Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751349AbdCQMLR (ORCPT ); Fri, 17 Mar 2017 08:11:17 -0400 Received: from mga06.intel.com ([134.134.136.31]:62452 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751035AbdCQMLL (ORCPT ); Fri, 17 Mar 2017 08:11:11 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,176,1486454400"; d="scan'208";a="78173602" 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 02/23] net, sunrpc: convert gss_cl_ctx.count from atomic_t to refcount_t Date: Fri, 17 Mar 2017 14:10:25 +0200 Message-Id: <1489752646-8749-3-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: 2040 Lines: 68 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/linux/sunrpc/auth_gss.h | 3 ++- net/sunrpc/auth_gss/auth_gss.c | 6 +++--- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/include/linux/sunrpc/auth_gss.h b/include/linux/sunrpc/auth_gss.h index 36eebc4..cebdf87 100644 --- a/include/linux/sunrpc/auth_gss.h +++ b/include/linux/sunrpc/auth_gss.h @@ -13,6 +13,7 @@ #define _LINUX_SUNRPC_AUTH_GSS_H #ifdef __KERNEL__ +#include #include #include #include @@ -65,7 +66,7 @@ struct rpc_gss_init_res { * the wire when communicating with a server. */ struct gss_cl_ctx { - atomic_t count; + refcount_t count; enum rpc_gss_proc gc_proc; u32 gc_seq; spinlock_t gc_seq_lock; diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 4f16953..72f129c 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -117,14 +117,14 @@ static const struct rpc_pipe_ops gss_upcall_ops_v1; static inline struct gss_cl_ctx * gss_get_ctx(struct gss_cl_ctx *ctx) { - atomic_inc(&ctx->count); + refcount_inc(&ctx->count); return ctx; } static inline void gss_put_ctx(struct gss_cl_ctx *ctx) { - if (atomic_dec_and_test(&ctx->count)) + if (refcount_dec_and_test(&ctx->count)) gss_free_ctx(ctx); } @@ -200,7 +200,7 @@ gss_alloc_context(void) ctx->gc_proc = RPC_GSS_PROC_DATA; ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ spin_lock_init(&ctx->gc_seq_lock); - atomic_set(&ctx->count,1); + refcount_set(&ctx->count,1); } return ctx; } -- 2.7.4