From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 6AA4B4C0402 for ; Thu, 3 Sep 2026 15:03:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788447783; cv=none; b=mMj5Rm48KcWIjgcbYfXHWMXtJBDipoWu86Uudq2JqyF8Vmfe2FIk1oZB3i8/3NeLPDOnYrKYrBGsrvAYZ2FdPfeOoT0VJShGCIQJ14mGeABg84bvO3/jQZnnhvLMleOpphUDYxqSyhHB4kBgUIUVQokPEpG4mNuu+E2qOG68AMc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788447783; c=relaxed/simple; bh=XfmZTabAbQE9LuTd8mV+LErGdNi97bWxyyotpJfvdIE=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=s+wCCJfVdhyIZPupokpQjnjKGbsan60VFOX2be/jxaCF5Fk26E+IciD3TodcUn1Rw1mFeeuvQaWde5ZD0DaWl4mz8h1ytdH0N4e388yw+xOph9gSM7qPHJNZS9DqNhrcH8Kt0qmB+/dXgsSZvntkZocVTKjPE5nQu7AwJlgob88= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=fTRBw4Kd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="fTRBw4Kd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C56481F000E9; Thu, 3 Sep 2026 15:03:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788447782; bh=Owtko8V5Al8ZIBagkVRJP/g3pP0NK50jpmet/W9DL+o=; h=Subject:To:Cc:From:Date; b=fTRBw4KdeE8kooT0uwl6PcV5Lne1+A38nsRlwODChO/NqnRlIDuXuyQhITf2uZa9r l5KJ/BySkW5/ziarF1jFFR8Df0qLwd0MQSKS8LrlQuY4isvOugp8aHZafReFUzxyId 8aJ/D6vketayk3r4/pnMb0n6gy4hnN7jGRhLuHw4= Subject: FAILED: patch "[PATCH] nvme-tcp: reject a read that transferred too few bytes" failed to apply to 5.10-stable tree To: yhlee@isslab.korea.ac.kr,kbusch@kernel.org Cc: From: Date: Thu, 03 Sep 2026 16:36:17 +0200 Message-ID: <2026090316-lying-divisive-d066@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12 # git commit -s git send-email --to '' --in-reply-to '2026090316-lying-divisive-d066@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12 Mon Sep 17 00:00:00 2001 From: Yehyeong Lee Date: Sat, 1 Aug 2026 17:18:17 +0900 Subject: [PATCH] nvme-tcp: reject a read that transferred too few bytes nvme_tcp_recv_data() completes a request once the current C2HData PDU has been consumed. Nothing compares the total bytes received against the length the command asked for: struct nvme_tcp_request has no receive-side counter, queue->data_remaining is per queue, and blk_mq_end_request() completes for blk_rq_bytes(rq) unconditionally with no residual concept anywhere above. A controller can therefore answer a 4096-byte read with 512 bytes and have it reported as a complete read; user space then gets 4096 bytes of which 3584 are whatever was already in the page. I reproduced that with a test target. Count the bytes received and refuse to complete a successful read whose count does not match, at the two NVME_TCP_F_DATA_SUCCESS paths and in nvme_tcp_process_nvme_cqe(). The success test shifts req->status right by one, because the driver keeps the wire value there and shifts it on completion, so the check must see what the completion path will see. Only REQ_OP_READ is checked, because there the length comes from the sectors the request covers; a passthrough command is built by its submitter, which picks both command and buffer, so the kernel has nothing to compare against. Fixes: 3f2304f8c6d6 ("nvme-tcp: add NVMe over TCP host driver") Cc: stable@vger.kernel.org Signed-off-by: Yehyeong Lee Signed-off-by: Keith Busch diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 1d303e54e13e..3655f7607be0 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -80,6 +80,7 @@ struct nvme_tcp_request { struct bio *curr_bio; struct iov_iter iter; + u32 data_recvd; /* send state */ size_t offset; @@ -617,6 +618,29 @@ static void nvme_tcp_error_recovery(struct nvme_ctrl *ctrl) queue_work(nvme_reset_wq, &to_tcp_ctrl(ctrl)->err_work); } +/* + * NVMe has no short read: a read that completes successfully must + * have transferred everything it asked for. + */ +static bool nvme_tcp_data_in_short(struct nvme_tcp_queue *queue, + struct request *rq) +{ + struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq); + + if (le16_to_cpu(req->status) >> 1) + return false; + if (req_op(rq) != REQ_OP_READ || !req->data_len) + return false; + if (likely(req->data_recvd == req->data_len)) + return false; + + dev_err(queue->ctrl->ctrl.device, + "queue %d tag %#x short data-in: got %u of %u\n", + nvme_tcp_queue_id(queue), rq->tag, + req->data_recvd, req->data_len); + return true; +} + static int nvme_tcp_process_nvme_cqe(struct nvme_tcp_queue *queue, struct nvme_completion *cqe) { @@ -636,6 +660,9 @@ static int nvme_tcp_process_nvme_cqe(struct nvme_tcp_queue *queue, if (req->status == cpu_to_le16(NVME_SC_SUCCESS)) req->status = cqe->status; + if (unlikely(nvme_tcp_data_in_short(queue, rq))) + return -EPROTO; + if (!nvme_try_complete_req(rq, req->status, cqe->result)) nvme_complete_rq(rq); queue->nr_cqe++; @@ -958,6 +985,7 @@ static int nvme_tcp_recv_data(struct nvme_tcp_queue *queue, struct sk_buff *skb, *len -= recv_len; *offset += recv_len; queue->data_remaining -= recv_len; + req->data_recvd += recv_len; } if (!queue->data_remaining) { @@ -966,6 +994,8 @@ static int nvme_tcp_recv_data(struct nvme_tcp_queue *queue, struct sk_buff *skb, queue->ddgst_remaining = NVME_TCP_DIGEST_LENGTH; } else { if (pdu->hdr.flags & NVME_TCP_F_DATA_SUCCESS) { + if (unlikely(nvme_tcp_data_in_short(queue, rq))) + return -EPROTO; nvme_tcp_end_request(rq, le16_to_cpu(req->status)); queue->nr_cqe++; @@ -1014,6 +1044,9 @@ static int nvme_tcp_recv_ddgst(struct nvme_tcp_queue *queue, pdu->command_id); struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq); + if (unlikely(nvme_tcp_data_in_short(queue, rq))) + return -EPROTO; + nvme_tcp_end_request(rq, le16_to_cpu(req->status)); queue->nr_cqe++; } @@ -2746,6 +2779,7 @@ static blk_status_t nvme_tcp_setup_cmd_pdu(struct nvme_ns *ns, req->status = cpu_to_le16(NVME_SC_SUCCESS); req->offset = 0; req->data_sent = 0; + req->data_recvd = 0; req->pdu_len = 0; req->pdu_sent = 0; req->h2cdata_left = 0;