diff options
Diffstat (limited to 'kernel/bpf/map_iter.c')
| -rw-r--r-- | kernel/bpf/map_iter.c | 155 |
1 files changed, 141 insertions, 14 deletions
diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c index c69071e334bf..9575314f40a6 100644 --- a/kernel/bpf/map_iter.c +++ b/kernel/bpf/map_iter.c @@ -4,9 +4,10 @@ #include <linux/fs.h> #include <linux/filter.h> #include <linux/kernel.h> +#include <linux/btf_ids.h> struct bpf_iter_seq_map_info { - u32 mid; + u32 map_id; }; static void *bpf_map_seq_start(struct seq_file *seq, loff_t *pos) @@ -14,27 +15,23 @@ static void *bpf_map_seq_start(struct seq_file *seq, loff_t *pos) struct bpf_iter_seq_map_info *info = seq->private; struct bpf_map *map; - map = bpf_map_get_curr_or_next(&info->mid); + map = bpf_map_get_curr_or_next(&info->map_id); if (!map) return NULL; - ++*pos; + if (*pos == 0) + ++*pos; return map; } static void *bpf_map_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct bpf_iter_seq_map_info *info = seq->private; - struct bpf_map *map; ++*pos; - ++info->mid; + ++info->map_id; bpf_map_put((struct bpf_map *)v); - map = bpf_map_get_curr_or_next(&info->mid); - if (!map) - return NULL; - - return map; + return bpf_map_get_curr_or_next(&info->map_id); } struct bpf_iter__bpf_map { @@ -81,22 +78,152 @@ static const struct seq_operations bpf_map_seq_ops = { .show = bpf_map_seq_show, }; -static const struct bpf_iter_reg bpf_map_reg_info = { - .target = "bpf_map", +BTF_ID_LIST_GLOBAL_SINGLE(btf_bpf_map_id, struct, bpf_map) + +static const struct bpf_iter_seq_info bpf_map_seq_info = { .seq_ops = &bpf_map_seq_ops, .init_seq_private = NULL, .fini_seq_private = NULL, .seq_priv_size = sizeof(struct bpf_iter_seq_map_info), +}; + +static struct bpf_iter_reg bpf_map_reg_info = { + .target = "bpf_map", .ctx_arg_info_size = 1, .ctx_arg_info = { { offsetof(struct bpf_iter__bpf_map, map), - PTR_TO_BTF_ID_OR_NULL }, + PTR_TO_BTF_ID_OR_NULL | PTR_TRUSTED }, + }, + .seq_info = &bpf_map_seq_info, +}; + +static int bpf_iter_attach_map(struct bpf_prog *prog, + union bpf_iter_link_info *linfo, + struct bpf_iter_aux_info *aux) +{ + u32 key_acc_size, value_acc_size, key_size, value_size; + struct bpf_map *map; + bool is_percpu = false; + int err = -EINVAL; + + if (!linfo->map.map_fd) + return -EBADF; + + map = bpf_map_get_with_uref(linfo->map.map_fd); + if (IS_ERR(map)) + return PTR_ERR(map); + + if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) + is_percpu = true; + else if (map->map_type != BPF_MAP_TYPE_HASH && + map->map_type != BPF_MAP_TYPE_LRU_HASH && + map->map_type != BPF_MAP_TYPE_ARRAY) + goto put_map; + + key_acc_size = prog->aux->max_rdonly_access; + value_acc_size = prog->aux->max_rdwr_access; + key_size = map->key_size; + if (!is_percpu) + value_size = map->value_size; + else + value_size = round_up(map->value_size, 8) * num_possible_cpus(); + + if (key_acc_size > key_size || value_acc_size > value_size) { + err = -EACCES; + goto put_map; + } + + aux->map = map; + return 0; + +put_map: + bpf_map_put_with_uref(map); + return err; +} + +static void bpf_iter_detach_map(struct bpf_iter_aux_info *aux) +{ + bpf_map_put_with_uref(aux->map); +} + +void bpf_iter_map_show_fdinfo(const struct bpf_iter_aux_info *aux, + struct seq_file *seq) +{ + seq_printf(seq, "map_id:\t%u\n", aux->map->id); +} + +int bpf_iter_map_fill_link_info(const struct bpf_iter_aux_info *aux, + struct bpf_link_info *info) +{ + info->iter.map.map_id = aux->map->id; + return 0; +} + +DEFINE_BPF_ITER_FUNC(bpf_map_elem, struct bpf_iter_meta *meta, + struct bpf_map *map, void *key, void *value) + +static const struct bpf_iter_reg bpf_map_elem_reg_info = { + .target = "bpf_map_elem", + .attach_target = bpf_iter_attach_map, + .detach_target = bpf_iter_detach_map, + .show_fdinfo = bpf_iter_map_show_fdinfo, + .fill_link_info = bpf_iter_map_fill_link_info, + .ctx_arg_info_size = 2, + .ctx_arg_info = { + { offsetof(struct bpf_iter__bpf_map_elem, key), + PTR_TO_BUF | PTR_MAYBE_NULL | MEM_RDONLY }, + { offsetof(struct bpf_iter__bpf_map_elem, value), + PTR_TO_BUF | PTR_MAYBE_NULL }, }, }; static int __init bpf_map_iter_init(void) { - return bpf_iter_reg_target(&bpf_map_reg_info); + int ret; + + bpf_map_reg_info.ctx_arg_info[0].btf_id = *btf_bpf_map_id; + ret = bpf_iter_reg_target(&bpf_map_reg_info); + if (ret) + return ret; + + return bpf_iter_reg_target(&bpf_map_elem_reg_info); } late_initcall(bpf_map_iter_init); + +__bpf_kfunc_start_defs(); + +__bpf_kfunc s64 bpf_map_sum_elem_count(const struct bpf_map *map) +{ + s64 *pcount; + s64 ret = 0; + int cpu; + + if (!map || !map->elem_count) + return 0; + + for_each_possible_cpu(cpu) { + pcount = per_cpu_ptr(map->elem_count, cpu); + ret += READ_ONCE(*pcount); + } + return ret; +} + +__bpf_kfunc_end_defs(); + +BTF_KFUNCS_START(bpf_map_iter_kfunc_ids) +BTF_ID_FLAGS(func, bpf_map_sum_elem_count, KF_TRUSTED_ARGS) +BTF_KFUNCS_END(bpf_map_iter_kfunc_ids) + +static const struct btf_kfunc_id_set bpf_map_iter_kfunc_set = { + .owner = THIS_MODULE, + .set = &bpf_map_iter_kfunc_ids, +}; + +static int init_subsystem(void) +{ + return register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &bpf_map_iter_kfunc_set); +} +late_initcall(init_subsystem); 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