From 3d3653f9732c73feb8c4addfc1cbdaa292a399fa Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Wed, 12 Jul 2017 14:35:22 -0700
Subject: [PATCH 16/20] ipc: move atomic_set() to where it is needed
Git-commit: 3d3653f9732c73feb8c4addfc1cbdaa292a399fa
Patch-mainline: v4.13-rc1
References: bsc#1050323
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 <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
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();
--
2.12.0