From mboxrd@z Thu Jan 1 00:00:00 1970 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 0769B2877EA; Thu, 12 Feb 2026 05:32:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770874356; cv=none; b=NH33RIIl03O2sLIcYAo8yKcWXSMvZ/iI1i0yMeWrrf7Hp8fNTpwMCwuIxcTROJNKn74ppVLNzOBovTshAItTLWw97IliEOIRwmF0CLJNKJL3Fs349RAiy3VVvVkxXCliw5gsA9QB3a7eGvzjU9yzFzg5hMKtHHQzVmGFgiUyjpA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770874356; c=relaxed/simple; bh=GwpcvvAZ0c+F+p4CirK9eRn7hEIXOAm+mSqjiOX0OZA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eegHcUCVfbMZxZm2jNMTIbqITaqSCvm3umCyezDo3Tz5TPMXK9CsGlKUwJLi3mifqCQTbj/qjlcKWY3wIR3moPbxZPUWbiOOBEZaHw+NrYLUNaIEFMx2Tpj2E+pvl+UcW3pQMhy6Mzvrp21vJ+XPoduEUkqs6RM9l7uZZmcoEiQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=br+96d2J; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="br+96d2J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0CF47C19424; Thu, 12 Feb 2026 05:32:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770874355; bh=GwpcvvAZ0c+F+p4CirK9eRn7hEIXOAm+mSqjiOX0OZA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=br+96d2JVcgBlJi6iQq6j2cibI+Fz7yyQnItRRP9+Hm/OzpsgkrWg9aFGhx15/Gq+ 2cAwJ//+fc6ngVnj/W063w1n44DBRpM/d97Q4XLQ6YMnclndsugNg4zt5Wf73OXu8K caRU8ueYdeIAAeMnOCteFeXEvEvKR8fWCqXXzSXo3m9kI4UlH4EOFax9mHI36fPIY7 L9/huzZOoTfho2uK9UQM88JaCEr+X9Kc3XhjYrqN7lGCTT/1i8z56LUmSvMI/udhi1 Qe7Q+pIVnrAiqNuZeyQsYoiRqfQZ2qf636uqlGgkZoLNFdHgJwsWxTCXSP2XfCZWWe 9+JlRXhk4TQ6Q== From: Allison Henderson To: netdev@vger.kernel.org Cc: linux-kselftest@vger.kernel.org, pabeni@redhat.com, edumazet@google.com, rds-devel@oss.oracle.com, kuba@kernel.org, horms@kernel.org, linux-rdma@vger.kernel.org, allison.henderson@oracle.com Subject: [PATCH net-next v4 4/4] net/rds: Use proper peer port number even when not connected Date: Wed, 11 Feb 2026 22:32:30 -0700 Message-ID: <20260212053230.1921241-5-achender@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260212053230.1921241-1-achender@kernel.org> References: <20260212053230.1921241-1-achender@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Greg Jumper The function rds_tcp_get_peer_sport() should return the peer port of a socket, even when the socket is not currently connected, so that RDS can reliably determine the MPRDS "lane" corresponding to the port. rds_tcp_get_peer_sport() calls kernel_getpeername() to get the port number; however, when paths between endpoints frequently drop and reconnect, kernel_getpeername() can return -ENOTCONN, causing rds_tcp_get_peer_sport() to return an error, and ultimately causing RDS to use the wrong lane for a port when reconnecting to a peer. This patch modifies rds_tcp_get_peer_sport() to directly call the socket-specific get-name function (inet_getname() in this case) that kernel_getpeername() also calls. The socket-specific function offers an additional argument which, when set to a value greater than 1, causes the function to return the socket's peer name even when the socket is not connected, which in turn allows rds_tcp_get_peer_sport() to return the correct port number. Signed-off-by: Greg Jumper Signed-off-by: Allison Henderson --- net/rds/tcp_listen.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index f2c4778be0b3..ba283c8ffa64 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -67,7 +67,14 @@ rds_tcp_get_peer_sport(struct socket *sock) } saddr; int sport; - if (kernel_getpeername(sock, &saddr.addr) >= 0) { + /* Call the socket's getname() function (inet_getname() in this case) + * with a final argument greater than 1 to get the peer's port + * regardless of whether the socket is currently connected. + * Using peer=2 will get the peer port even during reconnection states + * (TCPF_CLOSE, TCPF_SYN_SENT). This avoids -ENOTCONN while + * inet_dport still contains the correct peer port. + */ + if (sock->ops->getname(sock, &saddr.addr, 2) >= 0) { switch (saddr.addr.sa_family) { case AF_INET: sport = ntohs(saddr.sin.sin_port); @@ -177,7 +184,7 @@ void rds_tcp_conn_slots_available(struct rds_connection *conn, bool fan_out) if (fan_out) /* Delegate fan-out to a background worker in order - * to allow "kernel_getpeername" to acquire a lock + * to allow "sock->ops->getname()" to acquire a lock * on the socket. * The socket is already locked in this context * by either "rds_tcp_recv_path" or "tcp_v{4,6}_rcv", -- 2.43.0