Commit message: USB: uas: fix bug in handling of alternate settings

The uas driver has a subtle bug in the way it handles alternate
settings.  The uas_find_uas_alt_setting() routine returns an
altsetting value (the bAlternateSetting number in the descriptor), but
uas_use_uas_driver() then treats that value as an index to the
intf->altsetting array, which it isn't.

Normally this doesn't cause any problems because the various
alternate settings have bAlternateSetting values 0, 1, 2, ..., so the
value is equal to the index in the array.  But this is not guaranteed,
and Andrey Konovalov used the syzkaller fuzzer with KASAN to get a
slab-out-of-bounds error by violating this assumption.

This patch fixes the bug by making uas_find_uas_alt_setting() return a
pointer to the altsetting entry rather than either the value or the
index.  Pointers are less subject to misinterpretation.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
CC: Oliver Neukum <oneukum@suse.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CVE: CVE-2017-16530
CWE: CWE-125
Vulnerability description: The uas driver in the Linux kernel before 4.13.6 allows local users to cause a denial of service (out-of-bounds read and system crash) or possibly have unspecified other impact via a crafted USB device, related to drivers/usb/storage/uas-detect.h and drivers/usb/storage/uas.c.

Project: linux
File: uas.c

static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
					struct scsi_cmnd *cmnd)
{
	struct usb_device *udev = devinfo->udev;
	struct scsi_device *sdev = cmnd->device;
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	struct urb *urb = usb_alloc_urb(0, gfp);
	struct command_iu *iu;
	int len;

	if (!urb)
		goto out;

	len = cmnd->cmd_len - 16;
	if (len < 0)
		len = 0;
	len = ALIGN(len, 4);
	iu = kzalloc(sizeof(*iu) + len, gfp);
	if (!iu)
		goto free;

	iu->iu_id = IU_ID_COMMAND;
	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
	iu->prio_attr = UAS_SIMPLE_TAG;
	iu->len = len;
	int_to_scsilun(sdev->lun, &iu->lun);
	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);

	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
							uas_cmd_cmplt, NULL);
	urb->transfer_flags |= URB_FREE_BUFFER;
 out:
	return urb;
 free:
	usb_free_urb(urb);
	return NULL;
}

Project: linux
File: uas.c

static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
				      struct scsi_cmnd *cmnd,
				      enum dma_data_direction dir)
{
	struct usb_device *udev = devinfo->udev;
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	struct urb *urb = usb_alloc_urb(0, gfp);
	struct scsi_data_buffer *sdb = (dir == DMA_FROM_DEVICE)
		? scsi_in(cmnd) : scsi_out(cmnd);
	unsigned int pipe = (dir == DMA_FROM_DEVICE)
		? devinfo->data_in_pipe : devinfo->data_out_pipe;

	if (!urb)
		goto out;
	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
			  uas_data_cmplt, cmnd);
	if (devinfo->use_streams)
		urb->stream_id = cmdinfo->uas_tag;
	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
	urb->sg = sdb->table.sgl;
 out:
	return urb;
}

Project: linux
File: uas.c

static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
				       struct scsi_cmnd *cmnd)
{
	struct usb_device *udev = devinfo->udev;
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	struct urb *urb = usb_alloc_urb(0, gfp);
	struct sense_iu *iu;

	if (!urb)
		goto out;

	iu = kzalloc(sizeof(*iu), gfp);
	if (!iu)
		goto free;

	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
			  uas_stat_cmplt, cmnd->device->host);
	if (devinfo->use_streams)
		urb->stream_id = cmdinfo->uas_tag;
	urb->transfer_flags |= URB_FREE_BUFFER;
 out:
	return urb;
 free:
	usb_free_urb(urb);
	return NULL;
}

