From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f181.google.com (mail-pl1-f181.google.com [209.85.214.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7AEB917993 for ; Sat, 15 Nov 2025 14:48:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763218130; cv=none; b=eR1LPpf4+TuzJ1vqKbm+XTdizxI3mzeci6BhfgvETVpGpTndz6I7RR8mSO/RX3CieiVaB38vM5+JzLLRKssvWQ9d48qktpHxm1vam6tLwkeZ5emaTJpbfM9JAIomN2D4R46xhwe6IVN4PPZlx8rzLpGyascUtNESnUb4WcygAMo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763218130; c=relaxed/simple; bh=NZH79oJQrUr0+yLUGXyMSbz2UGtduLS0AKXdFUHNmfs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=caqFZRhFhr1bN6iFYA8I7FT2iNBJEqNEa8lm4vU8VsR/Bbj6DBgd4U7g0lSq/rqLvQAliVNR5Oi1IsZjPP+mgek7rr4SpQy1/OLBZ3yEakLAGEnOI5ZxwshStd0yfKfMZVfufZ53KyjX35u5vmmInQQntd/R2sKG0dPoZ817CRw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=BcTQ6xjT; arc=none smtp.client-ip=209.85.214.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="BcTQ6xjT" Received: by mail-pl1-f181.google.com with SMTP id d9443c01a7336-29800ac4ef3so6753355ad.1 for ; Sat, 15 Nov 2025 06:48:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1763218129; x=1763822929; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Eblm4oH8WMKHd2tfTsYGfp0Iegef7142gb8GNo8dgAM=; b=BcTQ6xjTMx83ipuCQjbXHesHqtNHc2mzHQcCsbJdroB3ZUkrHKKPnWumQk+TA/LnFe lQM/cW7NOCutIm7bGSk/yUigzvA22swD+MqHRtwaAPJfYZRrSUwam5Ta1omFpx59BXsW IdvEQHh5wZ4ULKMhFQEnFsMGnM4QoZvs9clcH8bR5UXlJ23Bvv94fXkG+1JwKoMaJIAz sZBUdbnanDHXn6L8N2459cLxJUSmLrW/WSEkP05bNZSM+xzz+IC4anFvC59XeksFOgDH ePuL2kHVr/vD9NPkY5cem4jHTlRfFBVNDhbZ89KFwhuZtYUopRghK8uGA7FYjkN+Qbj0 Nmkw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1763218129; x=1763822929; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=Eblm4oH8WMKHd2tfTsYGfp0Iegef7142gb8GNo8dgAM=; b=NP27rRFc+OAyoAklNmnz7vkRu5ggl1ly/8oDKPQXxqyDldmIUbet9Nzrr23EO+xSKn xFiWGWPNIFRijA7IX2ZnvnSRaO1WoJ54q8tFAqdtnitViGNoJEPTkIzO/eycJhYHVyRJ 0BnmztgiNa0ioLLcasnZ5DDzIYSSQqRe6jFEb2E2e1VyExvPQFiB2UzjxbXf5GDw5f45 gPBqr1xZafn4O8WHAluE+EF2khA1IbbC0BMT76kHYt+rWeZDD+KEQVHi5VnVNfRRYSCV olqCbWver1UIIyEA9FZovFBIbPZ6LqZ5EbcyWTln4vj2JcnXe+d2Mz4Qcs3eu4vLbPn2 rNzg== X-Forwarded-Encrypted: i=1; AJvYcCXXUO7UigwIG+sZdWiPnkkNE0zEztW6yf2CE/6bk0CZqaK3r29qiKS70dv/jkGyda2judtr2hTP8M9Z@vger.kernel.org X-Gm-Message-State: AOJu0YwUGLHcB9mQpNH3mBpn5IzG47aPtLiDey/MBC8xgpa+/dKcShJM CWJbivJvbSM0C7MMPqKabKXBpBdAMM4yW1Qg9TPX5fChtaCO4z8dMiY5 X-Gm-Gg: ASbGncvKXhe71R6L4s3li+sXbNjEv/HB9Pw7FhRfeavPfAjFNkJX5/tNVY8POyWGK4W TEQV/Swj9ZdBqq67z5BEydP2eXjs6MO8jI2oNXvA1M8XsarAD/95rhR967wYUMpRgDjNtw+gc8j /TFFDAuURIO1yI3iOksGj/afmfZGjFaRB3YaGxZQ4jzhqKChpy7/gsHVnbAfeu+V0Snba6WSscF WxgFe1VF9YeIz3+wz+x30FdeshObt5LGKHu13/EeCaDkGWx8fHEdq+cAVQFt6OCyrtY7z/0QwB7 vdqTU37R/Aw+TMQyOjOeVGfbJbS4rJnwfI/v5pa+NCuV18o5KqkkCj8Jmmt5tcRjh5oY7hSk0Tf