From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793830949; b=I/hmoUQz1OQUvTOs8CjN6sfDKq7iISM0Pe/cAEGmNc5MKsujLbkPR+8z3K0Z3Gg0q8l2 3gVxcuMftGLDOUBrlJZFQDjLPYKL3wsX/RB6Q2vyB8Dq8iCeRVRO01btgauah+l0dlOpU 0TElUwuEL1momhImi/9zfVDS7cF8iK39zpWaQrYvFPRIGkeB1jwzv8BcaPJkBMKJydu2N 8z8+sprytonBYdGsYGhH0NgB2LqMFXz4HAlvGAwd2MS94/PTtuoNsgdY0iurBR3jmoitE KA8ZvWUXf2XrDOi5H/gtWzgfY9OSJow7HuzhRbabsWarurtiF3Euu5uKLSv1uaBDhTw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793830949; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=7DpTd6eC5N5hl22DUOzPNYYIGND9aZXj5cWTgi20JbQ=; b=gonOIJoAR6h1izmqnPWzm2zm42lsF//UHbSj1ikSkh6jFAHh1lSZZHq9qM+2kK9tojM4 /rNDvHpoaTyMcHHMynlOfTji5/FzBogi+xW8uFGlFatmAS5ec/+G+SeT67dPJ57EvvQ0x GH+s5Gt/8j+mTxmYI/q7nlz8EZHlSG1UC0y8bg904lnWcYPwQmQXBHJFNCOrJZWNlnCkj wNXwJ713tOv9FTZi45crVKxmkh/G2L7o9pu+HH5VYh4Eeft2a4ExGarUQak1qcCClikwb n1CmpCK5vRWVOwNlhVxqJQTjXc46iHU5m0OTjdLIbyhA/tinJmtrxKpPcJKe6Rxr5QQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Si6Dd+MZ; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 21B60606A844; Wed, 4 Nov 2026 22:22:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Si6Dd+MZ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77C171F000C1; Wed, 4 Nov 2026 22:22:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793830948; bh=7DpTd6eC5N5hl22DUOzPNYYIGND9aZXj5cWTgi20JbQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Si6Dd+MZkE8+db2b7UpcMz4w0IyKWHwVfJDLAhIKVx9tg4X3jipsNGYHmBuY/JVVd 3g6DwmLcMqvpGFQvuF6Log4b6W7fZu4fjLGmVdBSwzgB9SGf6mLMQ9YUMd1kL1WDUG Blyhd2QpvKPUxMLbt3jRwy88R84GAlHftAoZYoUY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Namjae Jeon , Sasha Levin Subject: [PATCH 6.18 0417/1005] ksmbd: fix SMB2 byte-range lock end offset Date: Wed, 4 Nov 2026 16:02:30 -0500 Message-ID: <20261104211055.774253694@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Namjae Jeon [ Upstream commit 54d90311f9b4eb23f3b0b62650b0cfddb11a12ef ] SMB2 describes a byte-range lock using an offset and a length, while Linux file_lock uses an inclusive end offset. smb2_lock() currently sets fl_end to start + length and consequently locks one extra byte for every nonzero-length request. Translate nonzero lengths to start + length - 1 and reject ranges that cannot be represented by loff_t instead of silently truncating them at OFFSET_MAX. Track zero-length locks from the request length so one-byte ranges are not mistaken for zero-length locks after endpoint conversion. Signed-off-by: Namjae Jeon Signed-off-by: Sasha Levin --- fs/smb/server/smb2pdu.c | 44 +++++++++++++---------------------------- 1 file changed, 14 insertions(+), 30 deletions(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 16dea2c8b9267..fba9c75b9f878 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -7609,7 +7609,7 @@ static int smb2_set_flock_flags(struct file_lock *flock, int flags) } static struct ksmbd_lock *smb2_lock_init(struct file_lock *flock, - unsigned int cmd, int flags, + unsigned int cmd, int flags, bool zero_len, struct list_head *lock_list) { struct ksmbd_lock *lock; @@ -7623,8 +7623,7 @@ static struct ksmbd_lock *smb2_lock_init(struct file_lock *flock, lock->start = flock->fl_start; lock->end = flock->fl_end; lock->flags = flags; - if (lock->start == lock->end) - lock->zero_len = 1; + lock->zero_len = zero_len; INIT_LIST_HEAD(&lock->clist); INIT_LIST_HEAD(&lock->flist); INIT_LIST_HEAD(&lock->llist); @@ -7717,32 +7716,18 @@ int smb2_lock(struct ksmbd_work *work) lock_start = le64_to_cpu(lock_ele[i].Offset); lock_length = le64_to_cpu(lock_ele[i].Length); - if (lock_start > U64_MAX - lock_length) { + if (lock_start > OFFSET_MAX || + (lock_length && + lock_length - 1 > OFFSET_MAX - lock_start)) { pr_err("Invalid lock range requested\n"); rsp->hdr.Status = STATUS_INVALID_LOCK_RANGE; locks_free_lock(flock); goto out; } - if (lock_start > OFFSET_MAX) - flock->fl_start = OFFSET_MAX; - else - flock->fl_start = lock_start; - - lock_length = le64_to_cpu(lock_ele[i].Length); - if (lock_length > OFFSET_MAX - flock->fl_start) - lock_length = OFFSET_MAX - flock->fl_start; - - flock->fl_end = flock->fl_start + lock_length; - - if (flock->fl_end < flock->fl_start) { - ksmbd_debug(SMB, - "the end offset(%llx) is smaller than the start offset(%llx)\n", - flock->fl_end, flock->fl_start); - rsp->hdr.Status = STATUS_INVALID_LOCK_RANGE; - locks_free_lock(flock); - goto out; - } + flock->fl_start = lock_start; + flock->fl_end = lock_length ? + flock->fl_start + lock_length - 1 : flock->fl_start; /* Check conflict locks in one request */ list_for_each_entry(cmp_lock, &lock_list, llist) { @@ -7758,7 +7743,8 @@ int smb2_lock(struct ksmbd_work *work) } } - smb_lock = smb2_lock_init(flock, cmd, flags, &lock_list); + smb_lock = smb2_lock_init(flock, cmd, flags, !lock_length, + &lock_list); if (!smb_lock) { err = -EINVAL; locks_free_lock(flock); @@ -7832,7 +7818,7 @@ int smb2_lock(struct ksmbd_work *work) /* check zero byte lock range */ if (cmp_lock->zero_len && !smb_lock->zero_len && cmp_lock->start > smb_lock->start && - cmp_lock->start < smb_lock->end) { + cmp_lock->start <= smb_lock->end) { spin_unlock(&conn->llist_lock); up_read(&conn_list_lock); pr_err("previous lock conflict with zero byte lock range\n"); @@ -7841,17 +7827,15 @@ int smb2_lock(struct ksmbd_work *work) if (smb_lock->zero_len && !cmp_lock->zero_len && smb_lock->start > cmp_lock->start && - smb_lock->start < cmp_lock->end) { + smb_lock->start <= cmp_lock->end) { spin_unlock(&conn->llist_lock); up_read(&conn_list_lock); pr_err("current lock conflict with zero byte lock range\n"); goto out; } - if (((cmp_lock->start <= smb_lock->start && - cmp_lock->end > smb_lock->start) || - (cmp_lock->start < smb_lock->end && - cmp_lock->end >= smb_lock->end)) && + if (cmp_lock->start <= smb_lock->end && + smb_lock->start <= cmp_lock->end && !cmp_lock->zero_len && !smb_lock->zero_len) { spin_unlock(&conn->llist_lock); up_read(&conn_list_lock); -- 2.53.0