Project: linux
File: uas.c

static void uas_cmd_cmplt(struct urb *urb)
{
	if (urb->status)
		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);

	usb_free_urb(urb);
}

Project: linux
File: uas.c

static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
{
	unsigned long flags;
	int i, r = 1;

	spin_lock_irqsave(&devinfo->lock, flags);

	for (i = 0; i < devinfo->qdepth; i++) {
		if (devinfo->cmnd[i]) {
			r = 0; /* Not empty */
			break;
		}
	}

	spin_unlock_irqrestore(&devinfo->lock, flags);

	return r;
}

Project: linux
File: uas.c

 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
{
	struct usb_host_endpoint *eps[4] = { };
	struct usb_device *udev = devinfo->udev;
	int r;

	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
	if (r)
		return r;

	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
					    usb_endpoint_num(&eps[0]->desc));
	devinfo->status_pipe = usb_rcvbulkpipe(udev,
					    usb_endpoint_num(&eps[1]->desc));
	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
					    usb_endpoint_num(&eps[2]->desc));
	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
					    usb_endpoint_num(&eps[3]->desc));

	if (udev->speed < USB_SPEED_SUPER) {
		devinfo->qdepth = 32;
		devinfo->use_streams = 0;
	} else {
		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
						    3, MAX_CMNDS, GFP_NOIO);
		if (devinfo->qdepth < 0)
			return devinfo->qdepth;
		devinfo->use_streams = 1;
	}

	return 0;
}

Project: linux
File: uas.c

static void uas_data_cmplt(struct urb *urb)
{
	struct scsi_cmnd *cmnd = urb->context;
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
	struct scsi_data_buffer *sdb = NULL;
	unsigned long flags;
	int status = urb->status;

	spin_lock_irqsave(&devinfo->lock, flags);

	if (cmdinfo->data_in_urb == urb) {
		sdb = scsi_in(cmnd);
		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
		cmdinfo->data_in_urb = NULL;
	} else if (cmdinfo->data_out_urb == urb) {
		sdb = scsi_out(cmnd);
		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
		cmdinfo->data_out_urb = NULL;
	}
	if (sdb == NULL) {
		WARN_ON_ONCE(1);
		goto out;
	}

	if (devinfo->resetting)
		goto out;

	/* Data urbs should not complete before the cmd urb is submitted */
	if (cmdinfo->state & SUBMIT_CMD_URB) {
		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
		goto out;
	}

	if (status) {
		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
			uas_log_cmd_state(cmnd, "data cmplt err", status);
		/* error: no data transfered */
		sdb->resid = sdb->length;
	} else {
		sdb->resid = sdb->length - urb->actual_length;
	}
	uas_try_complete(cmnd, __func__);
out:
	usb_free_urb(urb);
	spin_unlock_irqrestore(&devinfo->lock, flags);
}

Project: linux
File: uas.c

static void uas_disconnect(struct usb_interface *intf)
{
	struct Scsi_Host *shost = usb_get_intfdata(intf);
	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
	unsigned long flags;

	spin_lock_irqsave(&devinfo->lock, flags);
	devinfo->resetting = 1;
	spin_unlock_irqrestore(&devinfo->lock, flags);

	cancel_work_sync(&devinfo->work);
	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
	usb_kill_anchored_urbs(&devinfo->sense_urbs);
	usb_kill_anchored_urbs(&devinfo->data_urbs);
	uas_zap_pending(devinfo, DID_NO_CONNECT);

	scsi_remove_host(shost);
	uas_free_streams(devinfo);
	scsi_host_put(shost);
}

Project: linux
File: uas.c

static void uas_do_work(struct work_struct *work)
{
	struct uas_dev_info *devinfo =
		container_of(work, struct uas_dev_info, work);
	struct uas_cmd_info *cmdinfo;
	struct scsi_cmnd *cmnd;
	unsigned long flags;
	int i, err;

	spin_lock_irqsave(&devinfo->lock, flags);

	if (devinfo->resetting)
		goto out;

	for (i = 0; i < devinfo->qdepth; i++) {
		if (!devinfo->cmnd[i])
			continue;

		cmnd = devinfo->cmnd[i];
		cmdinfo = (void *)&cmnd->SCp;

		if (!(cmdinfo->state & IS_IN_WORK_LIST))
			continue;

		err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
		if (!err)
			cmdinfo->state &= ~IS_IN_WORK_LIST;
		else
			schedule_work(&devinfo->work);
	}
out:
	spin_unlock_irqrestore(&devinfo->lock, flags);
}

