diff --git a/mm/slub.c b/mm/slub.c index 8657ab838b82..97bb5b8d935f 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -261,6 +261,18 @@ static inline void *get_freepointer(struct kmem_cache *s, void *object) return *(void **)(object + s->offset); } +static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) +{ + void *p; + +#ifdef CONFIG_DEBUG_PAGEALLOC + probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p)); +#else + p = get_freepointer(s, object); +#endif + return p; +} + static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) { *(void **)(object + s->offset) = fp; @@ -1933,7 +1945,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s, if (unlikely(!this_cpu_cmpxchg_double( s->cpu_slab->freelist, s->cpu_slab->tid, object, tid, - get_freepointer(s, object), next_tid(tid)))) { + get_freepointer_safe(s, object), next_tid(tid)))) { note_cmpxchg_failure("slab_alloc", s, tid); goto redo;