From patchwork Tue Sep 26 20:27:42 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: 13399672 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 C20BA4A553; Tue, 26 Sep 2023 20:28:14 +0000 (UTC) Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [IPv6:2a00:1450:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53CB013A; Tue, 26 Sep 2023 13:28:13 -0700 (PDT) Received: by mail-lj1-x229.google.com with SMTP id 38308e7fff4ca-2c16bc71e4cso60617821fa.0; Tue, 26 Sep 2023 13:28:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695760091; x=1696364891; 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=BstfFZI+kHKIEaZZ+H4hdhpYXYgW1vSYYhuyFZdMRU8=; b=fbNv+xHNOI23S1rhsKBMftVl00geZ6hA6giGMtXMVmAlvjVJF6CL+MfX2xbaJWUON0 ++Fb+FlpgFWg2e6FA4BomwHmIItkDYKYOlpOrof5Tc8tJoefqMnvCAGgCaNmmUlfOaca wbuNNknrSDFL5YC2BUuUfKo50kbJeZtb/Og+Xx+j/t3X4Wgu2mecz11JKe6iIgtgbR66 rXju9FMntaPZpTLdlGOarAvLJ29qm8hbK3V6tbUUrwHd0n7a/XJbj2KnK/RZVRxFtd3m XIFLpXLMqFJWxpd0uHEMN3wlphPKkiPmGWxVjr8HrAwT70euS9a5nxwsFMfIhDZLgHBl xIug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695760091; x=1696364891; 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=BstfFZI+kHKIEaZZ+H4hdhpYXYgW1vSYYhuyFZdMRU8=; b=SojxCSSlMogRirF9+bqLklFzBDAk4anN/hZb0iaD+MnV7ZpqUe7xGkVnjQ0fkHImAA ir1EehaX1p1AR/R4uTiAaPdZDPg/IaAljTZx3mO5RtFzjrx0lVQXE/zvX3LJR4NSowyB K4b1GhlGHqeA+ZCI4JkMgwd9zF0PcWcTWBoHIJKQIZ+ebBGQQ4k3pBgUkpcNE7o1paCC GIA5dYfcL1OJxcLFckWiFxQneP4AyhOi7JsQpiL38kFVzGrhFQFRyxjkIlIQ9hokJ6gL l928LzNGa+/EYdfv/yROR2kTJ1D9RfLeKgxivEP36SiZqW2O4TnxU+pv7YQs1JRcNTbw gAnA== X-Gm-Message-State: AOJu0YxuNnZU+Jak0MX29aQGW/zZYTtKEtXCVWO96kMnahbj8IqZz+R1 ynzZSvXQRAbv7kXsbZvmkNWt4UrTb5/OhlNW X-Google-Smtp-Source: AGHT+IErgBnnFYWSK+wT7VstOJ99vRjChMHWcupmtFAUoFI9q7ibVMLlt7EEw9TR7yDBc6IneGipKA== X-Received: by 2002:a2e:b60d:0:b0:2c1:7d85:73e3 with SMTP id r13-20020a2eb60d000000b002c17d8573e3mr98150ljn.49.1695760090741; Tue, 26 Sep 2023 13:28:10 -0700 (PDT) Received: from localhost.localdomain ([2a02:a03f:864b:8201:e534:34f4:1c34:8de7]) by smtp.googlemail.com with ESMTPSA id c19-20020a170906529300b00992e94bcfabsm8204664ejm.167.2023.09.26.13.28.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Sep 2023 13:28:10 -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 v6 3/9] bpf: Add bpf_sock_addr_set_unix_addr() to allow writing unix sockaddr from bpf Date: Tue, 26 Sep 2023 22:27:42 +0200 Message-ID: <20230926202753.1482200-4-daan.j.demeyer@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230926202753.1482200-1-daan.j.demeyer@gmail.com> References: <20230926202753.1482200-1-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_NONE,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 f93e835d90af..55765632059e 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);