Project: linux
File: uas.c

static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
{
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
	struct urb *data_in_urb = NULL;
	struct urb *data_out_urb = NULL;
	unsigned long flags;

	spin_lock_irqsave(&devinfo->lock, flags);

	uas_log_cmd_state(cmnd, __func__, 0);

	/* Ensure that try_complete does not call scsi_done */
	cmdinfo->state |= COMMAND_ABORTED;

	/* Drop all refs to this cmnd, kill data urbs to break their ref */
	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);

	uas_free_unsubmitted_urbs(cmnd);

	spin_unlock_irqrestore(&devinfo->lock, flags);

	if (data_in_urb) {
		usb_kill_urb(data_in_urb);
		usb_put_urb(data_in_urb);
	}
	if (data_out_urb) {
		usb_kill_urb(data_out_urb);
		usb_put_urb(data_out_urb);
	}

	return FAILED;
}

Project: linux
File: uas.c

static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
{
	struct scsi_device *sdev = cmnd->device;
	struct uas_dev_info *devinfo = sdev->hostdata;
	struct usb_device *udev = devinfo->udev;
	unsigned long flags;
	int err;

	err = usb_lock_device_for_reset(udev, devinfo->intf);
	if (err) {
		shost_printk(KERN_ERR, sdev->host,
			     "%s FAILED to get lock err %d\n", __func__, err);
		return FAILED;
	}

	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);

	spin_lock_irqsave(&devinfo->lock, flags);
	devinfo->resetting = 1;
	spin_unlock_irqrestore(&devinfo->lock, flags);

	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
	usb_kill_anchored_urbs(&devinfo->sense_urbs);
	usb_kill_anchored_urbs(&devinfo->data_urbs);
	uas_zap_pending(devinfo, DID_RESET);

	err = usb_reset_device(udev);

	spin_lock_irqsave(&devinfo->lock, flags);
	devinfo->resetting = 0;
	spin_unlock_irqrestore(&devinfo->lock, flags);

	usb_unlock_device(udev);

	if (err) {
		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
			     __func__, err);
		return FAILED;
	}

	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
	return SUCCESS;
}

Project: linux
File: uas.c

static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
{
	u8 response_code = riu->response_code;

	switch (response_code) {
	case RC_INCORRECT_LUN:
		cmnd->result = DID_BAD_TARGET << 16;
		break;
	case RC_TMF_SUCCEEDED:
		cmnd->result = DID_OK << 16;
		break;
	case RC_TMF_NOT_SUPPORTED:
		cmnd->result = DID_TARGET_FAILURE << 16;
		break;
	default:
		uas_log_cmd_state(cmnd, "response iu", response_code);
		cmnd->result = DID_ERROR << 16;
		break;
	}

	return response_code == RC_TMF_SUCCEEDED;
}

Project: linux
File: uas.c

static void uas_free_streams(struct uas_dev_info *devinfo)
{
	struct usb_device *udev = devinfo->udev;
	struct usb_host_endpoint *eps[3];

	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
}

Project: linux
File: uas.c

static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
{
	struct uas_cmd_info *cmdinfo;

	if (!cmnd)
		return;

	cmdinfo = (void *)&cmnd->SCp;

	if (cmdinfo->state & SUBMIT_CMD_URB)
		usb_free_urb(cmdinfo->cmd_urb);

	/* data urbs may have never gotten their submit flag set */
	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
		usb_free_urb(cmdinfo->data_in_urb);
	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
		usb_free_urb(cmdinfo->data_out_urb);
}

