Use __GFP_NO_OBJ_EXT to prevent recursions when allocating slabobj_ext objects. Also prevent slabobj_ext allocations for kmem_cache objects. Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> --- mm/slab.h | 6 ++++++ mm/slab_common.c | 2 ++ 2 files changed, 8 insertions(+) diff --git a/mm/slab.h b/mm/slab.h index 25d14b3a7280..b1c22dc87047 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -450,6 +450,12 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p) if (!need_slab_obj_ext()) return NULL; + if (s->flags & SLAB_NO_OBJ_EXT) + return NULL; + + if (flags & __GFP_NO_OBJ_EXT) + return NULL; + slab = virt_to_slab(p); if (!slab_obj_exts(slab) && WARN(alloc_slab_obj_exts(slab, s, flags, false), diff --git a/mm/slab_common.c b/mm/slab_common.c index f11cc072b01e..42777d66d0e3 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -220,6 +220,8 @@ int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s, void *vec; gfp &= ~OBJCGS_CLEAR_MASK; + /* Prevent recursive extension vector allocation */ + gfp |= __GFP_NO_OBJ_EXT; vec = kcalloc_node(objects, sizeof(struct slabobj_ext), gfp, slab_nid(slab)); if (!vec) -- 2.40.1.495.gc816e09b53d-goog
