From patchwork Sun Dec 17 08:11:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 13495792 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-qk1-f175.google.com (mail-qk1-f175.google.com [209.85.222.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D4C061FB4; Sun, 17 Dec 2023 08:11:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ern22uPA" Received: by mail-qk1-f175.google.com with SMTP id af79cd13be357-77f8e4702a6so193056985a.1; Sun, 17 Dec 2023 00:11:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702800705; x=1703405505; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=3BbvIxRBB10Pf51IIxv6h8AefewnxOFNC4H0ueS8VlE=; b=ern22uPAp4PUjDrPQfWr+/m1EC5vogoKq5KAth5Q38D8yznWeUDuSBhP9lxJ13WQwe 8oZwEC5/FG3RYYlhzi5HNjOpXRUMuGGXVvafR3NhubiaGxqvoidEH/hs5mO0sbJjBPc/ p1BsH2HR5NxXuBcJzGzGH9TEhWTqSk7mKh8x/nI0U+rScq55Ghtma8Ad+hNsQ/unfIL/ IEYVDFUY5Gl6kh8K9eHlsiyJJvabx8XRFQeTph8s7ccTjbRifDkS452CT5DDmQgNrcgD L042qPSisjahMkavzev69uN1sdKvRpQjNZ9eBZx6z7MFE6MY6eqy0kxgvYAp7HQzp2+E 2Avg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702800705; x=1703405505; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3BbvIxRBB10Pf51IIxv6h8AefewnxOFNC4H0ueS8VlE=; b=AGcvJupGROhdmMmgW6Of1LMMrm/fZJh9IdjEWZXaFd+1k18Afw4KyGn1N/Kaxo12B3 XDfJ8BORjeqWH4W7hfetEJiP6MPnbsgXijxTlv2fdOlTPEvI8lclb42DcCrPuoSPsozP JTg7Fg/BNbD3JdKv1sRSYWMxYxoM/y9Xncd9RXfLEKXA3D+4gvavkJKKfdCKDPWEx5AM /FeKzbV8pqfMw6/6LnsxalntBjsL3NIFtmmuIpf1ERlpr79M17QAYKdSqPPfnWhQj+js hBogr6SCtnX59aUw3u7LEslVIYlWajgnBvz2oLMQHgbhjGpcLdVskAiK7DCxpZ4BPU8Y Hgmg== X-Gm-Message-State: AOJu0YyQcxCho/7G0XE7bKrLShc9YTYv3CYw+++8Pn63O1mwod1TPdFr 6nwdRcAz3DHEkOeY7vdYjB+dKi9t7N8= X-Google-Smtp-Source: AGHT+IFhm754wuKtTFAz9h0a4WCA5GfcGog6khi/mQS9bZU+Wgk6leZOxq1KqGxk7H/DnlMpKHBk6g== X-Received: by 2002:a05:620a:4712:b0:76d:2725:f36f with SMTP id bs18-20020a05620a471200b0076d2725f36fmr19127243qkb.71.1702800705063; Sun, 17 Dec 2023 00:11:45 -0800 (PST) Received: from kickker.attlocal.net ([2600:1700:6cf8:1240:bb8c:c0f2:4408:50cf]) by smtp.gmail.com with ESMTPSA id c85-20020a814e58000000b005e303826838sm3399415ywb.56.2023.12.17.00.11.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 Dec 2023 00:11:44 -0800 (PST) From: thinker.li@gmail.com To: bpf@vger.kernel.org, ast@kernel.org, martin.lau@linux.dev, song@kernel.org, kernel-team@meta.com, andrii@kernel.org, drosen@google.com Cc: sinquersw@gmail.com, kuifeng@meta.com, Kui-Feng Lee , netdev@vger.kernel.org Subject: [PATCH bpf-next v14 03/14] bpf, net: introduce bpf_struct_ops_desc. Date: Sun, 17 Dec 2023 00:11:20 -0800 Message-Id: <20231217081132.1025020-4-thinker.li@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231217081132.1025020-1-thinker.li@gmail.com> References: <20231217081132.1025020-1-thinker.li@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Kui-Feng Lee Move some of members of bpf_struct_ops to bpf_struct_ops_desc. When we introduce the new API to register new bpf_struct_ops types from modules, bpf_struct_ops may destroyed when the module is unloaded. Moving these members to bpf_struct_ops_desc make these data available even when the module is unloaded. type_id is unavailabe in bpf_struct_ops anymore. Modules should get it from the btf received by kmod's init function. Cc: netdev@vger.kernel.org Signed-off-by: Kui-Feng Lee --- include/linux/bpf.h | 13 ++++-- kernel/bpf/bpf_struct_ops.c | 80 +++++++++++++++++----------------- kernel/bpf/verifier.c | 8 ++-- net/bpf/bpf_dummy_struct_ops.c | 11 ++++- net/ipv4/bpf_tcp_ca.c | 8 +++- 5 files changed, 72 insertions(+), 48 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c87c608a3689..432f37c979ff 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1683,17 +1683,22 @@ struct bpf_struct_ops { void (*unreg)(void *kdata); int (*update)(void *kdata, void *old_kdata); int (*validate)(void *kdata); - const