rBk+F7pJ3pa3G9cnvmGGRfnPlXud4PCkcYooxVbFLU+DOqxMUFOGFzf0RlTzjRCjoJX3PaB8Y7V 65ABwXnbMI4hCcPVvBH9hFMmINa5r5R96Y6sO3y2eN83+CifwHpiTeQmAXQxxLnu2rMkcjcIvD6 arpNug457k= X-Google-Smtp-Source: AGHT+IEFPRicWDHAlwZaQ/FpL1TsXLtWQwGVzqmxdM7jo4UhyoPLcjUWPuif+VXkEX1VRD7+udJK9Q== X-Received: by 2002:a17:902:d483:b0:295:54cd:d2e2 with SMTP id d9443c01a7336-2986a5edceemr42293645ad.0.1763218128806; Sat, 15 Nov 2025 06:48:48 -0800 (PST) Received: from poi.localdomain (KD118158218050.ppp-bb.dion.ne.jp. [118.158.218.50]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2985c25a688sm88392485ad.49.2025.11.15.06.48.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 15 Nov 2025 06:48:48 -0800 (PST) From: Qianchang Zhao To: Namjae Jeon , Steve French Cc: gregkh@linuxfoundation.org, linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org, Zhitong Liu , Qianchang Zhao , stable@vger.kernel.org Subject: [PATCH v2] ksmbd: vfs_cache: avoid integer overflow in inode_hash() Date: Sat, 15 Nov 2025 23:48:36 +0900 Message-Id: <20251115144836.555128-1-pioooooooooip@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit inode_hash() currently mixes a hash value with the super_block pointer using an unbounded multiplication: tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) / L1_CACHE_BYTES; On 64-bit kernels this multiplication can overflow and wrap in unsigned long arithmetic. While this is not a memory-safety issue, it is an unbounded integer operation and weakens the mixing properties of the hash. Replace the pointer*hash multiply with hash_long() over a mixed value (hashval ^ (unsigned long)sb) and keep the existing shift/mask. This removes the overflow source and reuses the standard hash helper already used in other kernel code. This is an integer wraparound / robustness issue (CWE-190/CWE-407), not a memory-safety bug. Reported-by: Qianchang Zhao Reported-by: Zhitong Liu Cc: stable@vger.kernel.org Signed-off-by: Qianchang Zhao --- fs/smb/server/vfs_cache.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/fs/smb/server/vfs_cache.c b/fs/smb/server/vfs_cache.c index dfed6fce8..a62ea5aae 100644 --- a/fs/smb/server/vfs_cache.c +++ b/fs/smb/server/vfs_cache.c @@ -10,6 +10,7 @@ #include #include #include +#include #include "glob.h" #include "vfs_cache.h" @@ -65,12 +66,8 @@ static void fd_limit_close(void) static unsigned long inode_hash(struct super_block *sb, unsigned long hashval) { - unsigned long tmp; - - tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) / - L1_CACHE_BYTES; - tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> inode_hash_shift); - return tmp & inode_hash_mask; + unsigned long mixed = hashval ^ (unsigned long)sb; + return hash_long(mixed, inode_hash_shift) & inode_hash_mask; } static struct ksmbd_inode *__ksmbd_inode_lookup(struct dentry *de) -- 2.34.1