Project: linux
File: uas.c

static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
			      int status)
{
	struct uas_cmd_info *ci = (void *)&cmnd->SCp;
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;

	scmd_printk(KERN_INFO, cmnd,
		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
		    prefix, status, cmdinfo->uas_tag,
		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
	scsi_print_command(cmnd);
}

Project: linux
File: uas.c

static int uas_pre_reset(struct usb_interface *intf)
{
	struct Scsi_Host *shost = usb_get_intfdata(intf);
	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
	unsigned long flags;

	if (devinfo->shutdown)
		return 0;

	/* Block new requests */
	spin_lock_irqsave(shost->host_lock, flags);
	scsi_block_requests(shost);
	spin_unlock_irqrestore(shost->host_lock, flags);

	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
		scsi_unblock_requests(shost);
		return 1;
	}

	uas_free_streams(devinfo);

	return 0;
}

Project: linux
File: uas.c

static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
					void (*done)(struct scsi_cmnd *))
{
	struct scsi_device *sdev = cmnd->device;
	struct uas_dev_info *devinfo = sdev->hostdata;
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	unsigned long flags;
	int idx, err;

	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));

	/* Re-check scsi_block_requests now that we've the host-lock */
	if (cmnd->device->host->host_self_blocked)
		return SCSI_MLQUEUE_DEVICE_BUSY;

	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
		       sizeof(usb_stor_sense_invalidCDB));
		cmnd->result = SAM_STAT_CHECK_CONDITION;
		cmnd->scsi_done(cmnd);
		return 0;
	}

	spin_lock_irqsave(&devinfo->lock, flags);

	if (devinfo->resetting) {
		cmnd->result = DID_ERROR << 16;
		cmnd->scsi_done(cmnd);
		spin_unlock_irqrestore(&devinfo->lock, flags);
		return 0;
	}

	/* Find a free uas-tag */
	for (idx = 0; idx < devinfo->qdepth; idx++) {
		if (!devinfo->cmnd[idx])
			break;
	}
	if (idx == devinfo->qdepth) {
		spin_unlock_irqrestore(&devinfo->lock, flags);
		return SCSI_MLQUEUE_DEVICE_BUSY;
	}

	cmnd->scsi_done = done;

	memset(cmdinfo, 0, sizeof(*cmdinfo));
	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;

	switch (cmnd->sc_data_direction) {
	case DMA_FROM_DEVICE:
		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
		break;
	case DMA_BIDIRECTIONAL:
		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
	case DMA_TO_DEVICE:
		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
	case DMA_NONE:
		break;
	}

	if (!devinfo->use_streams)
		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);

	err = uas_submit_urbs(cmnd, devinfo);
	if (err) {
		/* If we did nothing, give up now */
		if (cmdinfo->state & SUBMIT_STATUS_URB) {
			spin_unlock_irqrestore(&devinfo->lock, flags);
			return SCSI_MLQUEUE_DEVICE_BUSY;
		}
		uas_add_work(cmdinfo);
	}

	devinfo->cmnd[idx] = cmnd;
	spin_unlock_irqrestore(&devinfo->lock, flags);
	return 0;
}

Project: linux
File: uas.c

static int uas_reset_resume(struct usb_interface *intf)
{
	struct Scsi_Host *shost = usb_get_intfdata(intf);
	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
	unsigned long flags;
	int err;

	err = uas_configure_endpoints(devinfo);
	if (err) {
		shost_printk(KERN_ERR, shost,
			     "%s: alloc streams error %d after reset",
			     __func__, err);
		return -EIO;
	}

	spin_lock_irqsave(shost->host_lock, flags);
	scsi_report_bus_reset(shost, 0);
	spin_unlock_irqrestore(shost->host_lock, flags);

	return 0;
}

Project: linux
File: uas.c

static int uas_resume(struct usb_interface *intf)
{
	return 0;
}

Project: linux
File: uas.c

static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
{
	struct sense_iu *sense_iu = urb->transfer_buffer;
	struct scsi_device *sdev = cmnd->device;

