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 7A68840BCD4; Fri, 4 Sep 2026 05:54:51 +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=1788501292; cv=none; b=EBmJuBBmiNQjfVl6XnYX9iX+bj113la5/qjnNin3czxC/sXIjiMgPIyHvhbzgp5WT4Bw5wh71qmQXm0wv0tvlQ68j21NOMzOKskCPCFgwL9huI+YhJaKAx59vxiTAL7swQopMtRYytkTtiYPJ077QROqExPrAPu9uVuXe+FCdZI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788501292; c=relaxed/simple; bh=dPDzRhygKH4wzLvck2yJuJn3YsUy2nAqSIK5R+BegS8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AL2qmd6jpD9mX2nlrzSYZotdXssrCWD9T40Q4fwpa6h26VcIdap8uYWTZYha5OBU/q+WTeJZCwwdDAXTAMsqcLtZWd3LqAfzmwwJOLyIzbAYnCdaOJ3nSZ4lxbKt3drL8dwXj8jVgxfuiiPQwwDn7EzD4ogJsb/Fa9WGXNubvu0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AVX/cx3q; 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="AVX/cx3q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C61061F00A3D; Fri, 4 Sep 2026 05:54:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788501291; bh=Dmo7G/fKiXnrnZd4QaBOxgkhknqZXZnwc749is7g7Tk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AVX/cx3qrViQs2oAKvR8uotGsLEN9Mo/u9l0E3P/643LqmEiv9ZEf+4eE3q+DHUXP mjjGDYhkEVdwSbeRI8bup704lgqwLFRo6kuYzPq2z7Cm2lwcsApGnR/9gMaLp5AudL ce/Yw6amYT/Uv2rq/A3VLu4xvs6Ukbz+8sWMPqZI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yehyeong Lee , Keith Busch Subject: [PATCH 6.18 359/552] nvme-tcp: fix host memory disclosure on R2T for a read command Date: Fri, 4 Sep 2026 06:58:36 +0200 Message-ID: <20260904045758.376966106@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045747.813364717@linuxfoundation.org> References: <20260904045747.813364717@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yehyeong Lee commit 6efbc52237facda35d2d874fe1765bb4839275d8 upstream. nvme_tcp_handle_r2t() does not check the direction of the request the R2T refers to. A malicious controller can send an R2T for a READ and the host will answer it: nvme_tcp_setup_h2c_data_pdu() builds the H2CData header and nvme_tcp_try_send_data() sends the request's data buffer. That buffer is the READ destination, so its contents go to the controller. The command then completes normally and nothing is logged. Against a test controller that answers every READ with an R2T, a 4096 byte buffered read returned all 4096 bytes, split over two R2Ts. The pages contained stale kernel data, including an array of struct page pointers. Reject an R2T for a request that is not a write. 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 | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -756,6 +756,13 @@ static int nvme_tcp_handle_r2t(struct nv } req = blk_mq_rq_to_pdu(rq); + if (unlikely(rq_data_dir(rq) != WRITE)) { + dev_err(queue->ctrl->ctrl.device, + "req %d unexpected r2t for a non-write command\n", + rq->tag); + return -EPROTO; + } + if (unlikely(!r2t_length)) { dev_err(queue->ctrl->ctrl.device, "req %d r2t len is %u, probably a bug...\n",