From patchwork Fri Oct 6 07:44:57 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: 13411089 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 23D7E79C4; Fri, 6 Oct 2023 07:45:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="C3rIWcPB" Received: from mail-lf1-x12e.google.com (mail-lf1-x12e.google.com [IPv6:2a00:1450:4864:20::12e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0416DEB; Fri, 6 Oct 2023 00:45:52 -0700 (PDT) Received: by mail-lf1-x12e.google.com with SMTP id 2adb3069b0e04-50307759b65so2340664e87.0; Fri, 06 Oct 2023 00:45:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1696578350; x=1697183150; 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=C3rIWcPB0iO3/6yw3n5UcRyemNAHG/8YDWFhSgUN5cfKLrIEoEt6w95BU40MoXKdTq WSQ0Z5L1pEumT8hM+xDd6eUb7C/e/tQ8k2h62XStHZt9AAvmmsbACuh6ys/5p1dsMftX EvX39G2Oc2iZXHYqZKcc6za7jdVO3ZeevTpXCWoQRgKSn5reLDnO5FK3vCWcuKHtMwMt R8/Q+ONd8PgJffkUmx9raJfOcmzqMekXOVpOmaYWBqL7iyO4bIZqBi9Pf+D8XmFnTZaz WDqY6SNzD5zrBJhoyq0EWlcu9bmRDbTn7NXOwSLn0QLQmfmWpoYpUiLiw2GitXK2WJZa WoXQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696578350; x=1697183150; 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=f9fKq9/TaLO344Se9lBYTvza6QMEF8ZhluHuWcMxMXkGSjMxymBIc26nON2xcOE9k1 67UrVphi0uzy8AP3dZ/qCSPgdiDQe1GKTSD0hDf76O/KPVzudDXaRgY5v5a5mYxY/sps anaD5BCpets69IQHimalykHeniq+sU+M8OdLb31+TKVFWXQI6nyKfwAPnkibtPFjzNK4 I39r7311SWNgGb/7bgkfXdG4ZVMme3qO0gG/qVsz07AgyLwrj+DMMj4nfVQLopV2pK7P ulP4tfsyWL5/omCcPBjZeDTrTY4QtTy3t5N9v++DV6MO/TRE5VWfvRCzskBR2tTJNmES SPDA== X-Gm-Message-State: AOJu0YxV2V9qxBPMdAh7bKKzzUuIDX5GyrmGukhAGOW8Yd14QxvWu/yT F+zww55xnbjto5VVjU5tiB+6DbbKhHvGTBVZ X-Google-Smtp-Source: AGHT+IHnQZ7pEsqzAgk42brqQxPDw/IGn+IGLrtmaA0Djlv6opgyAdNxRbz0kJUtiwMPA+YSvC78iQ== X-Received: by 2002:a2e:7d07:0:b0:2bc:b88c:64ed with SMTP id y7-20020a2e7d07000000b002bcb88c64edmr6451511ljc.12.1696578349752; Fri, 06 Oct 2023 00:45:49 -0700 (PDT) Received: from localhost.localdomain ([2a02:a03f:864b:8201:e534:34f4:1c34:8de7]) by smtp.googlemail.com with ESMTPSA id k22-20020a7bc416000000b00404719b05b5sm3126888wmi.27.2023.10.06.00.45.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Oct 2023 00:45:49 -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: Fri, 6 Oct 2023 09:44:57 +0200 Message-ID: <20231006074530.892825-4-daan.j.demeyer@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231006074530.892825-1-daan.j.demeyer@gmail.com> References: <20231006074530.892825-1-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);