Re: net/sctp: use-after-free in __sctp_connect

From: Marcelo Ricardo Leitner
Date: Wed Jan 13 2016 - 20:45:57 EST


Em 13-01-2016 23:37, YUAN Jia escreveu:
> Hi Dmitry,
>
> I've tested your program, but found nothing happens. So, I suspect it may cause kernel crash only on some special kernel version?
> I was just using kernel of 4.2.3. What about you?
>
> Richard

Please don't top-post.

Note that it doesn't necessarily crashes the system. syzkaller is using kasan to detect such type of invalid accesses, which in some conditions may lead to crashes, weird behavior or just nothing at all. It all depends on how much the memory was already changed after it was freed.

> -----Original Message-----
> From: linux-sctp-owner@xxxxxxxxxxxxxxx [mailto:linux-sctp-owner@xxxxxxxxxxxxxxx] On Behalf Of Dmitry Vyukov
> Sent: 2016å1æ13æ 17:53
> To: Vlad Yasevich; Neil Horman; David S. Miller; linux-sctp@xxxxxxxxxxxxxxx; netdev; LKML; Eric Dumazet; Marcelo Ricardo Leitner
> Cc: syzkaller; Kostya Serebryany; Alexander Potapenko; Sasha Levin
> Subject: net/sctp: use-after-free in __sctp_connect
>

...

>
> On commit 03891f9c853d5c4473224478a1e03ea00d70ff8d (Jan 11).

This is the git commit/(version) he was using --^

Marcelo