	if (urb->actual_length > 16) {
		unsigned len = be16_to_cpup(&sense_iu->len);
		if (len + 16 != urb->actual_length) {
			int newlen = min(len + 16, urb->actual_length) - 16;
			if (newlen < 0)
				newlen = 0;
			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
				"disagrees with IU sense data length %d, "
				"using %d bytes of sense data\n", __func__,
					urb->actual_length, len, newlen);
			len = newlen;
		}
		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
	}

	cmnd->result = sense_iu->status;
}

Project: linux
File: uas.c

static void uas_shutdown(struct device *dev)
{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_device *udev = interface_to_usbdev(intf);
	struct Scsi_Host *shost = usb_get_intfdata(intf);
	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;

	if (system_state != SYSTEM_RESTART)
		return;

	devinfo->shutdown = 1;
	uas_free_streams(devinfo);
	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
	usb_reset_device(udev);
}

Project: linux
File: uas.c

static int uas_slave_alloc(struct scsi_device *sdev)
{
	struct uas_dev_info *devinfo =
		(struct uas_dev_info *)sdev->host->hostdata;

	sdev->hostdata = devinfo;

	/*
	 * USB has unusual DMA-alignment requirements: Although the
	 * starting address of each scatter-gather element doesn't matter,
	 * the length of each element except the last must be divisible
	 * by the Bulk maxpacket value.  There's currently no way to
	 * express this by block-layer constraints, so we'll cop out
	 * and simply require addresses to be aligned at 512-byte
	 * boundaries.  This is okay since most block I/O involves
	 * hardware sectors that are multiples of 512 bytes in length,
	 * and since host controllers up through USB 2.0 have maxpacket
	 * values no larger than 512.
	 *
	 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
	 * values can be as large as 2048.  To make that work properly
	 * will require changes to the block layer.
	 */
	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));

	if (devinfo->flags & US_FL_MAX_SECTORS_64)
		blk_queue_max_hw_sectors(sdev->request_queue, 64);
	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
		blk_queue_max_hw_sectors(sdev->request_queue, 240);

	return 0;
}

Project: linux
File: uas.c

static int uas_slave_configure(struct scsi_device *sdev)
{
	struct uas_dev_info *devinfo = sdev->hostdata;

	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
		sdev->no_report_opcodes = 1;

	/* A few buggy USB-ATA bridges don't understand FUA */
	if (devinfo->flags & US_FL_BROKEN_FUA)
		sdev->broken_fua = 1;

	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
	return 0;
}

Project: linux
File: uas.c

static void uas_stat_cmplt(struct urb *urb)
{
	struct iu *iu = urb->transfer_buffer;
	struct Scsi_Host *shost = urb->context;
	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
	struct urb *data_in_urb = NULL;
	struct urb *data_out_urb = NULL;
	struct scsi_cmnd *cmnd;
	struct uas_cmd_info *cmdinfo;
	unsigned long flags;
	unsigned int idx;
	int status = urb->status;
	bool success;

	spin_lock_irqsave(&devinfo->lock, flags);

	if (devinfo->resetting)
		goto out;

	if (status) {
		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
		goto out;
	}

	idx = be16_to_cpup(&iu->tag) - 1;
	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
		dev_err(&urb->dev->dev,
			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
		goto out;
	}

	cmnd = devinfo->cmnd[idx];
	cmdinfo = (void *)&cmnd->SCp;

