Re: net/dccp: dccp_create_openreq_child freed held lock

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Wed, Mar 01, 2017 at 12:35:10PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Wed, Mar 01, 2017 at 10:38:54AM +0100, Dmitry Vyukov escreveu:
> > Hello,
> > 
> > I've got the following report while running syzkaller fuzzer on
> > 86292b33d4b79ee03e2f43ea0381ef85f077c760:
> > 
> > 
> > It seems that dccp_create_openreq_child needs to unlock the sock if
> > dccp_feat_activate_values fails.
> 
> Yeah, can you please use the patch below, that mimics the error paths in
> sk_clone_new(), from where I think even the comment about it being a raw

Argh, s/sk_clone_new()/sk_clone_lock()/g

- Arnaldo

> copy came, but the bh_unlock_sock() didn't?
> 
> - Arnaldo
> 
> diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
> index 53eddf99e4f6..d20d948a98ed 100644
> --- a/net/dccp/minisocks.c
> +++ b/net/dccp/minisocks.c
> @@ -122,6 +122,7 @@ struct sock *dccp_create_openreq_child(const struct sock *sk,
>  			/* It is still raw copy of parent, so invalidate
>  			 * destructor and make plain sk_free() */
>  			newsk->sk_destruct = NULL;
> +			bh_unlock_sock(newsk);
>  			sk_free(newsk);
>  			return NULL;
>  		}