.org/all/69e7ee1f.a00a0220.17a17.001d.GAE@xxxxxxxxxx/T/
> >
> > Ah yes, it looks similar.
> >
> >> Let me send the patch, perhaps this issue will also go away.
> >
> > That would be great, thank you!
>
> Thank you for having sent your patch.
>
> Here is one combining your modifications, and the ones from Paolo, for
> syzbot. If this one is OK, we can continue with Paolo's patch.


Hi Matt,

Unfortunately my approach was wrong: see tglx's response there.
Hope we'll figure something out (__no_kmsan_checks looks promising)

Alex