Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754824AbdCPPaJ (ORCPT ); Thu, 16 Mar 2017 11:30:09 -0400 Received: from mga05.intel.com ([192.55.52.43]:62193 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752687AbdCPPaH (ORCPT ); Thu, 16 Mar 2017 11:30:07 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,173,1486454400"; d="scan'208";a="76190829" From: Elena Reshetova To: netdev@vger.kernel.org Cc: bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kuznet@ms2.inr.ac.ru, jmorris@namei.org, kaber@trash.net, stephen@networkplumber.org, peterz@infradead.org, keescook@chromium.org, Elena Reshetova , Hans Liljestrand , David Windsor Subject: [PATCH 14/17] net: convert inet_frag_queue.refcnt from atomic_t to refcount_t Date: Thu, 16 Mar 2017 17:29:04 +0200 Message-Id: <1489678147-21404-15-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1489678147-21404-1-git-send-email-elena.reshetova@intel.com> References: <1489678147-21404-1-git-send-email-elena.reshetova@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3560 Lines: 110 refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor --- include/net/inet_frag.h | 4 ++-- net/ipv4/inet_fragment.c | 14 +++++++------- net/ipv4/ip_fragment.c | 2 +- 3 files changed, 10 insertions(+), 10 deletions(-) diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h index 5894730..5a334bf 100644 --- a/include/net/inet_frag.h +++ b/include/net/inet_frag.h @@ -50,7 +50,7 @@ struct inet_frag_queue { spinlock_t lock; struct timer_list timer; struct hlist_node list; - atomic_t refcnt; + refcount_t refcnt; struct sk_buff *fragments; struct sk_buff *fragments_tail; ktime_t stamp; @@ -129,7 +129,7 @@ void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q, static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f) { - if (atomic_dec_and_test(&q->refcnt)) + if (refcount_dec_and_test(&q->refcnt)) inet_frag_destroy(q, f); } diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c index b5e9317..96e95e8 100644 --- a/net/ipv4/inet_fragment.c +++ b/net/ipv4/inet_fragment.c @@ -276,11 +276,11 @@ static inline void fq_unlink(struct inet_frag_queue *fq, struct inet_frags *f) void inet_frag_kill(struct inet_frag_queue *fq, struct inet_frags *f) { if (del_timer(&fq->timer)) - atomic_dec(&fq->refcnt); + refcount_dec(&fq->refcnt); if (!(fq->flags & INET_FRAG_COMPLETE)) { fq_unlink(fq, f); - atomic_dec(&fq->refcnt); + refcount_dec(&fq->refcnt); } } EXPORT_SYMBOL(inet_frag_kill); @@ -329,7 +329,7 @@ static struct inet_frag_queue *inet_frag_intern(struct netns_frags *nf, */ hlist_for_each_entry(qp, &hb->chain, list) { if (qp->net == nf && f->match(qp, arg)) { - atomic_inc(&qp->refcnt); + refcount_inc(&qp->refcnt); spin_unlock(&hb->chain_lock); qp_in->flags |= INET_FRAG_COMPLETE; inet_frag_put(qp_in, f); @@ -339,9 +339,9 @@ static struct inet_frag_queue *inet_frag_intern(struct netns_frags *nf, #endif qp = qp_in; if (!mod_timer(&qp->timer, jiffies + nf->timeout)) - atomic_inc(&qp->refcnt); + refcount_inc(&qp->refcnt); - atomic_inc(&qp->refcnt); + refcount_inc(&qp->refcnt); hlist_add_head(&qp->list, &hb->chain); spin_unlock(&hb->chain_lock); @@ -370,7 +370,7 @@ static struct inet_frag_queue *inet_frag_alloc(struct netns_frags *nf, setup_timer(&q->timer, f->frag_expire, (unsigned long)q); spin_lock_init(&q->lock); - atomic_set(&q->refcnt, 1); + refcount_set(&q->refcnt, 1); return q; } @@ -405,7 +405,7 @@ struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, spin_lock(&hb->chain_lock); hlist_for_each_entry(q, &hb->chain, list) { if (q->net == nf && f->match(q, key)) { - atomic_inc(&q->refcnt); + refcount_inc(&q->refcnt); spin_unlock(&hb->chain_lock); return q; } diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index bbe7f72..4fed6f6 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -303,7 +303,7 @@ static int ip_frag_reinit(struct ipq *qp) unsigned int sum_truesize = 0; if (!mod_timer(&qp->q.timer, jiffies + qp->q.net->timeout)) { - atomic_inc(&qp->q.refcnt); + refcount_inc(&qp->q.refcnt); return -ETIMEDOUT; } -- 2.7.4