struct btf_type *type; - const struct btf_type *value_type; const char *name; struct btf_func_model func_models[BPF_STRUCT_OPS_MAX_NR_MEMBERS]; +}; + +struct bpf_struct_ops_desc { + struct bpf_struct_ops *st_ops; + + const struct btf_type *type; + const struct btf_type *value_type; u32 type_id; u32 value_id; }; #if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL) #define BPF_MODULE_OWNER ((void *)((0xeB9FUL << 2) + POISON_POINTER_DELTA)) -const struct bpf_struct_ops *bpf_struct_ops_find(u32 type_id); +const struct bpf_struct_ops_desc *bpf_struct_ops_find(u32 type_id); void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log); bool bpf_struct_ops_get(const void *kdata); void bpf_struct_ops_put(const void *kdata); @@ -1736,7 +1741,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr); #endif #else -static inline const struct bpf_struct_ops *bpf_struct_ops_find(u32 type_id) +static inline const struct bpf_struct_ops_desc *bpf_struct_ops_find(u32 type_id) { return NULL; } diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c index 9f95e9fc00f3..5fbf88e6f4e5 100644 --- a/kernel/bpf/bpf_struct_ops.c +++ b/kernel/bpf/bpf_struct_ops.c @@ -32,7 +32,7 @@ struct bpf_struct_ops_value { struct bpf_struct_ops_map { struct bpf_map map; struct rcu_head rcu; - const struct bpf_struct_ops *st_ops; + const struct bpf_struct_ops_desc *st_ops_desc; /* protect map_update */ struct mutex lock; /* link has all the bpf_links that is populated @@ -92,9 +92,9 @@ enum { __NR_BPF_STRUCT_OPS_TYPE, }; -static struct bpf_struct_ops * const bpf_struct_ops[] = { +static struct bpf_struct_ops_desc bpf_struct_ops[] = { #define BPF_STRUCT_OPS_TYPE(_name) \ - [BPF_STRUCT_OPS_TYPE_##_name] = &bpf_##_name, + [BPF_STRUCT_OPS_TYPE_##_name] = { .st_ops = &bpf_##_name }, #include "bpf_struct_ops_types.h" #undef BPF_STRUCT_OPS_TYPE }; @@ -115,10 +115,11 @@ enum { IDX_MODULE_ID, }; -static void bpf_struct_ops_init_one(struct bpf_struct_ops *st_ops, - struct btf *btf, - struct bpf_verifier_log *log) +static void bpf_struct_ops_desc_init(struct bpf_struct_ops_desc *st_ops_desc, + struct btf *btf, + struct bpf_verifier_log *log) { + struct bpf_struct_ops *st_ops = st_ops_desc->st_ops; const struct btf_member *member; const struct btf_type *t; s32 type_id, value_id; @@ -190,18 +191,18 @@ static void bpf_struct_ops_init_one(struct bpf_struct_ops *st_ops, pr_warn("Error in init bpf_struct_ops %s\n", st_ops->name); } else { - st_ops->type_id = type_id; - st_ops->type = t; - st_ops->value_id = value_id; - st_ops->value_type = btf_type_by_id(btf, - value_id); + st_ops_desc->type_id = type_id; + st_ops_desc->type = t; + st_ops_desc->value_id = value_id; + st_ops_desc->value_type = btf_type_by_id(btf, + value_id); } } } void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) { - struct bpf_struct_ops *st_ops; + struct bpf_struct_ops_desc *st_ops_desc; u32 i; /* Ensure BTF type is emitted for "struct bpf_struct_ops_##_name" */ @@ -210,14 +211,14 @@ void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) #undef BPF_STRUCT_OPS_TYPE for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) { - st_ops = bpf_struct_ops[i]; - bpf_struct_ops_init_one(st_ops, btf, log); + st_ops_desc = &bpf_struct_ops[i]; + bpf_struct_ops_desc_init(st_ops_desc, btf, log); } } extern struct btf *btf_vmlinux; -static const struct bpf_struct_ops * +static const struct bpf_struct_ops_desc * bpf_struct_ops_find_value(u32 value_id) { unsigned int i; @@ -226,14 +227,14 @@ bpf_struct_ops_find_value(u32 value_id) return NULL; for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) { - if (bpf_struct_ops[i]->value_id == value_id) - return bpf_struct_ops[i]; + if (bpf_struct_ops[i].value_id == value_id) + return &bpf_struct_ops[i]; } return NULL; } -const struct bpf_struct_ops *bpf_struct_ops_find(u32 