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 B8A7838B121; Thu, 9 Apr 2026 17:34:15 +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=1775756055; cv=none; b=I/Kb0LLy6OYPvcF2JDsK7D67XRfWtDjZKNTvsnoHpwWt2XGOUFkqpxDhQqHGdX+53rZjCrvYOg4tHELIw9JBtWg1eGJmmQhwMbmilPnG1E3zBVMuvUEAD4gvIT8TWNvf2owtpzzRFkzSz/aNl/yoNGUOS4OGG7GKK9CkywuRSyM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775756055; c=relaxed/simple; bh=Ia3tPnC56tz9K91w3AqY0ZvMpakxHnNBSGZqH3L/LfI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=mKZvxoR9IUrALarMU/Ae793oVFBYvUWf3qZdRjmL6r+MY6zNoGy4+m1C/KyDA+7CppZeiYpAB/sTASBtB7HBgaJLeiy/2Vx60xYpaIhkXBAID9mngqzuhDgDctSBTAl/P/xGRWItA+4QY82u6xITfrCGDzomtTT7Zg/uH8UQk1Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eExgDLIf; 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="eExgDLIf" Received: by smtp.kernel.org (Postfix) with ESMTPS id 876CDC19424; Thu, 9 Apr 2026 17:34:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775756055; bh=Ia3tPnC56tz9K91w3AqY0ZvMpakxHnNBSGZqH3L/LfI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=eExgDLIfd+wK52tVCt5LiJvOafwVIQGLoqEwAMpcSxDyIirRhgyamjpb8AepoxF6c 4oIQmHBJbT26hvrw+d8YDQ+8/fXRd24Kq9xyFQMwGszxjm+ulzqu07BEtbKJc1FVyi DT3QAvkOjR7pppcdVyuEgopryhplfzSQIKNvZnnekfdzk7sMt4m/nrmiNLIvNZt4uc JFAecc1sNNEBcayE+uanTOQ46XSKC08y+3/EDu/8Lu6HImfQjwgU6V7xQNa1e259rQ AWpNYEV8VKo7iamOK1r2kGkY6Pnd/U+2GCIce0EuH5e0VAk4wEQARkKwwgbHK65DIW hRIYdz8vlPGyA== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73F45F364A8; Thu, 9 Apr 2026 17:34:15 +0000 (UTC) From: Manivannan Sadhasivam via B4 Relay Date: Thu, 09 Apr 2026 23:04:12 +0530 Subject: [PATCH v3 1/5] net: qrtr: ns: Limit the maximum server registration per node Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260409-qrtr-fix-v3-1-00a8a5ff2b51@oss.qualcomm.com> References: <20260409-qrtr-fix-v3-0-00a8a5ff2b51@oss.qualcomm.com> In-Reply-To: <20260409-qrtr-fix-v3-0-00a8a5ff2b51@oss.qualcomm.com> To: Manivannan Sadhasivam , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman Cc: linux-arm-msm@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Yiming Qian , Manivannan Sadhasivam X-Mailer: b4 0.15.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3040; i=manivannan.sadhasivam@oss.qualcomm.com; h=from:subject:message-id; bh=d3riliJXlMknVS54Ov71SzRRhSiv88e/lnkbjutnErI=; b=owEBbQGS/pANAwAKAVWfEeb+kc71AcsmYgBp1+MVcXh+sRzaqvD63YwBp28P4ftfPfsLheiHb LUTZbvABhOJATMEAAEKAB0WIQRnpUMqgUjL2KRYJ5dVnxHm/pHO9QUCadfjFQAKCRBVnxHm/pHO 9e50CACDAAC/duutxEw5WR7Rgnxv7rlmz6FkTIkBMA5bPOvogpnk56+qjp6ucuuxfwq3qaw3Hbg EO8dNGfLd4uASOWqTKROS4SPbQMLQTo86ySM/lITXO5Xad/CbB0SrIolF/O/Ov05HAqQyjovg13 PGuCfntmx8mTguW5a0HoOkvC5Mx9FJdkbmlCpMAn6Xa9NI38i+AgsJ1r80tbfxh7P1RB2I3YyFM otYELlbc0Im99x/maHYWK8hU1tr4DyouBaAZbuEDzqFPSJIt2RGGUti5dgdon/4dJJB+Y2N//X4 8n/2ojGnAIfkJkTOGjJpOkoZST+ovOmAy4wG9Q8uC0RStmu5 X-Developer-Key: i=manivannan.sadhasivam@oss.qualcomm.com; a=openpgp; fpr=C668AEC3C3188E4C611465E7488550E901166008 X-Endpoint-Received: by B4 Relay for manivannan.sadhasivam@oss.qualcomm.com/default with auth_id=461 X-Original-From: Manivannan Sadhasivam Reply-To: manivannan.sadhasivam@oss.qualcomm.com From: Manivannan Sadhasivam Current code does no bound checking on the number of servers added per node. A malicious client can flood NEW_SERVER messages and exhaust memory. Fix this issue by limiting the maximum number of server registrations to 256 per node. If the NEW_SERVER message is received for an old port, then don't restrict it as it will get replaced. While at it, also rate limit the error messages in the failure path of qrtr_ns_worker(). Note that the limit of 256 is chosen based on the current platform requirements. If requirement changes in the future, this limit can be increased. Cc: stable@vger.kernel.org Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace") Reported-by: Yiming Qian Reviewed-by: Simon Horman Signed-off-by: Manivannan Sadhasivam --- net/qrtr/ns.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c index 3203b2220860..63cb5861d87a 100644 --- a/net/qrtr/ns.c +++ b/net/qrtr/ns.c @@ -67,8 +67,14 @@ struct qrtr_server { struct qrtr_node { unsigned int id; struct xarray servers; + u32 server_count; }; +/* Max server limit is chosen based on the current platform requirements. If the + * requirement changes in the future, this value can be increased. + */ +#define QRTR_NS_MAX_SERVERS 256 + static struct qrtr_node *node_get(unsigned int node_id) { struct qrtr_node *node; @@ -229,6 +235,17 @@ static struct qrtr_server *server_add(unsigned int service, if (!service || !port) return NULL; + node = node_get(node_id); + if (!node) + return NULL; + + /* Make sure the new servers per port are capped at the maximum value */ + old = xa_load(&node->servers, port); + if (!old && node->server_count >= QRTR_NS_MAX_SERVERS) { + pr_err_ratelimited("QRTR client node %u exceeds max server limit!\n", node_id); + return NULL; + } + srv = kzalloc_obj(*srv); if (!srv) return NULL; @@ -238,10 +255,6 @@ static struct qrtr_server *server_add(unsigned int service, srv->node = node_id; srv->port = port; - node = node_get(node_id); - if (!node) - goto err; - /* Delete the old server on the same port */ old = xa_store(&node->servers, port, srv, GFP_KERNEL); if (old) { @@ -252,6 +265,8 @@ static struct qrtr_server *server_add(unsigned int service, } else { kfree(old); } + } else { + node->server_count++; } trace_qrtr_ns_server_add(srv->service, srv->instance, @@ -292,6 +307,7 @@ static int server_del(struct qrtr_node *node, unsigned int port, bool bcast) } kfree(srv); + node->server_count--; return 0; } @@ -670,7 +686,7 @@ static void qrtr_ns_worker(struct work_struct *work) } if (ret < 0) - pr_err("failed while handling packet from %d:%d", + pr_err_ratelimited("failed while handling packet from %d:%d", sq.sq_node, sq.sq_port); } -- 2.51.0