From patchwork Wed Oct 11 17:03:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daan De Meyer X-Patchwork-Id: 13417625 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B1E241204; Wed, 11 Oct 2023 17:03:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fr+XFdhh" Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20A6AB6; Wed, 11 Oct 2023 10:03:36 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id ffacd0b85a97d-32d3755214dso45110f8f.0; Wed, 11 Oct 2023 10:03:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1697043814; x=1697648614; 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=vUgLd6uCTGmXiwt74h6Tnr+Ni8w2bJDpoH4TYmPjHoc=; b=fr+XFdhhgmPCnSauOpRCiWIEuz709m/Spx4GGcC2W2Ow65ZaXcxDg8GZiS+H69qLaq qSXFIy7Z/0EDDWJ0xGVhulS82qT0RtRuLJUrp+plEo9e5Kr8zuvW0Kjujshh1v8EobZF n4U7dTSwXsuSInp9FqeEQcK+bfiHwjW7X4cW6uejJJaKjZtvsvjhIu/wHz3yIF21rr+j D18t8L7eHPqSoesAx8UIfyr21643x+ohwLa7tOgg6mUMlm70UQkNeRSlFLSOfgJ4cYnG v1BG9YQyfDjjiDwlYkxCcDJy1Lb7XUQVuWOLNvGv9UUGEjRHVq7+jCsPF+40JWd6X+E4 DeFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697043814; x=1697648614; 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=vUgLd6uCTGmXiwt74h6Tnr+Ni8w2bJDpoH4TYmPjHoc=; b=cyXFysfrdybenbpxDew7ZRKTLQpD3Nwkg7IeIRDoQ2Lr2FHWllAu/8QfgYoEccyEfs 954sDZiuDTsejDPLmfJ9SuI8i1lQrPUxubW8fJQgULRXVoUz99u/0sbXsidQIqEFTVaX RqKuRruL6ioB/flomTUvj+uMe4W6YYUiKCoXX4CFUulRMQqbL4/xCCO3MlYityhW+i1r bmyz/ceoVnUz7JxyXTPi1wPFOqcWrp23PLNfRRJwQhCqKGf5BzCsF1AREAf4vWLpLDqC 2fnvGTZC17ggJSUjkNJ564atL8v1JfDzceF0vsOwe/jSPWHDrzeXzi2hTfHPdDtjCPnf HUXw== X-Gm-Message-State: AOJu0Yz8VQ9YmLIw2tknaTwXyQGhwL8KH7pt0pkOe8Em0xgW6ZPZsQsX on8lXl0Lj99SaV2NQzPXrVZJx9EkNYmRudDQ X-Google-Smtp-Source: AGHT+IGtO2V1ViiGG8N0pHsSKBe3pL61bVX54DYAz22DGZAsTUsbX8/RMySs5MkoCt3y63J9HhQ6Lg== X-Received: by 2002:a5d:6a01:0:b0:317:727f:3bc7 with SMTP id m1-20020a5d6a01000000b00317727f3bc7mr18785975wru.17.1697043814224; Wed, 11 Oct 2023 10:03:34 -0700 (PDT) Received: from localhost.localdomain ([2a02:a03f:864b:8201:e534:34f4:1c34:8de7]) by smtp.googlemail.com with ESMTPSA id h28-20020adfa4dc000000b003296b913bbesm2335480wrb.12.2023.10.11.10.03.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Oct 2023 10:03:33 -0700 (PDT) From: Daan De Meyer To: bpf@vger.kernel.org Cc: Daan De Meyer , martin.lau@linux.dev, kernel-team@meta.com, netdev@vger.kernel.org Subject: [PATCH bpf-next v9 3/9] bpf: Add bpf_sock_addr_set_unix_addr() to allow writing unix sockaddr from bpf Date: Wed, 11 Oct 2023 19:03:13 +0200 Message-ID: <20231011170321.73950-5-daan.j.demeyer@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231011170321.73950-1-daan.j.demeyer@gmail.com> References: <20231011170321.73950-1-daan.j.demeyer@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net As prep for adding unix socket support to the cgroup sockaddr hooks, let's add a kfunc bpf_sock_addr_set_unix_addr() that allows modifying a sockaddr from bpf. While this is already possible for AF_INET and AF_INET6, we'll need this