From patchwork Tue Oct 3 09:30:17 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: 13407350 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 451F1FC01; Tue, 3 Oct 2023 09:30:45 +0000 (UTC) Received: from mail-ej1-x62c.google.com (mail-ej1-x62c.google.com [IPv6:2a00:1450:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8255D3; Tue, 3 Oct 2023 02:30:42 -0700 (PDT) Received: by mail-ej1-x62c.google.com with SMTP id a640c23a62f3a-9ae7383b7ecso903139666b.0; Tue, 03 Oct 2023 02:30:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1696325441; x=1696930241; 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=ifPDLePmmIWk1DdLu6OWK0gItTQA0jTCMoVJhFKKt/nmOCfXvi6gkoc01ZrCWiTod6 hpzO8h9njCqG7u8f6Vh87rLFnxp206v52ysHkBo9/7DT8X6rgzVtJXGeohsMJb/W26hn QKLRlEzBZ7+PdHmh6aACBh/+YcTjbecFQRlfeDEs+nm/wKx08+E+EAPxOlF9MH4sLjmw QzH55Abqg1LAM3vYLwAd6VqIK9AkWknMW8lsw0spZ31IJpI5u8DGeaNxzP3Ex8a8zTNn BcYpLsblmY3GI2fHtjkpVEF7HOaE8D3H2L13EaTL/L+s5PNdmCi03Eh5+uXZKst4Bh6a 7mWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696325441; x=1696930241; 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=cJFWNJTwPdCBPTBoVuNxsf/P/fFUfU2jK8xHHZhPpLq2oYYkeABSQwnKuCvA8bjd2e HE1/wr7nvVQ5QTdcBAeUSai5dJN91DNCdzjc0nrP53RGpjuPLZjzvHdfiB8TuHMlUyQG y6JD2Ek6us171tQrDMs6ILjSSV9BP4zesULzPrgcGYoOPEXEkRIG7ViQCYXhICAdzfii IkjfzgwSeminamqAfOD6dogcqo6lLng2f53Uf38kI5JkX0BR61hmKXKFjDySpH3lgb15 x4+Y5eHmn+bJfTN27HVVQzaZMAmctCAz73uDiI+RIQy1YNcjuHxtDyei9jgl7bppoXyy rCYQ== X-Gm-Message-State: AOJu0YysXUXtRMnT1IeIKskUd7emxWMZi0SqVnn4Ow+CA/OUJN2Q1N4M 5IyLF/2i+++VM2tHGEbY+DCcFVf4GLA1BJVI X-Google-Smtp-Source: AGHT+IGBEAyWF19atk3N7Wy9rUxR4geAHOdhd9Dqi4TfF2zB2/3nTWJw/uBDJv8U9R1qkWm8GLvk6A== X-Received: by 2002:a17:907:7758:b0:9b2:b15b:383d with SMTP id kx24-20020a170907775800b009b2b15b383dmr1836551ejc.11.1696325440754; Tue, 03 Oct 2023 02:30:40 -0700 (PDT) Received: from daandemeyer-fedora-PC1EV17T.thefacebook.com (2001-1c05-3310-3500-15f4-3ba0-176b-cb00.cable.dynamic.v6.ziggo.nl. [2001:1c05:3310:3500:15f4:3ba0:176b:cb00]) by smtp.googlemail.com with ESMTPSA id g5-20020a170906594500b0098f33157e7dsm749851ejr.82.2023.10.03.02.30.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Oct 2023 02:30:40 -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 v7 3/9] bpf: Add bpf_sock_addr_set_unix_addr() to allow writing unix sockaddr from bpf Date: Tue, 3 Oct 2023 11:30:17 +0200 Message-ID: <20231003093025.475450-4-daan.j.demeyer@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231003093025.475450-1-daan.j.demeyer@gmail.com> References: <20231003093025.475450-1-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);