Re: net/dccp: dccp_create_openreq_child freed held lock

[Arnaldo Carvalho de Melo]

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
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;
                }