From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2DFDE606A31C for ; Thu, 29 Oct 2026 23:11:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=YazT4mKn Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1xMZGe-00061K-BV; Thu, 29 Oct 2026 19:10:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xMZGF-0005oy-FK for qemu-devel@nongnu.org; Thu, 29 Oct 2026 19:10:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xMZGC-0004to-5h for qemu-devel@nongnu.org; Thu, 29 Oct 2026 19:10:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1793315413; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GAkypcA8H4GOZoMJ0zYDAuHv44NctvKtilUiB9J4joM=; b=YazT4mKnGnp4ZINKeHNJyN+DbNaBfVgDGuAXb6lSUED8JyyaB4rlj0ufFFYld8zusMbNf7 G2D/j7ocLpH5m5pcBLXdqnNBWHVWb7KOmMKeBUiGamWMFaxURegRYDa+tOmdNyQhcfx5XZ Sld9uMLpKioDjCO96Qnp4BLIY74xwAA= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-690-YNOPPfSwNiy8xpqfDSzk_A-1; Thu, 29 Oct 2026 19:10:10 -0400 X-MC-Unique: YNOPPfSwNiy8xpqfDSzk_A-1 X-Mimecast-MFC-AGG-ID: YNOPPfSwNiy8xpqfDSzk_A_1793315409 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 721CB18052DD; Thu, 29 Oct 2026 23:10:09 +0000 (UTC) Received: from merkur.fritz.box (unknown [10.44.32.61]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 40D6730002CB; Thu, 29 Oct 2026 23:10:06 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, hreitz@redhat.com, stefanha@redhat.com, mst@redhat.com, devel@lists.libvirt.org, qemu-devel@nongnu.org Subject: [PATCH v2 1/4] virtio-blk: Implement full NUL padding for GET_ID Date: Fri, 30 Oct 2026 00:09:58 +0100 Message-ID: <20261029231001.194240-2-kwolf@redhat.com> In-Reply-To: <20261029231001.194240-1-kwolf@redhat.com> References: <20261029231001.194240-1-kwolf@redhat.com> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 The spec requires not only NUL termination of the device ID string, but NUL padding: VIRTIO_BLK_T_GET_ID requests fetch the device ID string from the device into data. The device ID string is a NUL-padded ASCII string up to 20 bytes long. If the string is 20 bytes long then there is no NUL terminator. Zero out all of the remaining bytes in the request buffer. Signed-off-by: Kevin Wolf Reviewed-by: Stefan Hajnoczi --- hw/block/virtio-blk.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 536d71a91ad..3f236f22d57 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1011,14 +1011,18 @@ static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) case VIRTIO_BLK_T_GET_ID: { /* - * NB: per existing s/n string convention the string is + * The spec requires NUL-padding for the output. The string is * terminated by '\0' only when shorter than buffer. */ const char *serial = s->conf.serial ? s->conf.serial : ""; - size_t size = MIN(strlen(serial) + 1, - MIN(iov_size(in_iov, in_num), - VIRTIO_BLK_ID_BYTES)); + size_t req_size = MIN(iov_size(in_iov, in_num), VIRTIO_BLK_ID_BYTES); + size_t size = MIN(strlen(serial), req_size); + size_t padding = req_size - size; + iov_from_buf(in_iov, in_num, 0, serial, size); + if (padding) { + iov_memset(in_iov, in_num, size, 0, padding); + } virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); g_free(req); break; -- 2.56.0