From patchwork Mon Nov 6 21:14:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nathan Chancellor X-Patchwork-Id: 13447487 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D63A02E639; Mon, 6 Nov 2023 21:14:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="F74yB8bJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6639CC433C8; Mon, 6 Nov 2023 21:14:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699305269; bh=yOk149MnqQ38qeZeV/4etw3iKo3CYD5n8FeZGzh/eFc=; h=From:Date:Subject:To:Cc:From; b=F74yB8bJbDjRxQPrWVBp0rcIBA/1CoKPsUPx+XDnqKASkuUkdBYoh37c6UvH0cKhX wIxHDWgXtlPaGXOi2W+s/3s/ethyy+T8dEhuh+3qTBw41Ih6QVQRtAjnj2XKSjEY3v 28EGdOEvc/f2W/zne9ZsmlPve6sIp/pDj7j79xv0CgxoQMQekl7+fUewO2yBJ0EmnJ qmShe+edLqsf1VPBmi7+UaDKjkj8NT+By+yBgfSQYVbL/ksvsb97pYZRYyDbtZWlyz DtLWQV/7wgITaX6YSQPJVjbAOFvL1oYPinGSTkqfFCxqBKYm3mkcWEKo42hx2iKgGv BS/6AeS9E4u9Q== From: Nathan Chancellor Date: Mon, 06 Nov 2023 14:14:16 -0700 Subject: [PATCH net v3] tcp: Fix -Wc23-extensions in tcp_options_write() Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231106-tcp-ao-fix-label-in-compound-statement-warning-v3-1-b54a64602a85@kernel.org> X-B4-Tracking: v=1; b=H4sIACdXSWUC/52OQQ6CMBBFr2K6dgwDCNSV9zAuShmgEaakragh3 N2GjXGpyz8/895fhCdnyIvTbhGOZuON5Riy/U7oXnFHYJqYRZqkGSYZQtATKAutecKgahrAMGg 7TvbODfigAo3EAR7KseEOqG4KLWVZ5bISETo5iq+b8CKYgrjGY298sO61jZhxq/71zQgIWpYZN ojHFsvzjRzTcLCu21xz+uFjUvzMTyNfIrVtQVjklf7ir+v6BkvB94tSAQAA To: edumazet@google.com, davem@davemloft.net, dsahern@kernel.org, kuba@kernel.org, pabeni@redhat.com Cc: ndesaulniers@google.com, trix@redhat.com, 0x7f454c46@gmail.com, noureddine@arista.com, hch@infradead.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, patches@lists.linux.dev, Nathan Chancellor X-Mailer: b4 0.13-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=4778; i=nathan@kernel.org; h=from:subject:message-id; bh=yOk149MnqQ38qeZeV/4etw3iKo3CYD5n8FeZGzh/eFc=; b=owGbwMvMwCEmm602sfCA1DTG02pJDKme4SaXfJoX3r0VsrR01445f1buSnbn39V4u66r97CQ1 Z/WybukOkpZGMQ4GGTFFFmqH6seNzScc5bxxqlJMHNYmUCGMHBxCsBEXhoyMrRMdQr09N8oPO8f j/P1DmaWLyskL7e/VMz67PNJdY7P/LsM/2wEWY5F8B9kWFs2qVvhvo/T68KqtuoNuzdnub/7lHO sgxUA X-Developer-Key: i=nathan@kernel.org; a=openpgp; fpr=2437CB76E544CB6AB3D9DFD399739260CB6CB716 X-Patchwork-Delegate: kuba@kernel.org Clang warns (or errors with CONFIG_WERROR=y) when CONFIG_TCP_AO is set: net/ipv4/tcp_output.c:663:2: error: label at end of compound statement is a C23 extension [-Werror,-Wc23-extensions] 663 | } | ^ 1 error generated. On earlier releases (such as clang-11, the current minimum supported version for building the kernel) that do not support C23, this was a hard error unconditionally: net/ipv4/tcp_output.c:663:2: error: expected statement } ^ 1 error generated. While adding a semicolon after the label would resolve this, it is more in line with the kernel as a whole to refactor this block into a standalone function, which means the goto a label construct can just be replaced with a return statement. Do so to resolve the warning. Closes: https://github.com/ClangBuiltLinux/linux/issues/1953 Fixes: 1e03d32bea8e ("net/tcp: Add TCP-AO sign to outgoing packets") Signed-off-by: Nathan Chancellor Reviewed-by: Dmitry Safonov Reviewed-by: Eric Dumazet --- Changes in v3: - Don't use a pointer to a pointer for ptr parameter to avoid