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 C0D25317145; Sat, 12 Sep 2026 15:36:15 +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=1789227377; cv=none; b=U1S4n5wu67OV4P0gx7DSc3IyUfYKGp+twHHEntznzRrMCJasfAv4QQjz+VL6VPyGvB6JzSPZYxAK2AQal8nncWflrnbnD/mVqhWRzJW5tQggzfWROp650nCblPbjMDuPudCIkLiAZObi+oaFdi9H3d+e0XUeZwicqLNa+w12PZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789227377; c=relaxed/simple; bh=E3AScL8+CZooNaj7QaMFebeWa5NvSJ9gBLQNqw5GbZo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OxY/wGs0ehuzFJ2kbBlsyEZ3Wgs4kKZtsw6ed9W0lYPfa1xQo4DD06a6mJ2EBXP+A/fr5tX0aRNAuT2wJOYYtgLXJXPMjMV5NRutQ8mSb+K5eVZNVVgVB3CKlMuNGJ8WEBj54Ge3DoSZ7z+a9RVajib1m7SHttTai3Lnr1OpxuQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WbPL012Y; 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="WbPL012Y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99AE41F000FF; Sat, 12 Sep 2026 15:36:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789227375; bh=RaVWe4ormaJrW8tq4Vi8z8W0YMecUD0LCQWYdBYiLxI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WbPL012YmTRWmcAFjN0Ja7ExA4PP6zEzqGDRJgcetIeuquIlAxeBfOM5dFTSnFF2V 82BcnqjLYDmOZGhyNTP9TLlRMFgnnFffOrKTsRqfVfSNHkc+N4gfNM/rpL1Bat3nxa fC4b0VcmPtGwnKhWaTq+4RVMYItQhpeM9xsyQWf0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yehyeong Lee , Keith Busch Subject: [PATCH 6.1 0168/1191] nvme-tcp: reject a read that transferred too few bytes Date: Sat, 12 Sep 2026 08:48:16 +0200 Message-ID: <20260912065551.987830487@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065548.086904252@linuxfoundation.org> References: <20260912065548.086904252@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yehyeong Lee commit 7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/nvme/host/tcp.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -92,6 +92,7 @@ struct nvme_tcp_request { struct bio *curr_bio; struct iov_iter iter; + u32 data_recvd; /* send state */ size_t offset; @@ -529,6 +530,29 @@ static void nvme_tcp_error_recovery(stru 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) { @@ -548,6 +572,9 @@ static int nvme_tcp_process_nvme_cqe(str 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++; @@ -856,6 +883,7 @@ static int nvme_tcp_recv_data(struct nvm *len -= recv_len; *offset += recv_len; queue->data_remaining -= recv_len; + req->data_recvd += recv_len; } if (!queue->data_remaining) { @@ -864,6 +892,8 @@ static int nvme_tcp_recv_data(struct nvm 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++; @@ -912,6 +942,9 @@ static int nvme_tcp_recv_ddgst(struct nv 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++; } @@ -2438,6 +2471,7 @@ static blk_status_t nvme_tcp_setup_cmd_p 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;