From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9CD4F35E1A3; Mon, 14 Sep 2026 03:37:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789357042; cv=none; b=RvgZuUOMj+w449PaSv2CP0FvB5tVkNsBkG3Buocsr+rPUT6Trlrow5U17hjBiLAcikeurbRyraVPrUqoc+PpMQk6WIbZD1HWQt7aQqQWjQk1dPzJ5XfBQG02eTV86vlBgEr5AaBo13afF2WKKyeCvsnFf+XBYnpcwgSH08U16uk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789357042; c=relaxed/simple; bh=l09qwOE5YR2ATkzO5c6FnO90asYtEnnucV6slikfzEI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=By+e9OfktbnEZZpfWAO5c8p+2MJsJkSl47+SL6UNj6BsJoMrPJq9Y/VLXA1q029ztj6t8yNXEJFNIQ5TzZmlpiRf083J9G5zSMGE8/DtOkLovCkonZgPLWwN8hy+Pt8nO5UuhmaWuoC3DycPVBr/KGzJrt+XnjBREdvwGFgEriA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bcvFXeuf; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bcvFXeuf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 001721F00893; Mon, 14 Sep 2026 03:37:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789357041; bh=YU42TL81YFZm7tgZvg285pKw+JqqFh9iFlBlrADUa8Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bcvFXeufLGz305UMcq5ZjRvPJMeL2V7omy7TnxVJ10qk+KfC0m7yQo8KIK4jUJGTP Kl29WREOJmpWFb+VX0zP9kiP+t1A7GxazBgGzSg2z1F1mKFxs3uuSN2B6C67KvthOr uCqVKVLCPlHhWE5VcMAmGrIXb4PvqB3VM5U1MEITIDlcT0OTH2jdo/peDPrZPObjzE ibRTbOrhydDgd3avpEIaZPqbYoJdb8FCiZW6GZgx51PzMlzv7rd2F4pkwbU7pUagcM 98dHK65yrDgeNG/h/ENOX23XwnPBOSCJVpFf+iXtxHXpMqb7xmzTa9HShKBhbovbRq B/lpEPh17v3QQ== From: Allison Henderson To: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, pabeni@redhat.com, edumazet@google.com, kuba@kernel.org, horms@kernel.org Cc: achender@kernel.org, nicoyip.dev@gmail.com Subject: [PATCH net-next v3 02/13] net/rds: free every path's transport data on the passive create paths Date: Sun, 13 Sep 2026 20:37:08 -0700 Message-Id: <20260914033719.138057-3-achender@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260914033719.138057-1-achender@kernel.org> References: <20260914033719.138057-1-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 trans->conn_alloc() may allocate transport data for every path of a multipath connection - rds_tcp_conn_alloc() does - which is why the lost-creation-race exit of __rds_conn_create() loops over all npaths when it frees the connection it just built. The passive-connection exit right above it, taken when a loopback parent already has its c_passive twin, frees only path 0 and leaks the transport data of paths 1..npaths-1. RDS/TCP loopback is exactly a multipath passive connection, so this is reachable. Move the loop into a helper and use it on both exits. Fixes: 1c5113cf796b ("RDS: Initialize all RDS_MPATH_WORKERS in __rds_conn_create") Assisted-by: Claude-Code:claude-fable-5 Signed-off-by: Allison Henderson --- net/rds/connection.c | 31 ++++++++++++++++++------------- 1 file changed, 18 insertions(+), 13 deletions(-) diff --git a/net/rds/connection.c b/net/rds/connection.c index b6c4beb50eaf..a96569a3ee9a 100644 --- a/net/rds/connection.c +++ b/net/rds/connection.c @@ -161,6 +161,22 @@ static void __rds_conn_path_init(struct rds_connection *conn, cp->cp_flags = 0; } +/* Undo trans->conn_alloc(): it may have allocated transport data for + * every path of a multipath connection, not just for path 0. + */ +static void rds_conn_free_transport_data(struct rds_connection *conn, + int npaths) +{ + struct rds_conn_path *cp; + int i; + + for (i = 0; i < npaths; i++) { + cp = &conn->c_path[i]; + if (cp->cp_transport_data) + conn->c_trans->conn_free(cp->cp_transport_data); + } +} + /* * There is only every one 'conn' for a given pair of addresses in the * system at a time. They contain messages to be retransmitted and so @@ -316,7 +332,7 @@ static struct rds_connection *__rds_conn_create(struct net *net, if (parent) { /* Creating passive conn */ if (parent->c_passive) { - trans->conn_free(conn->c_path[0].cp_transport_data); + rds_conn_free_transport_data(conn, npaths); free_cp = conn->c_path; kmem_cache_free(rds_conn_slab, conn); conn = parent->c_passive; @@ -332,18 +348,7 @@ static struct rds_connection *__rds_conn_create(struct net *net, found = rds_conn_lookup(net, head, laddr, faddr, trans, tos, dev_if); if (found) { - struct rds_conn_path *cp; - int i; - - for (i = 0; i < npaths; i++) { - cp = &conn->c_path[i]; - /* The ->conn_alloc invocation may have - * allocated resource for all paths, so all - * of them may have to be freed here. - */ - if (cp->cp_transport_data) - trans->conn_free(cp->cp_transport_data); - } + rds_conn_free_transport_data(conn, npaths); free_cp = conn->c_path; kmem_cache_free(rds_conn_slab, conn); conn = found; -- 2.25.1