From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938965AbdEYSzL (ORCPT ); Thu, 25 May 2017 14:55:11 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:35801 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1424910AbdEYSvW (ORCPT ); Thu, 25 May 2017 14:51:22 -0400 From: Manfred Spraul To: mtk.manpages@gmail.com, Andrew Morton , Kees Cook Cc: LKML , 1vier1@web.de, Davidlohr Bueso , mingo@kernel.org, peterz@infradead.org, fabf@skynet.be, Manfred Spraul Subject: [PATCH 06/20] ipc/shm: Do not use ipc_rcu_free() Date: Thu, 25 May 2017 20:50:53 +0200 Message-Id: <20170525185107.12869-7-manfred@colorfullife.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170525185107.12869-1-manfred@colorfullife.com> References: <20170508222345.GA52073@beast> <20170525185107.12869-1-manfred@colorfullife.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kees Cook Avoid using ipc_rcu_free, since it just re-finds the original structure pointer. For the pre-list-init failure path, there is no RCU needed, since it was just allocated. It can be directly freed. Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul --- ipc/shm.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index 2eb85bd..77e1bff 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -172,6 +172,11 @@ static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp) ipc_lock_object(&ipcp->shm_perm); } +static void __shm_free(struct shmid_kernel *shp) +{ + kvfree(shp); +} + static void shm_rcu_free(struct rcu_head *head) { struct kern_ipc_perm *ptr = container_of(head, struct kern_ipc_perm, @@ -179,7 +184,7 @@ static void shm_rcu_free(struct rcu_head *head) struct shmid_kernel *shp = container_of(ptr, struct shmid_kernel, shm_perm); security_shm_free(shp); - ipc_rcu_free(head); + __shm_free(shp); } static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s) @@ -557,7 +562,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) shp->shm_perm.security = NULL; error = security_shm_alloc(shp); if (error) { - ipc_rcu_putref(&shp->shm_perm, ipc_rcu_free); + __shm_free(shp); return error; } -- 2.9.3