From patchwork Fri Jul 14 14:20:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Protopopov X-Patchwork-Id: 703055 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 965EFC001DC for ; Fri, 14 Jul 2023 14:20:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235601AbjGNOUN (ORCPT ); Fri, 14 Jul 2023 10:20:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235460AbjGNOUM (ORCPT ); Fri, 14 Jul 2023 10:20:12 -0400 Received: from mail-ej1-x636.google.com (mail-ej1-x636.google.com [IPv6:2a00:1450:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 29F1635B8 for ; Fri, 14 Jul 2023 07:19:59 -0700 (PDT) Received: by mail-ej1-x636.google.com with SMTP id a640c23a62f3a-99454855de1so48939966b.2 for ; Fri, 14 Jul 2023 07:19:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isovalent.com; s=google; t=1689344397; x=1691936397; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=8qk8T3EVPKdRYf+naU4m+YVtLzpGUKvj2gEOLRZFi7k=; b=fZmmnLinrKMYrKhEK0Ja70FkcaLdJD7wwVXadLH0V3hRFzduwn6n00RysF14lvageo JsAppEggMr42ZWN1aLrpKNzo2qv5GGcBc/1Y/Bp9px2acb1JlEkaYeBmKIbg1OH0tCU3 nECSVyAnpJZ+Ckza0WyWUMs9e7sQ4oz/c7ccFxMH+P1oM85hBV9vtxQGuvFE6kD5lYwf LzO0QciKwgQiKxGjFF2BIeujLoqdIgYuF5SU0iXUABihsf7b8YonSsL7LI1mgQ9XEaGq ZAYTaYQ0qsTJILqkKDA7KIw0ZURDZWhHWAqveJQMjOJbqQDsRC0q55gW+99LAHgoFVQD rg1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689344397; x=1691936397; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8qk8T3EVPKdRYf+naU4m+YVtLzpGUKvj2gEOLRZFi7k=; b=hFmpe0CxYaYB9LhKQzTrx495VqELUTGcvIkhdTNp9QsxFfDI+1eaggFdaw8Q6KoCsg rjrzevfksQDQ6pOx8o8zFx2GNOkuURbU4UQI0jhrYZAeWaucSH7rO/87bT3FMGl9JHnp Bh/Zxg3bzqNYN6/BWEAdJBviHqzfrAwKBNXdzdZym1LFr6Y+zJjbtjSXm3rjxdg6QY8e oFzJFl/NnXGgbVOCMqfTG8rUaR08HI3xJ12xOMrw9XaB6aI0Wzkye5UF3RDUEsWUxsvh bWc36eP3NPzqSaVeuZjKXt87PUoVCIeo3zJnsUXC4AiXHOhOQX8bxfgA+8gncH3ncQTC WwoQ== X-Gm-Message-State: ABy/qLYW5p+GCqxKKfjp8AndvSVSURmhAOn/G1xrCA1d37G731ZIboad H/B4VOCHOX4SMvV7kg6sFBGnQg== X-Google-Smtp-Source: APBJJlE3dUHsS60CUNmtFflD35N+5SzU2TRu3lWZvljtOkzKkJCtJygfCLn+Ia0YaPigbhKdj9mlEQ== X-Received: by 2002:a17:906:9146:b0:989:450:e585 with SMTP id y6-20020a170906914600b009890450e585mr3728345ejw.45.1689344397549; Fri, 14 Jul 2023 07:19:57 -0700 (PDT) Received: from zh-lab-node-5.home ([2a02:168:f656:0:1ac0:4dff:fe0f:3782]) by smtp.gmail.com with ESMTPSA id n11-20020a1709061d0b00b00982cfe1fe5dsm5469294ejh.65.2023.07.14.07.19.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Jul 2023 07:19:57 -0700 (PDT) From: Anton Protopopov To: Martin KaFai Lau , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Mykola Lysenko , Shuah Khan , Hou Tao , Joe Stringer , Anton Protopopov , bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next 1/3] bpf: consider CONST_PTR_TO_MAP as trusted pointer to struct bpf_map Date: Fri, 14 Jul 2023 14:20:58 +0000 Message-Id: <20230714142100.42265-2-aspsk@isovalent.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230714142100.42265-1-aspsk@isovalent.com> References: <20230714141747.41560-1-aspsk@isovalent.com> <20230714142100.42265-1-aspsk@isovalent.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Patch verifier to regard values of type CONST_PTR_TO_MAP as trusted pointers to struct bpf_map. This allows kfuncs to work with `struct bpf_map *` arguments. Save some bytes by defining btf_bpf_map_id as BTF_ID_LIST_GLOBAL_SINGLE (which is u32[1]), not as BTF_ID_LIST (which is u32[64]). Signed-off-by: Anton Protopopov --- include/linux/btf_ids.h | 1 + kernel/bpf/map_iter.c | 3 +-- kernel/bpf/verifier.c | 5 ++++- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index 00950cc03bff..a3462a9b8e18 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -267,5 +267,6 @@ MAX_BTF_TRACING_TYPE, extern u32 btf_tracing_ids[]; extern u32 bpf_cgroup_btf_id[]; extern u32 bpf_local_storage_map_btf_id[]; +extern u32 btf_bpf_map_id[]; #endif diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c index d06d3b7150e5..b67996147895 100644 --- a/kernel/bpf/map_iter.c +++ b/kernel/bpf/map_iter.c @@ -78,8 +78,7 @@ static const struct seq_operations bpf_map_seq_ops = { .show = bpf_map_seq_show, }; -BTF_ID_LIST(btf_bpf_map_id) -BTF_ID(struct, 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, diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 0b9da95331d7..5663f97ef292 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5419,6 +5419,9 @@ static bool is_trusted_reg(const struct bpf_reg_state *reg) if (reg->ref_obj_id) return true; + if (reg->type == CONST_PTR_TO_MAP) + return true; + /* If a register is not referenced, it is trusted if it has the * MEM_ALLOC or PTR_TRUSTED type modifiers, and no others. Some of the * other type modifiers may be safe, but we elect to take an opt-in @@ -10052,13 +10055,13 @@ static bool __btf_type_is_scalar_struct(struct bpf_verifier_env *env, return true; } - static u32 *reg2btf_ids[__BPF_REG_TYPE_MAX] = { #ifdef CONFIG_NET [PTR_TO_SOCKET] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK], [PTR_TO_SOCK_COMMON] = &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON], [PTR_TO_TCP_SOCK] = &btf_sock_ids[BTF_SOCK_TYPE_TCP], #endif + [CONST_PTR_TO_MAP] = btf_bpf_map_id, }; enum kfunc_ptr_arg_type {