Re: [RESEND PATCH v2] net/x25: Fix null-ptr-deref in x25_connect

From: Xie He
Date: Wed Nov 11 2020 - 06:38:21 EST


> This fixes a regression for blocking connects introduced by commit
> 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect").

> The x25->neighbour is already set to "NULL" by x25_disconnect() now,
> while a blocking connect is waiting in
> x25_wait_for_connection_establishment(). Therefore x25->neighbour must
> not be accessed here again and x25->state is also already set to
> X25_STATE_0 by x25_disconnect().

> Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect")
> Signed-off-by: Martin Schiller <ms@xxxxxxxxxx>

Oh. Sorry, I didn't see your patch. I just submitted another patch to fix
the same problem.

I also found another problem introduced by the same regression commit,
which I was also trying to fix in my patch.

See:
http://patchwork.ozlabs.org/project/netdev/patch/20201111100424.3989-1-xie.he.0141@xxxxxxxxx/