ipc/sem: do not use ipc_rcu_free()

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.

Link: http://lkml.kernel.org/r/20170525185107.12869-6-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>
This commit is contained in:
Kees Cook 2017-07-12 14:34:50 -07:00 коммит произвёл Linus Torvalds
Родитель f8dbe8d290
Коммит 1b4654ef72
1 изменённых файлов: 7 добавлений и 2 удалений

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@ -258,13 +258,18 @@ static void merge_queues(struct sem_array *sma)
} }
} }
static void __sem_free(struct sem_array *sma)
{
kvfree(sma);
}
static void sem_rcu_free(struct rcu_head *head) static void sem_rcu_free(struct rcu_head *head)
{ {
struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu); struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
struct sem_array *sma = container_of(p, struct sem_array, sem_perm); struct sem_array *sma = container_of(p, struct sem_array, sem_perm);
security_sem_free(sma); security_sem_free(sma);
ipc_rcu_free(head); __sem_free(sma);
} }
/* /*
@ -482,7 +487,7 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params)
sma->sem_perm.security = NULL; sma->sem_perm.security = NULL;
retval = security_sem_alloc(sma); retval = security_sem_alloc(sma);
if (retval) { if (retval) {
ipc_rcu_putref(&sma->sem_perm, ipc_rcu_free); __sem_free(sma);
return retval; return retval;
} }