Commit 5c04433d authored by Song Liu's avatar Song Liu Committed by Martin KaFai Lau
Browse files

bpf: Charge modmem for struct_ops trampoline 



Current code charges modmem for regular trampoline, but not for struct_ops
trampoline. Add bpf_jit_[charge|uncharge]_modmem() to struct_ops so the
trampoline is charged in both cases.

Signed-off-by: default avatarSong Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230914222542.2986059-1-song@kernel.org


Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
parent 971f7c32

kernel/bpf/bpf_struct_ops.c

+22 −4
Original line number Diff line number Diff line
@@ -615,7 +615,10 @@ static void __bpf_struct_ops_map_free(struct bpf_map *map) 
	if (st_map->links)

		bpf_struct_ops_map_put_progs(st_map);

	bpf_map_area_free(st_map->links);

	if (st_map->image) {

		bpf_jit_free_exec(st_map->image);

		bpf_jit_uncharge_modmem(PAGE_SIZE);

	}

	bpf_map_area_free(st_map->uvalue);

	bpf_map_area_free(st_map);

}
@@ -657,6 +660,7 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) 
	struct bpf_struct_ops_map *st_map;

	const struct btf_type *t, *vt;

	struct bpf_map *map;

	int ret;



	st_ops = bpf_struct_ops_find_value(attr->btf_vmlinux_value_type_id);

	if (!st_ops)
@@ -681,12 +685,27 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) 
	st_map->st_ops = st_ops;

	map = &st_map->map;



	ret = bpf_jit_charge_modmem(PAGE_SIZE);

	if (ret) {

		__bpf_struct_ops_map_free(map);

		return ERR_PTR(ret);

	}



	st_map->image = bpf_jit_alloc_exec(PAGE_SIZE);

	if (!st_map->image) {

		/* __bpf_struct_ops_map_free() uses st_map->image as flag

		 * for "charged or not". In this case, we need to unchange

		 * here.

		 */

		bpf_jit_uncharge_modmem(PAGE_SIZE);

		__bpf_struct_ops_map_free(map);

		return ERR_PTR(-ENOMEM);

	}

	st_map->uvalue = bpf_map_area_alloc(vt->size, NUMA_NO_NODE);

	st_map->links =

		bpf_map_area_alloc(btf_type_vlen(t) * sizeof(struct bpf_links *),

				   NUMA_NO_NODE);

	st_map->image = bpf_jit_alloc_exec(PAGE_SIZE);

	if (!st_map->uvalue || !st_map->links || !st_map->image) {

	if (!st_map->uvalue || !st_map->links) {

		__bpf_struct_ops_map_free(map);

		return ERR_PTR(-ENOMEM);

	}
@@ -907,4 +926,3 @@ int bpf_struct_ops_link_create(union bpf_attr *attr) 
	kfree(link);

	return err;

}