Commit 69721203 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
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libbpf: Use libbpf_mem_ensure() when allocating new map 



Reuse libbpf_mem_ensure() when adding a new map to the list of maps
inside bpf_object. It takes care of proper resizing and reallocating of
map array and zeroing out newly allocated memory.

Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220428041523.4089853-3-andrii@kernel.org
parent b198881d

tools/lib/bpf/libbpf.c

+10 −27
Original line number Diff line number Diff line
@@ -1433,36 +1433,19 @@ static int find_elf_var_offset(const struct bpf_object *obj, const char *name, _ 


static struct bpf_map *bpf_object__add_map(struct bpf_object *obj)

{

	struct bpf_map *new_maps;

	size_t new_cap;

	int i;



	if (obj->nr_maps < obj->maps_cap)

		return &obj->maps[obj->nr_maps++];



	new_cap = max((size_t)4, obj->maps_cap * 3 / 2);

	new_maps = libbpf_reallocarray(obj->maps, new_cap, sizeof(*obj->maps));

	if (!new_maps) {

		pr_warn("alloc maps for object failed\n");

		return ERR_PTR(-ENOMEM);

	}

	struct bpf_map *map;

	int err;



	obj->maps_cap = new_cap;

	obj->maps = new_maps;

	err = libbpf_ensure_mem((void **)&obj->maps, &obj->maps_cap,

				sizeof(*obj->maps), obj->nr_maps + 1);

	if (err)

		return ERR_PTR(err);



	/* zero out new maps */

	memset(obj->maps + obj->nr_maps, 0,

	       (obj->maps_cap - obj->nr_maps) * sizeof(*obj->maps));

	/*

	 * fill all fd with -1 so won't close incorrect fd (fd=0 is stdin)

	 * when failure (zclose won't close negative fd)).

	 */

	for (i = obj->nr_maps; i < obj->maps_cap; i++) {

		obj->maps[i].fd = -1;

		obj->maps[i].inner_map_fd = -1;

	}

	map = &obj->maps[obj->nr_maps++];

	map->fd = -1;

	map->inner_map_fd = -1;



	return &obj->maps[obj->nr_maps++];

	return map;

}



static size_t bpf_map_mmap_sz(const struct bpf_map *map)