From 3d3653f9732c73feb8c4addfc1cbdaa292a399fa Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 12 Jul 2017 14:35:22 -0700 Subject: [PATCH] ipc: move atomic_set() to where it is needed Only after ipc_addid() has succeeded will refcounting be used, so move initialization into ipc_addid() and remove from open-coded *_alloc() routines. Link: http://lkml.kernel.org/r/20170525185107.12869-17-manfred@colorfullife.com Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/msg.c | 2 -- ipc/sem.c | 1 - ipc/shm.c | 2 -- ipc/util.c | 1 + 4 files changed, 1 insertion(+), 5 deletions(-) diff --git a/ipc/msg.c b/ipc/msg.c index cd90bfde89a4..770342e1d327 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -117,8 +117,6 @@ static struct msg_queue *msg_alloc(void) if (unlikely(!msq)) return NULL; - atomic_set(&msq->q_perm.refcount, 1); - return msq; } diff --git a/ipc/sem.c b/ipc/sem.c index 2b2ed56e0fde..5f137738819d 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -465,7 +465,6 @@ static struct sem_array *sem_alloc(size_t nsems) return NULL; memset(sma, 0, size); - atomic_set(&sma->sem_perm.refcount, 1); return sma; } diff --git a/ipc/shm.c b/ipc/shm.c index c5976d318ed1..d1988ef821a1 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -526,8 +526,6 @@ static struct shmid_kernel *shm_alloc(void) if (unlikely(!shp)) return NULL; - atomic_set(&shp->shm_perm.refcount, 1); - return shp; } diff --git a/ipc/util.c b/ipc/util.c index 2428dd44ca97..1a2cb02467ab 100644 --- a/ipc/util.c +++ b/ipc/util.c @@ -232,6 +232,7 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int size) idr_preload(GFP_KERNEL); + atomic_set(&new->refcount, 1); spin_lock_init(&new->lock); new->deleted = false; rcu_read_lock(); -- 2.30.2