diff options
Diffstat (limited to 'net/bpf/bpf_dummy_struct_ops.c')
| -rw-r--r-- | net/bpf/bpf_dummy_struct_ops.c | 99 |
1 files changed, 81 insertions, 18 deletions
diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c index 8906f7bdf4a9..f71f67c6896b 100644 --- a/net/bpf/bpf_dummy_struct_ops.c +++ b/net/bpf/bpf_dummy_struct_ops.c @@ -7,7 +7,7 @@ #include <linux/bpf.h> #include <linux/btf.h> -extern struct bpf_struct_ops bpf_bpf_dummy_ops; +static struct bpf_struct_ops bpf_bpf_dummy_ops; /* A common type for test_N with return value in bpf_dummy_ops */ typedef int (*dummy_ops_test_ret_fn)(struct bpf_dummy_ops_state *state, ...); @@ -22,6 +22,8 @@ struct bpf_dummy_ops_test_args { struct bpf_dummy_ops_state state; }; +static struct btf *bpf_dummy_ops_btf; + static struct bpf_dummy_ops_test_args * dummy_ops_init_args(const union bpf_attr *kattr, unsigned int nr) { @@ -77,6 +79,51 @@ static int dummy_ops_call_op(void *image, struct bpf_dummy_ops_test_args *args) args->args[3], args->args[4]); } +static const struct bpf_ctx_arg_aux *find_ctx_arg_info(struct bpf_prog_aux *aux, int offset) +{ + int i; + + for (i = 0; i < aux->ctx_arg_info_size; i++) + if (aux->ctx_arg_info[i].offset == offset) + return &aux->ctx_arg_info[i]; + + return NULL; +} + +/* There is only one check at the moment: + * - zero should not be passed for pointer parameters not marked as nullable. + */ +static int check_test_run_args(struct bpf_prog *prog, struct bpf_dummy_ops_test_args *args) +{ + const struct btf_type *func_proto = prog->aux->attach_func_proto; + + for (u32 arg_no = 0; arg_no < btf_type_vlen(func_proto) ; ++arg_no) { + const struct btf_param *param = &btf_params(func_proto)[arg_no]; + const struct bpf_ctx_arg_aux *info; + const struct btf_type *t; + int offset; + + if (args->args[arg_no] != 0) + continue; + + /* Program is validated already, so there is no need + * to check if t is NULL. + */ + t = btf_type_skip_modifiers(bpf_dummy_ops_btf, param->type, NULL); + if (!btf_type_is_ptr(t)) + continue; + + offset = btf_ctx_arg_offset(bpf_dummy_ops_btf, func_proto, arg_no); + info = find_ctx_arg_info(prog->aux, offset); + if (info && type_may_be_null(info->reg_type)) + continue; + + return -EINVAL; + } + + return 0; +} + extern const struct bpf_link_ops bpf_struct_ops_link_lops; int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, @@ -85,14 +132,21 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, const struct bpf_struct_ops *st_ops = &bpf_bpf_dummy_ops; const struct btf_type *func_proto; struct bpf_dummy_ops_test_args *args; - struct bpf_tramp_links *tlinks; + struct bpf_tramp_links *tlinks = NULL; struct bpf_tramp_link *link = NULL; void *image = NULL; unsigned int op_idx; + u32 image_off = 0; int prog_ret; + s32 type_id; int err; - if (prog->aux->attach_btf_id != st_ops->type_id) + type_id = btf_find_by_name_kind(bpf_dummy_ops_btf, + bpf_bpf_dummy_ops.name, + BTF_KIND_STRUCT); + if (type_id < 0) + return -EINVAL; + if (prog->aux->attach_btf_id != type_id) return -EOPNOTSUPP; func_proto = prog->aux->attach_func_proto; @@ -100,14 +154,12 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, if (IS_ERR(args)) return PTR_ERR(args); - tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); - if (!tlinks) { - err = -ENOMEM; + err = check_test_run_args(prog, args); + if (err) goto out; - } - image = arch_alloc_bpf_trampoline(PAGE_SIZE); - if (!image) { + tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); + if (!tlinks) { err = -ENOMEM; goto out; } @@ -125,11 +177,14 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, err = bpf_struct_ops_prepare_trampoline(tlinks, link, &st_ops->func_models[op_idx], &dummy_ops_test_ret_function, - image, image + PAGE_SIZE); + &image, &image_off, + true); if (err < 0) goto out; - arch_protect_bpf_trampoline(image, PAGE_SIZE); + err = arch_protect_bpf_trampoline(image, PAGE_SIZE); + if (err) + goto out; prog_ret = dummy_ops_call_op(image, args); err = dummy_ops_copy_args(args); @@ -139,7 +194,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, err = -EFAULT; out: kfree(args); - arch_free_bpf_trampoline(image, PAGE_SIZE); + bpf_struct_ops_image_free(image); if (link) bpf_link_put(&link->link); kfree(tlinks); @@ -148,6 +203,7 @@ out: static int bpf_dummy_init(struct btf *btf) { + bpf_dummy_ops_btf = btf; return 0; } @@ -169,7 +225,7 @@ static int bpf_dummy_ops_check_member(const struct btf_type *t, case offsetof(struct bpf_dummy_ops, test_sleepable): break; default: - if (prog->aux->sleepable) + if (prog->sleepable) return -EINVAL; } @@ -216,16 +272,16 @@ static int bpf_dummy_init_member(const struct btf_type *t, return -EOPNOTSUPP; } -static int bpf_dummy_reg(void *kdata) +static int bpf_dummy_reg(void *kdata, struct bpf_link *link) { return -EOPNOTSUPP; } -static void bpf_dummy_unreg(void *kdata) +static void bpf_dummy_unreg(void *kdata, struct bpf_link *link) { } -static int bpf_dummy_test_1(struct bpf_dummy_ops_state *cb) +static int bpf_dummy_ops__test_1(struct bpf_dummy_ops_state *cb__nullable) { return 0; } @@ -242,12 +298,12 @@ static int bpf_dummy_test_sleepable(struct bpf_dummy_ops_state *cb) } static struct bpf_dummy_ops __bpf_bpf_dummy_ops = { - .test_1 = bpf_dummy_test_1, + .test_1 = bpf_dummy_ops__test_1, .test_2 = bpf_dummy_test_2, .test_sleepable = bpf_dummy_test_sleepable, }; -struct bpf_struct_ops bpf_bpf_dummy_ops = { +static struct bpf_struct_ops bpf_bpf_dummy_ops = { .verifier_ops = &bpf_dummy_verifier_ops, .init = bpf_dummy_init, .check_member = bpf_dummy_ops_check_member, @@ -256,4 +312,11 @@ struct bpf_struct_ops bpf_bpf_dummy_ops = { .unreg = bpf_dummy_unreg, .name = "bpf_dummy_ops", .cfi_stubs = &__bpf_bpf_dummy_ops, + .owner = THIS_MODULE, }; + +static int __init bpf_dummy_struct_ops_init(void) +{ + return register_bpf_struct_ops(&bpf_bpf_dummy_ops, bpf_dummy_ops); +} +late_initcall(bpf_dummy_struct_ops_init); |