From: Kees Cook <keescook@xxxxxxxxxxxx> Subject: 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@xxxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- ipc/msg.c | 2 -- ipc/sem.c | 1 - ipc/shm.c | 2 -- ipc/util.c | 1 + 4 files changed, 1 insertion(+), 5 deletions(-) diff -puN ipc/msg.c~ipc-move-atomic_set-to-where-it-is-needed ipc/msg.c --- a/ipc/msg.c~ipc-move-atomic_set-to-where-it-is-needed +++ a/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 -puN ipc/sem.c~ipc-move-atomic_set-to-where-it-is-needed ipc/sem.c --- a/ipc/sem.c~ipc-move-atomic_set-to-where-it-is-needed +++ a/ipc/sem.c @@ -465,7 +465,6 @@ static struct sem_array *sem_alloc(size_ return NULL; memset(sma, 0, size); - atomic_set(&sma->sem_perm.refcount, 1); return sma; } diff -puN ipc/shm.c~ipc-move-atomic_set-to-where-it-is-needed ipc/shm.c --- a/ipc/shm.c~ipc-move-atomic_set-to-where-it-is-needed +++ a/ipc/shm.c @@ -526,8 +526,6 @@ static struct shmid_kernel *shm_alloc(vo if (unlikely(!shp)) return NULL; - atomic_set(&shp->shm_perm.refcount, 1); - return shp; } diff -puN ipc/util.c~ipc-move-atomic_set-to-where-it-is-needed ipc/util.c --- a/ipc/util.c~ipc-move-atomic_set-to-where-it-is-needed +++ a/ipc/util.c @@ -232,6 +232,7 @@ int ipc_addid(struct ipc_ids *ids, struc idr_preload(GFP_KERNEL); + atomic_set(&new->refcount, 1); spin_lock_init(&new->lock); new->deleted = false; rcu_read_lock(); _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