the extra indirection in process_tcp_ao_options(), just return the modified ptr value back to the caller (Eric) - Link to v2: https://lore.kernel.org/r/20231106-tcp-ao-fix-label-in-compound-statement-warning-v2-1-91eff6e1648c@kernel.org Changes in v2: - Break out problematic block into its own function so that goto can be replaced with a simple return, instead of the simple semicolon approach of v1 (Christoph) - Link to v1: https://lore.kernel.org/r/20231031-tcp-ao-fix-label-in-compound-statement-warning-v1-1-c9731d115f17@kernel.org --- net/ipv4/tcp_output.c | 70 ++++++++++++++++++++++++++++----------------------- 1 file changed, 39 insertions(+), 31 deletions(-) --- base-commit: c1ed833e0b3b7b9edc82b97b73b2a8a10ceab241 change-id: 20231031-tcp-ao-fix-label-in-compound-statement-warning-ebd6c9978498 Best regards, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 0d8dd5b7e2e5..eb13a55d660c 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -601,6 +601,44 @@ static void bpf_skops_write_hdr_opt(struct sock *sk, struct sk_buff *skb, } #endif +static __be32 *process_tcp_ao_options(struct tcp_sock *tp, + const struct tcp_request_sock *tcprsk, + struct tcp_out_options *opts, + struct tcp_key *key, __be32 *ptr) +{ +#ifdef CONFIG_TCP_AO + u8 maclen = tcp_ao_maclen(key->ao_key); + + if (tcprsk) { + u8 aolen = maclen + sizeof(struct tcp_ao_hdr); + + *ptr++ = htonl((TCPOPT_AO << 24) | (aolen << 16) | + (tcprsk->ao_keyid << 8) | + (tcprsk->ao_rcv_next)); + } else { + struct tcp_ao_key *rnext_key; + struct tcp_ao_info *ao_info; + + ao_info = rcu_dereference_check(tp->ao_info, + lockdep_sock_is_held(&tp->inet_conn.icsk_inet.sk)); + rnext_key = READ_ONCE(ao_info->rnext_key); + if (WARN_ON_ONCE(!rnext_key)) + return ptr; + *ptr++ = htonl((TCPOPT_AO << 24) | + (tcp_ao_len(key->ao_key) << 16) | + (key->ao_key->sndid << 8) | + (rnext_key->rcvid)); + } + opts->hash_location = (__u8 *)ptr; + ptr += maclen / sizeof(*ptr); + if (unlikely(maclen % sizeof(*ptr))) { + memset(ptr, TCPOPT_NOP, sizeof(*ptr)); + ptr++; + } +#endif + return ptr; +} + /* Write previously computed TCP options to the packet. * * Beware: Something in the Internet is very sensitive to the ordering of @@ -629,37 +667,7 @@ static void tcp_options_write(struct tcphdr *th, struct tcp_sock *tp, opts->hash_location = (__u8 *)ptr; ptr += 4; } else if (tcp_key_is_ao(key)) { -#ifdef CONFIG_TCP_AO - u8 maclen = tcp_ao_maclen(key->ao_key); - - if (tcprsk) { - u8 aolen = maclen + sizeof(struct tcp_ao_hdr); - - *ptr++ = htonl((TCPOPT_AO << 24) | (aolen << 16) | - (tcprsk->ao_keyid << 8) | - (tcprsk->ao_rcv_next)); - } else { - struct tcp_ao_key *rnext_key; - struct tcp_ao_info *ao_info; - - ao_info = rcu_dereference_check(tp->ao_info, - lockdep_sock_is_held(&tp->inet_conn.icsk_inet.sk)); - rnext_key = READ_ONCE(ao_info->rnext_key); - if (WARN_ON_ONCE(!rnext_key)) - goto out_ao; - *ptr++ = htonl((TCPOPT_AO << 24) | - (tcp_ao_len(key->ao_key) << 16) | - (key->ao_key->sndid << 8) | - (rnext_key->rcvid)); - } - opts->hash_location = (__u8 *)ptr; - ptr += maclen / sizeof(*ptr); - if (unlikely(maclen % sizeof(*ptr))) { - memset(ptr, TCPOPT_NOP, sizeof(*ptr)); - ptr++; - } -out_ao: -#endif + ptr = process_tcp_ao_options(tp, tcprsk, opts, key, ptr); } if (unlikely(opts->mss)) { *ptr++ = htonl((TCPOPT_MSS << 24) |