kfunc when we add unix socket support since modifying the address for those requires modifying both the address and the sockaddr length. Signed-off-by: Daan De Meyer --- kernel/bpf/btf.c | 1 + net/core/filter.c | 34 +++++++++++++++++++++++++++++++++- 2 files changed, 34 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 69101200c124..15d71d2986d3 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -7850,6 +7850,7 @@ static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type) case BPF_PROG_TYPE_SYSCALL: return BTF_KFUNC_HOOK_SYSCALL; case BPF_PROG_TYPE_CGROUP_SKB: + case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: return BTF_KFUNC_HOOK_CGROUP_SKB; case BPF_PROG_TYPE_SCHED_ACT: return BTF_KFUNC_HOOK_SCHED_ACT; diff --git a/net/core/filter.c b/net/core/filter.c index a094694899c9..bd1c42b28483 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -81,6 +81,7 @@ #include #include #include +#include static const struct bpf_func_proto * bpf_sk_base_func_proto(enum bpf_func_id func_id); @@ -11752,6 +11753,26 @@ __bpf_kfunc int bpf_dynptr_from_xdp(struct xdp_buff *xdp, u64 flags, return 0; } + +__bpf_kfunc int bpf_sock_addr_set_unix_addr(struct bpf_sock_addr_kern *sa_kern, + const u8 *addr, u32 addrlen__sz) +{ + struct sockaddr *sa = sa_kern->uaddr; + struct sockaddr_un *un; + + if (sa_kern->sk->sk_family != AF_UNIX) + return -EINVAL; + + /* We do not allow changing the address of unnamed unix sockets. */ + if (addrlen__sz == 0 || addrlen__sz > UNIX_PATH_MAX) + return -EINVAL; + + un = (struct sockaddr_un *)sa; + memcpy(un->sun_path, addr, addrlen__sz); + sa_kern->uaddrlen = offsetof(struct sockaddr_un, sun_path) + addrlen__sz; + + return 0; +} __diag_pop(); int bpf_dynptr_from_skb_rdonly(struct sk_buff *skb, u64 flags, @@ -11776,6 +11797,10 @@ BTF_SET8_START(bpf_kfunc_check_set_xdp) BTF_ID_FLAGS(func, bpf_dynptr_from_xdp) BTF_SET8_END(bpf_kfunc_check_set_xdp) +BTF_SET8_START(bpf_kfunc_check_set_sock_addr) +BTF_ID_FLAGS(func, bpf_sock_addr_set_unix_addr) +BTF_SET8_END(bpf_kfunc_check_set_sock_addr) + static const struct btf_kfunc_id_set bpf_kfunc_set_skb = { .owner = THIS_MODULE, .set = &bpf_kfunc_check_set_skb, @@ -11786,6 +11811,11 @@ static const struct btf_kfunc_id_set bpf_kfunc_set_xdp = { .set = &bpf_kfunc_check_set_xdp, }; +static const struct btf_kfunc_id_set bpf_kfunc_set_sock_addr = { + .owner = THIS_MODULE, + .set = &bpf_kfunc_check_set_sock_addr, +}; + static int __init bpf_kfunc_init(void) { int ret; @@ -11800,7 +11830,9 @@ static int __init bpf_kfunc_init(void) ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_XMIT, &bpf_kfunc_set_skb); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_SEG6LOCAL, &bpf_kfunc_set_skb); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_NETFILTER, &bpf_kfunc_set_skb); - return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp); + return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + &bpf_kfunc_set_sock_addr); } late_initcall(bpf_kfunc_init);