6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hou Tao <houtao1@xxxxxxxxxx> [ Upstream commit baa8fdecd87bb8751237b45e3bcb5a179e5a12ca ] With pcpu_alloc_size() in place, check whether or not the size of the dynamic per-cpu area is matched with unit_size. Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> Link: https://lore.kernel.org/r/20231020133202.4043247-4-houtao@xxxxxxxxxxxxxxx Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Stable-dep-of: 7ac5c53e0073 ("bpf: Use c->unit_size to select target cache during free") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/bpf/memalloc.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 956f80ee6f5c..9657d5951d78 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -491,21 +491,17 @@ static int check_obj_size(struct bpf_mem_cache *c, unsigned int idx) struct llist_node *first; unsigned int obj_size; - /* For per-cpu allocator, the size of free objects in free list doesn't - * match with unit_size and now there is no way to get the size of - * per-cpu pointer saved in free object, so just skip the checking. - */ - if (c->percpu_size) - return 0; - first = c->free_llist.first; if (!first) return 0; - obj_size = ksize(first); + if (c->percpu_size) + obj_size = pcpu_alloc_size(((void **)first)[1]); + else + obj_size = ksize(first); if (obj_size != c->unit_size) { - WARN_ONCE(1, "bpf_mem_cache[%u]: unexpected object size %u, expect %u\n", - idx, obj_size, c->unit_size); + WARN_ONCE(1, "bpf_mem_cache[%u]: percpu %d, unexpected object size %u, expect %u\n", + idx, c->percpu_size, obj_size, c->unit_size); return -EINVAL; } return 0; @@ -967,6 +963,12 @@ void notrace *bpf_mem_cache_alloc_flags(struct bpf_mem_alloc *ma, gfp_t flags) return !ret ? NULL : ret + LLIST_NODE_SZ; } +/* The alignment of dynamic per-cpu area is 8, so c->unit_size and the + * actual size of dynamic per-cpu area will always be matched and there is + * no need to adjust size_index for per-cpu allocation. However for the + * simplicity of the implementation, use an unified size_index for both + * kmalloc and per-cpu allocation. + */ static __init int bpf_mem_cache_adjust_size(void) { unsigned int size; -- 2.43.0
