Re: [PATCH 5.10 09/38] llc: fix netdevice reference leaks in llc_ui_bind()

Pavel Machek
2022-03-26T21:35:16Z

[-- Attachment #1: Type: text/plain, Size: 1378 bytes --]

Hi!

> > Can someone check this? AFAICT this is buggy.
> >
> > static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
> > {
> > struct sock *sk = sock->sk;
> > struct llc_sock *llc = llc_sk(sk);
> > struct llc_sap *sap;
> > int rc = -EINVAL;
> >
> > if (!sock_flag(sk, SOCK_ZAPPED))
> > goto out;
> >
> > There are 'goto out's from both before dev_get() and after it,
> > dev_put() will be called with NULL pointer. dev_put() can't handle
> > NULL at least in the old kernels... this is simply confused.
> >
> > Mainline has dev_put_track() there, but I see same confusion.
> >
> > Best regards,
>
> commit 2d327a79ee17 ("llc: only change llc->dev when bind() succeeds"),
> https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=2d327a79ee176930dc72c131a970c891d367c1dc
>
> Should be in mainline on Thursday, LMK if we need to accelerate.
> IDK if anyone enables LLC2.

Thank you, yes, that looks good at the fast glance.

But this patch does more harm than good on its own, so I believe it
should be dropped for now, and only queued when the fixes are
available.

Best regards,
Pavel
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 195 bytes --]