[{"id":3679185,"web_url":"http://patchwork.ozlabs.org/comment/3679185/","msgid":"","list_archive_url":null,"date":"2026-04-20T02:43:21","subject":"Re: [PATCH] ksmbd: fix O(N^2) DoS in smb2_lock via unbounded\n LockCount","submitter":{"id":79386,"url":"http://patchwork.ozlabs.org/api/people/79386/","name":"Namjae Jeon","email":"linkinjeon@kernel.org"},"content":"On Sun, Apr 19, 2026 at 12:45 AM Akif Sait wrote:\n>\n> smb2_lock() performs O(N^2) conflict detection with no cap on LockCount.\n> Cap lock_count at 64 to prevent CPU exhaustion from a single request.\n>\n> Signed-off-by: Akif Sait \nApplied it to #ksmbd-for-next-next.\nThanks!","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=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=XAueMNoq;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c15:e001:75::12fc:5321; helo=sin.lore.kernel.org;\n envelope-from=linux-cifs+bounces-10922-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=\"XAueMNoq\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=10.30.226.201"],"Received":["from sin.lore.kernel.org (sin.lore.kernel.org\n [IPv6:2600:3c15:e001:75::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 4fzVDG1VVsz1yGt\n\tfor ; Mon, 20 Apr 2026 12:43:42 +1000 (AEST)","from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sin.lore.kernel.org (Postfix) with ESMTP id 5C1943001187\n\tfor ; Mon, 20 Apr 2026 02:43:39 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id D931337B41B;\n\tMon, 20 Apr 2026 02:43:36 +0000 (UTC)","from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org\n [10.30.226.201])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id B65DB37A493\n\tfor ; Mon, 20 Apr 2026 02:43:36 +0000 (UTC)","by smtp.kernel.org (Postfix) with ESMTPSA id 5FD1EC2BCB6\n\tfor ; Mon, 20 Apr 2026 02:43:36 +0000 (UTC)","by mail-ed1-f53.google.com with SMTP id\n 4fb4d7f45d1cf-6745a88eec7so2640344a12.2\n for ;\n Sun, 19 Apr 2026 19:43:36 -0700 (PDT)"],"ARC-Seal":"i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1776653016; cv=none;\n b=lRqzyXyL1/HPAT2eNzRIVtokOynZ2uhhZ5p/zFh2ILBGqgvJ7Sd6HFLMAb+L11zlH4VRS8Q4swGeIhSGHN4+Yc5IQJ9hQMNID3keApabDS8GYOdI8EoCx+A2MjLPmaUKr1O1tBm28rROiesXjskQiV6X7xnSHSIMgYUywT80py8=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1776653016; c=relaxed/simple;\n\tbh=WaSNSKptb0I9vrNt7rpWvx92RantJMFh+Ft0+wl1Wi8=;\n\th=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject:\n\t To:Cc:Content-Type;\n b=C41wdIopLla0U7+K1c5QPi9E/esUh7mOUimbJFtWeJRJUlFoovKJ0G4jg79LkMmDsBAKuWcF4EHlDSyXPJHGeqDz2OtXhyqR5fAJzrYgFzf3pwsjbFNsI5Wcfway8hbHVBsKuxHI5dfpM5ocj9/lFK6+RCijvad+GYd3XLYHrvY=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=XAueMNoq; arc=none smtp.client-ip=10.30.226.201","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1776653016;\n\tbh=WaSNSKptb0I9vrNt7rpWvx92RantJMFh+Ft0+wl1Wi8=;\n\th=References:In-Reply-To:From:Date:Subject:To:Cc:From;\n\tb=XAueMNoqfofEp+tCuHW53CiGi0o4VOAx/nHf+eTaIUzs/2inO7m8D4GvRqzjZZS4o\n\t WkI28cqUFJwN85Ff44Qq5Azfw2givEkfhnc5i2n8rBblqiCnYljrcxapGbpVq+szcM\n\t wZEilwbRgO3GZVUxmLjCRqYZYO2i0444oHv1l684CXzxFsAU7gR+8vy/pmSvpr4lX0\n\t TTWccyLNu5219kMr2c57wYvlETRl7V/yCJpS58ZFssrQm285FfPs7LcD4GuD/9uapn\n\t gz8IKAVFCpIgjqvKg6KYBpeWVLDV8SSyTbXgEfaBfsbFFvMUK9eklW8G0Ri8VAwec5\n\t igKSq9Tk+FuGQ==","X-Forwarded-Encrypted":"i=1;\n AFNElJ8FueNSzhph/80yrU3rR5phSsic8a3etlaYlAzY6KEOJQx9Y94rPlOe+xzhX9Gu22bGyPGZ3lH80WRY@vger.kernel.org","X-Gm-Message-State":"AOJu0YwIWtIR9+w173770UsifJSPqpuhfltYxwc54v0cKNRhfZOLuqpL\n\tnQU0+IlIsKdaxRVDCND6UJKvNojHYSjx7mzn7ThzGfjlkuXa7ltjowNEOFuySLmcLE+Xi4PWaR6\n\t9IwN15rrbD+ZCHRj9wn2v+RR1LB0zf9g=","X-Received":"by 2002:a05:6402:2790:b0:671:4f9a:9e4e with SMTP id\n 4fb4d7f45d1cf-672bfed76b7mr5069100a12.24.1776653014895; Sun, 19 Apr 2026\n 19:43:34 -0700 (PDT)","Precedence":"bulk","X-Mailing-List":"linux-cifs@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","References":"<20260418154505.84684-1-akif.sait111@gmail.com>","In-Reply-To":"<20260418154505.84684-1-akif.sait111@gmail.com>","From":"Namjae Jeon ","Date":"Mon, 20 Apr 2026 11:43:21 +0900","X-Gmail-Original-Message-ID":"\n ","X-Gm-Features":"AQROBzBtm-QdPZZ6AnaUF0KvC5f6-Pr_QcC5ksNo2zN3urRiuatJztROpFE_Zc4","Message-ID":"\n ","Subject":"Re: [PATCH] ksmbd: fix O(N^2) DoS in smb2_lock via unbounded\n LockCount","To":"Akif Sait ","Cc":"smfrench@gmail.com, senozhatsky@chromium.org, tom@talpey.com,\n\tlinux-cifs@vger.kernel.org","Content-Type":"text/plain; charset=\"UTF-8\"","Content-Transfer-Encoding":"quoted-printable"}}]