From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: [PATCH] Revert "net/ipv6: fix metrics leak" Date: Wed, 01 Aug 2018 21:33:37 -0700 (PDT) Message-ID: <20180801.213337.2028479572082136309.davem@davemloft.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from shards.monkeyblade.net ([23.128.96.9]:59578 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725765AbeHBGWy (ORCPT ); Thu, 2 Aug 2018 02:22:54 -0400 Received: from localhost (unknown [172.56.41.190]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 4D35D1009723E for ; Wed, 1 Aug 2018 21:33:41 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: This reverts commit df18b50448fab1dff093731dfd0e25e77e1afcd1. This change causes other problems and use-after-free situations as found by syzbot. Signed-off-by: David S. Miller --- net/ipv6/ip6_fib.c | 18 ++++-------------- 1 file changed, 4 insertions(+), 14 deletions(-) diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 211a2d437b56..d212738e9d10 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -167,22 +167,11 @@ struct fib6_info *fib6_info_alloc(gfp_t gfp_flags) return f6i; } -static void fib6_metrics_release(struct fib6_info *f6i) -{ - struct dst_metrics *m; - - if (!f6i) - return; - - m = f6i->fib6_metrics; - if (m != &dst_default_metrics && refcount_dec_and_test(&m->refcnt)) - kfree(m); -} - void fib6_info_destroy_rcu(struct rcu_head *head) { struct fib6_info *f6i = container_of(head, struct fib6_info, rcu); struct rt6_exception_bucket *bucket; + struct dst_metrics *m; WARN_ON(f6i->fib6_node); @@ -212,7 +201,9 @@ void fib6_info_destroy_rcu(struct rcu_head *head) if (f6i->fib6_nh.nh_dev) dev_put(f6i->fib6_nh.nh_dev); - fib6_metrics_release(f6i); + m = f6i->fib6_metrics; + if (m != &dst_default_metrics && refcount_dec_and_test(&m->refcnt)) + kfree(m); kfree(f6i); } @@ -896,7 +887,6 @@ static void fib6_drop_pcpu_from(struct fib6_info *f6i, from = rcu_dereference_protected(pcpu_rt->from, lockdep_is_held(&table->tb6_lock)); - fib6_metrics_release(from); rcu_assign_pointer(pcpu_rt->from, NULL); fib6_info_release(from); } -- 2.17.1