{"id":2224126,"url":"http://patchwork.ozlabs.org/api/patches/2224126/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-cifs-client/patch/20260416211735.3558718-1-charsyam@gmail.com/","project":{"id":12,"url":"http://patchwork.ozlabs.org/api/projects/12/?format=json","name":"Linux CIFS Client","link_name":"linux-cifs-client","list_id":"linux-cifs.vger.kernel.org","list_email":"linux-cifs@vger.kernel.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260416211735.3558718-1-charsyam@gmail.com>","list_archive_url":null,"date":"2026-04-16T21:17:35","name":"smb: server: fix max_connections off-by-one in tcp accept path","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"7bfbec8bc3762d976f423ae88398217ac17e2c94","submitter":{"id":93166,"url":"http://patchwork.ozlabs.org/api/people/93166/?format=json","name":"CharSyam","email":"charsyam@gmail.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linux-cifs-client/patch/20260416211735.3558718-1-charsyam@gmail.com/mbox/","series":[{"id":500207,"url":"http://patchwork.ozlabs.org/api/series/500207/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-cifs-client/list/?series=500207","date":"2026-04-16T21:17:35","name":"smb: server: fix max_connections off-by-one in tcp accept path","version":1,"mbox":"http://patchwork.ozlabs.org/series/500207/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2224126/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2224126/checks/","tags":{},"related":[],"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-cifs@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=q70FK54Y;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c09:e001:a7::12fc:5321; helo=sto.lore.kernel.org;\n envelope-from=linux-cifs+bounces-10874-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com\n header.b=\"q70FK54Y\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=209.85.210.180","smtp.subspace.kernel.org;\n dmarc=pass (p=none dis=none) header.from=gmail.com","smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=gmail.com"],"Received":["from sto.lore.kernel.org (sto.lore.kernel.org\n [IPv6:2600:3c09:e001:a7::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fxW7f6qkYz1yD3\n\tfor ; Fri, 17 Apr 2026 07:17:50 +1000 (AEST)","from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sto.lore.kernel.org (Postfix) with ESMTP id 4FE523016515\n\tfor ; Thu, 16 Apr 2026 21:17:47 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 8B7E2372EE2;\n\tThu, 16 Apr 2026 21:17:45 +0000 (UTC)","from mail-pf1-f180.google.com (mail-pf1-f180.google.com\n [209.85.210.180])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id 53519373C04\n\tfor ; Thu, 16 Apr 2026 21:17:44 +0000 (UTC)","by mail-pf1-f180.google.com with SMTP id\n d2e1a72fcca58-8296e257735so4622b3a.1\n for ;\n Thu, 16 Apr 2026 14:17:44 -0700 (PDT)","from ser8.. 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For\nexample:\n\n- max_connections=1 rejects the first connection\n- max_connections=2 allows only one connection\n\nThe per-IP limit in the same function uses <= correctly because it\ncounts only pre-existing connections. The global limit instead checks\nthe post-increment total, so it should reject only when that total\nexceeds the configured maximum.\n\nFix this by changing the comparison from >= to >, so exactly\nmax_connections simultaneous connections are allowed and the next one\nis rejected. This matches the documented meaning of max_connections\nin fs/smb/server/ksmbd_netlink.h as the \"Number of maximum simultaneous\nconnections\".\n\nFixes: 0d0d4680db22 (\"ksmbd: add max connections parameter\")\nCc: stable@vger.kernel.org\nSigned-off-by: DaeMyung Kang \n---\n fs/smb/server/transport_tcp.c | 2 +-\n 1 file changed, 1 insertion(+), 1 deletion(-)","diff":"diff --git a/fs/smb/server/transport_tcp.c b/fs/smb/server/transport_tcp.c\nindex 7e29b06820e2..5e85341698c7 100644\n--- a/fs/smb/server/transport_tcp.c\n+++ b/fs/smb/server/transport_tcp.c\n@@ -279,7 +279,7 @@ static int ksmbd_kthread_fn(void *p)\n \n skip_max_ip_conns_limit:\n \t\tif (server_conf.max_connections &&\n-\t\t atomic_inc_return(&active_num_conn) >= server_conf.max_connections) {\n+\t\t atomic_inc_return(&active_num_conn) > server_conf.max_connections) {\n \t\t\tpr_info_ratelimited(\"Limit the maximum number of connections(%u)\\n\",\n \t\t\t\t\t atomic_read(&active_num_conn));\n \t\t\tatomic_dec(&active_num_conn);\n","prefixes":[]}