Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751741AbdCQMTy (ORCPT ); Fri, 17 Mar 2017 08:19:54 -0400 Received: from mga11.intel.com ([192.55.52.93]:57194 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750999AbdCQMQv (ORCPT ); Fri, 17 Mar 2017 08:16:51 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,176,1486454400"; d="scan'208";a="78174327" From: Elena Reshetova To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, davem@davemloft.net, linux-x25@vger.kernel.org, linux-sctp@vger.kernel.org, vyasevich@gmail.com, nhorman@tuxdriver.com, linux-hams@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@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, ralf@linux-mips.org, peterz@infradead.org, keescook@chromium.org, Elena Reshetova , Hans Liljestrand , David Windsor Subject: [PATCH 21/23] net, ax25: convert ax25_uid_assoc.refcount from atomic_t to refcount_t Date: Fri, 17 Mar 2017 14:10:44 +0200 Message-Id: <1489752646-8749-22-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1489752646-8749-1-git-send-email-elena.reshetova@intel.com> References: <1489752646-8749-1-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: 1931 Lines: 66 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/ax25.h | 8 ++++---- net/ax25/ax25_uid.c | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/include/net/ax25.h b/include/net/ax25.h index e602f81..edd82f0 100644 --- a/include/net/ax25.h +++ b/include/net/ax25.h @@ -11,7 +11,7 @@ #include #include #include -#include +#include #include #include @@ -158,7 +158,7 @@ enum { typedef struct ax25_uid_assoc { struct hlist_node uid_node; - atomic_t refcount; + refcount_t refcount; kuid_t uid; ax25_address call; } ax25_uid_assoc; @@ -167,11 +167,11 @@ typedef struct ax25_uid_assoc { hlist_for_each_entry(__ax25, list, uid_node) #define ax25_uid_hold(ax25) \ - atomic_inc(&((ax25)->refcount)) + refcount_inc(&((ax25)->refcount)) static inline void ax25_uid_put(ax25_uid_assoc *assoc) { - if (atomic_dec_and_test(&assoc->refcount)) { + if (refcount_dec_and_test(&assoc->refcount)) { kfree(assoc); } } diff --git a/net/ax25/ax25_uid.c b/net/ax25/ax25_uid.c index 0403b0d..83b035f 100644 --- a/net/ax25/ax25_uid.c +++ b/net/ax25/ax25_uid.c @@ -107,7 +107,7 @@ int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax) if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL) return -ENOMEM; - atomic_set(&ax25_uid->refcount, 1); + refcount_set(&ax25_uid->refcount, 1); ax25_uid->uid = sax25_kuid; ax25_uid->call = sax->sax25_call; -- 2.7.4