Return-Path: Received: from mga02.intel.com ([134.134.136.20]:18651 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752665AbdGDM45 (ORCPT ); Tue, 4 Jul 2017 08:56:57 -0400 From: Elena Reshetova To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-decnet-user@lists.sourceforge.net, davem@davemloft.net, jmorris@namei.org, kaber@trash.net, yoshfuji@linux-ipv6.org, kuznet@ms2.inr.ac.ru, 3chas3@gmail.com, ralf@linux-mips.org, stephen@networkplumber.org, jchapman@katalix.com, jhs@mojatatu.com, bridge@lists.linux-foundation.org, linux-hams@vger.kernel.org, linux-x25@vger.kernel.org, peterz@infradead.org, keescook@chromium.org, linux-rdma@vger.kernel.org, linux-sctp@vger.kernel.org, vyasevich@gmail.com, nhorman@tuxdriver.com, linux-nfs@vger.kernel.org, zyan@redhat.com, sage@redhat.com, bfields@fieldses.org, jlayton@poochiereds.net, steffen.klassert@secunet.com, herbert@gondor.apana.org.au, santosh.shilimkar@oracle.com, jreuter@yaina.de, Elena Reshetova , Hans Liljestrand , David Windsor Subject: [PATCH 22/36] net, rds: convert rds_mr.r_refcount from atomic_t to refcount_t Date: Tue, 4 Jul 2017 15:53:17 +0300 Message-Id: <1499172811-16271-23-git-send-email-elena.reshetova@intel.com> In-Reply-To: <1499172811-16271-1-git-send-email-elena.reshetova@intel.com> References: <1499172811-16271-1-git-send-email-elena.reshetova@intel.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: 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 --- net/rds/rdma.c | 10 +++++----- net/rds/rds.h | 4 ++-- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/net/rds/rdma.c b/net/rds/rdma.c index f06fac4..8886f15 100644 --- a/net/rds/rdma.c +++ b/net/rds/rdma.c @@ -84,7 +84,7 @@ static struct rds_mr *rds_mr_tree_walk(struct rb_root *root, u64 key, if (insert) { rb_link_node(&insert->r_rb_node, parent, p); rb_insert_color(&insert->r_rb_node, root); - atomic_inc(&insert->r_refcount); + refcount_inc(&insert->r_refcount); } return NULL; } @@ -99,7 +99,7 @@ static void rds_destroy_mr(struct rds_mr *mr) unsigned long flags; rdsdebug("RDS: destroy mr key is %x refcnt %u\n", - mr->r_key, atomic_read(&mr->r_refcount)); + mr->r_key, refcount_read(&mr->r_refcount)); if (test_and_set_bit(RDS_MR_DEAD, &mr->r_state)) return; @@ -223,7 +223,7 @@ static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args, goto out; } - atomic_set(&mr->r_refcount, 1); + refcount_set(&mr->r_refcount, 1); RB_CLEAR_NODE(&mr->r_rb_node); mr->r_trans = rs->rs_transport; mr->r_sock = rs; @@ -307,7 +307,7 @@ static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args, rdsdebug("RDS: get_mr key is %x\n", mr->r_key); if (mr_ret) { - atomic_inc(&mr->r_refcount); + refcount_inc(&mr->r_refcount); *mr_ret = mr; } @@ -756,7 +756,7 @@ int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm, if (!mr) err = -EINVAL; /* invalid r_key */ else - atomic_inc(&mr->r_refcount); + refcount_inc(&mr->r_refcount); spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); if (mr) { diff --git a/net/rds/rds.h b/net/rds/rds.h index 35ceaa2..ea72d6e 100644 --- a/net/rds/rds.h +++ b/net/rds/rds.h @@ -277,7 +277,7 @@ struct rds_incoming { struct rds_mr { struct rb_node r_rb_node; - atomic_t r_refcount; + refcount_t r_refcount; u32 r_key; /* A copy of the creation flags */ @@ -857,7 +857,7 @@ int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm, void __rds_put_mr_final(struct rds_mr *mr); static inline void rds_mr_put(struct rds_mr *mr) { - if (atomic_dec_and_test(&mr->r_refcount)) + if (refcount_dec_and_test(&mr->r_refcount)) __rds_put_mr_final(mr); } -- 2.7.4