	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
		goto out;
	}

	switch (iu->iu_id) {
	case IU_ID_STATUS:
		uas_sense(urb, cmnd);
		if (cmnd->result != 0) {
			/* cancel data transfers on error */
			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
		}
		cmdinfo->state &= ~COMMAND_INFLIGHT;
		uas_try_complete(cmnd, __func__);
		break;
	case IU_ID_READ_READY:
		if (!cmdinfo->data_in_urb ||
				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
			break;
		}
		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
		break;
	case IU_ID_WRITE_READY:
		if (!cmdinfo->data_out_urb ||
				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
			break;
		}
		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
		break;
	case IU_ID_RESPONSE:
		cmdinfo->state &= ~COMMAND_INFLIGHT;
		success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
		if (!success) {
			/* Error, cancel data transfers */
			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
		}
		uas_try_complete(cmnd, __func__);
		break;
	default:
		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
	}
out:
	usb_free_urb(urb);
	spin_unlock_irqrestore(&devinfo->lock, flags);

	/* Unlinking of data urbs must be done without holding the lock */
	if (data_in_urb) {
		usb_unlink_urb(data_in_urb);
		usb_put_urb(data_in_urb);
	}
	if (data_out_urb) {
		usb_unlink_urb(data_out_urb);
		usb_put_urb(data_out_urb);
	}
}

Project: linux
File: uas.c

static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
{
	struct uas_dev_info *devinfo = cmnd->device->hostdata;
	struct urb *urb;
	int err;

	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
	if (!urb)
		return NULL;
	usb_anchor_urb(urb, &devinfo->sense_urbs);
	err = usb_submit_urb(urb, gfp);
	if (err) {
		usb_unanchor_urb(urb);
		uas_log_cmd_state(cmnd, "sense submit err", err);
		usb_free_urb(urb);
		return NULL;
	}
	return urb;
}

Project: linux
File: uas.c

static int uas_suspend(struct usb_interface *intf, pm_message_t message)
{
	struct Scsi_Host *shost = usb_get_intfdata(intf);
	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;

	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
		return -ETIME;
	}

	return 0;
}

Project: linux
File: uas.c

static int uas_target_alloc(struct scsi_target *starget)
{
	struct uas_dev_info *devinfo = (struct uas_dev_info *)
			dev_to_shost(starget->dev.parent)->hostdata;

	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
		starget->no_report_luns = 1;

	return 0;
}

Project: linux
File: uas.c

static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
{
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;

	lockdep_assert_held(&devinfo->lock);
	if (cmdinfo->state & (COMMAND_INFLIGHT |
			      DATA_IN_URB_INFLIGHT |
			      DATA_OUT_URB_INFLIGHT |
			      COMMAND_ABORTED))
		return -EBUSY;
	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
	uas_free_unsubmitted_urbs(cmnd);
	cmnd->scsi_done(cmnd);
	return 0;
}

Project: linux
File: uas.c

static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
{
	unsigned long start_time;
	int r;

	start_time = jiffies;
	do {
		flush_work(&devinfo->work);

		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
		if (r == 0)
			return -ETIME;

		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
		if (r == 0)
			return -ETIME;

		if (time_after(jiffies, start_time + 5 * HZ))
			return -ETIME;
	} while (!uas_cmnd_list_empty(devinfo));

	return 0;
}

Project: linux
File: uas.c

static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
			  unsigned direction)
{
	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
	int err;

	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
	if (err) {
		uas_add_work(cmdinfo);
	}
}

Project: linux
File: uas.c

static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
{
	struct uas_cmd_info *cmdinfo;
	struct scsi_cmnd *cmnd;
	unsigned long flags;
	int i, err;

	spin_lock_irqsave(&devinfo->lock, flags);
	for (i = 0; i < devinfo->qdepth; i++) {
		if (!devinfo->cmnd[i])
			continue;

		cmnd = devinfo->cmnd[i];
		cmdinfo = (void *)&cmnd->SCp;
		uas_log_cmd_state(cmnd, __func__, 0);
		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
		cmdinfo->state &= ~COMMAND_INFLIGHT;
		cmnd->result = result << 16;
		err = uas_try_complete(cmnd, __func__);
		WARN_ON(err != 0);
	}
	spin_unlock_irqrestore(&devinfo->lock, flags);
}