1 files changed, 33 insertions, 48 deletions

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 77c3adf40e50..07b948288f84 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -26,13 +26,12 @@
 #include <linux/memcontrol.h>
 #include <linux/stackdepot.h>
 
-#define CREATE_TRACE_POINTS
-#include <trace/events/kmem.h>
-
 #include "internal.h"
-
 #include "slab.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/kmem.h>
+
 enum slab_state slab_state;
 LIST_HEAD(slab_caches);
 DEFINE_MUTEX(slab_mutex);
@@ -105,33 +104,6 @@ static inline int kmem_cache_sanity_check(const char *name, unsigned int size)
 }
 #endif
 
-void __kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p)
-{
-	size_t i;
-
-	for (i = 0; i < nr; i++) {
-		if (s)
-			kmem_cache_free(s, p[i]);
-		else
-			kfree(p[i]);
-	}
-}
-
-int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr,
-								void **p)
-{
-	size_t i;
-
-	for (i = 0; i < nr; i++) {
-		void *x = p[i] = kmem_cache_alloc(s, flags);
-		if (!x) {
-			__kmem_cache_free_bulk(s, i, p);
-			return 0;
-		}
-	}
-	return i;
-}
-
 /*
  * Figure out what the alignment of the objects will be given a set of
  * flags, a user specified alignment and the size of the objects.
@@ -420,6 +392,28 @@ kmem_cache_create(const char *name, unsigned int size, unsigned int align,
 }
 EXPORT_SYMBOL(kmem_cache_create);
 
+#ifdef SLAB_SUPPORTS_SYSFS
+/*
+ * For a given kmem_cache, kmem_cache_destroy() should only be called
+ * once or there will be a use-after-free problem. The actual deletion
+ * and release of the kobject does not need slab_mutex or cpu_hotplug_lock
+ * protection. So they are now done without holding those locks.
+ *
+ * Note that there will be a slight delay in the deletion of sysfs files
+ * if kmem_cache_release() is called indrectly from a work function.
+ */
+static void kmem_cache_release(struct kmem_cache *s)
+{
+	sysfs_slab_unlink(s);
+	sysfs_slab_release(s);
+}
+#else
+static void kmem_cache_release(struct kmem_cache *s)
+{
+	slab_kmem_cache_release(s);
+}
+#endif
+
 static void slab_caches_to_rcu_destroy_workfn(struct work_struct *work)
 {
 	LIST_HEAD(to_destroy);
@@ -446,11 +440,7 @@ static void slab_caches_to_rcu_destroy_workfn(struct work_struct *work)
 	list_for_each_entry_safe(s, s2, &to_destroy, list) {
 		debugfs_slab_release(s);
 		kfence_shutdown_cache(s);
-#ifdef SLAB_SUPPORTS_SYSFS
-		sysfs_slab_release(s);
-#else
-		slab_kmem_cache_release(s);
-#endif
+		kmem_cache_release(s);
 	}
 }
 
@@ -465,20 +455,11 @@ static int shutdown_cache(struct kmem_cache *s)
 	list_del(&s->list);
 
 	if (s->flags & SLAB_TYPESAFE_BY_RCU) {
-#ifdef SLAB_SUPPORTS_SYSFS
-		sysfs_slab_unlink(s);
-#endif
 		list_add_tail(&s->list, &slab_caches_to_rcu_destroy);
 		schedule_work(&slab_caches_to_rcu_destroy_work);
 	} else {
 		kfence_shutdown_cache(s);
 		debugfs_slab_release(s);
-#ifdef SLAB_SUPPORTS_SYSFS
-		sysfs_slab_unlink(s);
-		sysfs_slab_release(s);
-#else
-		slab_kmem_cache_release(s);
-#endif
 	}
 
 	return 0;
@@ -493,14 +474,16 @@ void slab_kmem_cache_release(struct kmem_cache *s)
 
 void kmem_cache_destroy(struct kmem_cache *s)
 {
+	int refcnt;
+
 	if (unlikely(!s) || !kasan_check_byte(s))
 		return;
 
 	cpus_read_lock();
 	mutex_lock(&slab_mutex);
 
-	s->refcount--;
-	if (s->refcount)
+	refcnt = --s->refcount;
+	if (refcnt)
 		goto out_unlock;
 
 	WARN(shutdown_cache(s),
@@ -509,6 +492,8 @@ void kmem_cache_destroy(struct kmem_cache *s)
 out_unlock:
 	mutex_unlock(&slab_mutex);
 	cpus_read_unlock();
+	if (!refcnt && !(s->flags & SLAB_TYPESAFE_BY_RCU))
+		kmem_cache_release(s);
 }
 EXPORT_SYMBOL(kmem_cache_destroy);
 
@@ -959,7 +944,7 @@ EXPORT_SYMBOL(kmalloc_order);
 void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
 {
 	void *ret = kmalloc_order(size, flags, order);
-	trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
+	trace_kmalloc(_RET_IP_, ret, NULL, size, PAGE_SIZE << order, flags);
 	return ret;
 }
 EXPORT_SYMBOL(kmalloc_order_trace);