type_id) +const struct bpf_struct_ops_desc *bpf_struct_ops_find(u32 type_id) { unsigned int i; @@ -241,8 +242,8 @@ const struct bpf_struct_ops *bpf_struct_ops_find(u32 type_id) return NULL; for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) { - if (bpf_struct_ops[i]->type_id == type_id) - return bpf_struct_ops[i]; + if (bpf_struct_ops[i].type_id == type_id) + return &bpf_struct_ops[i]; } return NULL; @@ -302,7 +303,7 @@ static void *bpf_struct_ops_map_lookup_elem(struct bpf_map *map, void *key) static void bpf_struct_ops_map_put_progs(struct bpf_struct_ops_map *st_map) { - const struct btf_type *t = st_map->st_ops->type; + const struct btf_type *t = st_map->st_ops_desc->type; u32 i; for (i = 0; i < btf_type_vlen(t); i++) { @@ -383,11 +384,12 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, void *value, u64 flags) { struct bpf_struct_ops_map *st_map = (struct bpf_struct_ops_map *)map; - const struct bpf_struct_ops *st_ops = st_map->st_ops; + const struct bpf_struct_ops_desc *st_ops_desc = st_map->st_ops_desc; + const struct bpf_struct_ops *st_ops = st_ops_desc->st_ops; struct bpf_struct_ops_value *uvalue, *kvalue; const struct btf_type *module_type; const struct btf_member *member; - const struct btf_type *t = st_ops->type; + const struct btf_type *t = st_ops_desc->type; struct bpf_tramp_links *tlinks; void *udata, *kdata; int prog_fd, err; @@ -400,7 +402,7 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, if (*(u32 *)key != 0) return -E2BIG; - err = check_zero_holes(st_ops->value_type, value); + err = check_zero_holes(st_ops_desc->value_type, value); if (err) return err; @@ -493,7 +495,7 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, } if (prog->type != BPF_PROG_TYPE_STRUCT_OPS || - prog->aux->attach_btf_id != st_ops->type_id || + prog->aux->attach_btf_id != st_ops_desc->type_id || prog->expected_attach_type != i) { bpf_prog_put(prog); err = -EINVAL; @@ -588,7 +590,7 @@ static long bpf_struct_ops_map_delete_elem(struct bpf_map *map, void *key) BPF_STRUCT_OPS_STATE_TOBEFREE); switch (prev_state) { case BPF_STRUCT_OPS_STATE_INUSE: - st_map->st_ops->unreg(&st_map->kvalue.data); + st_map->st_ops_desc->st_ops->unreg(&st_map->kvalue.data); bpf_map_put(map); return 0; case BPF_STRUCT_OPS_STATE_TOBEFREE: @@ -669,22 +671,22 @@ static int bpf_struct_ops_map_alloc_check(union bpf_attr *attr) static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) { - const struct bpf_struct_ops *st_ops; + const struct bpf_struct_ops_desc *st_ops_desc; size_t st_map_size; 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) + st_ops_desc = bpf_struct_ops_find_value(attr->btf_vmlinux_value_type_id); + if (!st_ops_desc) return ERR_PTR(-ENOTSUPP); - vt = st_ops->value_type; + vt = st_ops_desc->value_type; if (attr->value_size != vt->size) return ERR_PTR(-EINVAL); - t = st_ops->type; + t = st_ops_desc->type; st_map_size = sizeof(*st_map) + /* kvalue stores the @@ -696,7 +698,7 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) if (!st_map) return ERR_PTR(-ENOMEM); - st_map->st_ops = st_ops; + st_map->st_ops_desc = st_ops_desc; map = &st_map->map; ret = bpf_jit_charge_modmem(PAGE_SIZE); @@ -733,8 +735,8 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) static u64 bpf_struct_ops_map_mem_usage(const struct bpf_map *map) { struct bpf_struct_ops_map *st_map = (struct bpf_struct_ops_map *)map; - const struct bpf_struct_ops *st_ops = st_map->st_ops; - const struct btf_type *vt = st_ops->value_type; + const struct bpf_struct_ops_desc *st_ops_desc = st_map->st_ops_desc; + const struct btf_type *vt = st_ops_desc->value_type; u64 usage; usage = sizeof(*st_map) + @@ -808,7 +810,7 @@ static void bpf_struct_ops_map_link_dealloc(struct bpf_link *link) /* st_link->map can be NULL if * bpf_struct_ops_link_create() fails to register. */ - st_map->st_ops->unreg(&st_map->kvalue.data); + st_map->st_ops_desc->st_ops->unreg(&st_map->kvalue.data); bpf_map_put(&st_map->map); } kfree(st_link); @@ -855,7 +857,7 @@ static int bpf_struct_ops_map_link_update(struct bpf_link *link, struct bpf_map if (!bpf_struct_ops_valid_to_reg(new_map)) return -EINVAL; - if (!st_map->st_ops->update) + if (!st_map->st_ops_desc->st_ops->update) return -EOPNOTSUPP; mutex_lock(&update_mutex); @@ -868,12 +870,12 @@ static int bpf_struct_ops_map_link_update(struct bpf_link *link, struct bpf_map old_st_map = container_of(old_map, struct bpf_struct_ops_map, map); /* The new and old struct_ops must be the same type. */ - if (st_map->st_ops != old_st_map->st_ops) { + if (st_map->st_ops_desc != old_st_map->st_ops_desc) { err = -EINVAL; goto err_out; } - err = st_map->st_ops->update(st_map->kvalue.data, old_st_map->kvalue.data); + err = st_map->st_ops_desc->st_ops->update(st_map->kvalue.data, old_st_map->kvalue.data); if (err) goto err_out; @@ -924,7 +926,7 @@ int bpf_struct_ops_link_create(union bpf_attr *attr) if (err) goto err_out; - err = st_map->st_ops->reg(st_map->kvalue.data); + err = st_map->st_ops_desc->st_ops->reg(st_map->kvalue.data); if (err) { bpf_link_cleanup(&link_primer); link = NULL; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 1863826a4ac3..bd52d7b318a5 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -20081,6 +20081,7 @@ static void print_verification_stats(struct bpf_verifier_env *env) static int check_struct_ops_btf_id(struct bpf_verifier_env *env) { const struct btf_type *t, *func_proto; + const struct bpf_struct_ops_desc *st_ops_desc; const struct bpf_struct_ops *st_ops; const struct btf_member *member; struct bpf_prog *prog = env->prog; @@ -20093,14 +20094,15 @@ static int check_struct_ops_btf_id(struct bpf_verifier_env *env) } btf_id = prog->aux->attach_btf_id; - st_ops = bpf_struct_ops_find(btf_id); - if (!st_ops) { + st_ops_desc = bpf_struct_ops_find(btf_id); + if (!st_ops_desc) { verbose(env, "attach_btf_id %u is not a supported struct\n", btf_id); return -ENOTSUPP; } + st_ops = st_ops_desc->st_ops; - t = st_ops->type; + t = st_ops_desc->type; member_idx = prog->expected_attach_type; if (member_idx >= btf_type_vlen(t)) { verbose(env, "attach to invalid member idx %u of struct %s\n", diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c index 2748f9d77b18..594a138a9d3e 100644 --- a/net/bpf/bpf_dummy_struct_ops.c +++ b/net/bpf/bpf_dummy_struct_ops.c @@ -17,6 +17,8 @@ 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) { @@ -85,9 +87,15 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, void *image = NULL; unsigned int op_idx; 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; @@ -142,6 +150,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, static int bpf_dummy_init(struct btf *btf) { + bpf_dummy_ops_btf = btf; return 0; } diff --git a/net/ipv4/bpf_tcp_ca.c b/net/ipv4/bpf_tcp_ca.c index c7bbd8f3c708..5bb56c9ad4e5 100644 --- a/net/ipv4/bpf_tcp_ca.c +++ b/net/ipv4/bpf_tcp_ca.c @@ -20,6 +20,7 @@ static u32 unsupported_ops[] = { static const struct btf_type *tcp_sock_type; static u32 tcp_sock_id, sock_id; +static const struct btf_type *tcp_congestion_ops_type; static int bpf_tcp_ca_init(struct btf *btf) { @@ -36,6 +37,11 @@ static int bpf_tcp_ca_init(struct btf *btf) tcp_sock_id = type_id; tcp_sock_type = btf_type_by_id(btf, tcp_sock_id); + type_id = btf_find_by_name_kind(btf, "tcp_congestion_ops", BTF_KIND_STRUCT); + if (type_id < 0) + return -EINVAL; + tcp_congestion_ops_type = btf_type_by_id(btf, type_id); + return 0; } @@ -149,7 +155,7 @@ static u32 prog_ops_moff(const struct bpf_prog *prog) u32 midx; midx = prog->expected_attach_type; - t = bpf_tcp_congestion_ops.type; + t = tcp_congestion_ops_type; m = &btf_type_member(t)[midx]; return __btf_member_bit_offset(t, m) / 8;