Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 485 insertions, 0 deletions

diff --git a/drivers/usb/serial/ir-usb.c b/drivers/usb/serial/ir-usb.c
new file mode 100644
index 000000000..aac845397
--- /dev/null
+++ b/drivers/usb/serial/ir-usb.c
@@ -0,0 +1,485 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * USB IR Dongle driver
+ *
+ *	Copyright (C) 2001-2002	Greg Kroah-Hartman (greg@kroah.com)
+ *	Copyright (C) 2002	Gary Brubaker (xavyer@ix.netcom.com)
+ *	Copyright (C) 2010	Johan Hovold (jhovold@gmail.com)
+ *
+ * This driver allows a USB IrDA device to be used as a "dumb" serial device.
+ * This can be useful if you do not have access to a full IrDA stack on the
+ * other side of the connection.  If you do have an IrDA stack on both devices,
+ * please use the usb-irda driver, as it contains the proper error checking and
+ * other goodness of a full IrDA stack.
+ *
+ * Portions of this driver were taken from drivers/net/irda/irda-usb.c, which
+ * was written by Roman Weissgaerber <weissg@vienna.at>, Dag Brattli
+ * <dag@brattli.net>, and Jean Tourrilhes <jt@hpl.hp.com>
+ *
+ * See Documentation/usb/usb-serial.rst for more information on using this
+ * driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+#include <linux/usb/irda.h>
+
+#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>"
+#define DRIVER_DESC "USB IR Dongle driver"
+
+/* if overridden by the user, then use their value for the size of the read and
+ * write urbs */
+static int buffer_size;
+
+/* if overridden by the user, then use the specified number of XBOFs */
+static int xbof = -1;
+
+static int  ir_startup (struct usb_serial *serial);
+static int ir_write(struct tty_struct *tty, struct usb_serial_port *port,
+		const unsigned char *buf, int count);
+static unsigned int ir_write_room(struct tty_struct *tty);
+static void ir_write_bulk_callback(struct urb *urb);
+static void ir_process_read_urb(struct urb *urb);
+static void ir_set_termios(struct tty_struct *tty,
+			   struct usb_serial_port *port,
+			   const struct ktermios *old_termios);
+
+/* Not that this lot means you can only have one per system */
+static u8 ir_baud;
+static u8 ir_xbof;
+static u8 ir_add_bof;
+
+static const struct usb_device_id ir_id_table[] = {
+	{ USB_DEVICE(0x050f, 0x0180) },		/* KC Technology, KC-180 */
+	{ USB_DEVICE(0x08e9, 0x0100) },		/* XTNDAccess */
+	{ USB_DEVICE(0x09c4, 0x0011) },		/* ACTiSys ACT-IR2000U */
+	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) },
+	{ }					/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(usb, ir_id_table);
+
+static struct usb_serial_driver ir_device = {
+	.driver	= {
+		.name	= "ir-usb",
+	},
+	.description		= "IR Dongle",
+	.id_table		= ir_id_table,
+	.num_ports		= 1,
+	.num_bulk_in		= 1,
+	.num_bulk_out		= 1,
+	.set_termios		= ir_set_termios,
+	.attach			= ir_startup,
+	.write			= ir_write,
+	.write_room		= ir_write_room,
+	.write_bulk_callback	= ir_write_bulk_callback,
+	.process_read_urb	= ir_process_read_urb,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+	&ir_device, NULL
+};
+
+static inline void irda_usb_dump_class_desc(struct usb_serial *serial,
+					    struct usb_irda_cs_descriptor *desc)
+{
+	struct device *dev = &serial->dev->dev;
+
+	dev_dbg(dev, "bLength=%x\n", desc->bLength);
+	dev_dbg(dev, "bDescriptorType=%x\n", desc->bDescriptorType);
+	dev_dbg(dev, "bcdSpecRevision=%x\n", __le16_to_cpu(desc->bcdSpecRevision));
+	dev_dbg(dev, "bmDataSize=%x\n", desc->bmDataSize);
+	dev_dbg(dev, "bmWindowSize=%x\n", desc->bmWindowSize);
+	dev_dbg(dev, "bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
+	dev_dbg(dev, "wBaudRate=%x\n", __le16_to_cpu(desc->wBaudRate));
+	dev_dbg(dev, "bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
+	dev_dbg(dev, "bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
+	dev_dbg(dev, "bMaxUnicastList=%x\n", desc->bMaxUnicastList);
+}
+
+/*------------------------------------------------------------------*/
+/*
+ * Function irda_usb_find_class_desc(dev, ifnum)
+ *
+ *    Returns instance of IrDA class descriptor, or NULL if not found
+ *
+ * The class descriptor is some extra info that IrDA USB devices will
+ * offer to us, describing their IrDA characteristics. We will use that in
+ * irda_usb_init_qos()
+ *
+ * Based on the same function in drivers/net/irda/irda-usb.c
+ */
+static struct usb_irda_cs_descriptor *
+irda_usb_find_class_desc(struct usb_serial *serial, unsigned int ifnum)
+{
+	struct usb_device *dev = serial->dev;
+	struct usb_irda_cs_descriptor *desc;
+	int ret;
+
+	desc = kzalloc_obj(*desc);
+	if (!desc)
+		return NULL;
+
+	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
+			USB_REQ_CS_IRDA_GET_CLASS_DESC,
+			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			0, ifnum, desc, sizeof(*desc), 1000);
+
+	dev_dbg(&serial->dev->dev, "%s -  ret=%d\n", __func__, ret);
+	if (ret < (int)sizeof(*desc)) {
+		dev_dbg(&serial->dev->dev,
+			"%s - class descriptor read %s (%d)\n", __func__,
+			(ret < 0) ? "failed" : "too short", ret);
+		goto error;
+	}
+	if (desc->bDescriptorType != USB_DT_CS_IRDA) {
+		dev_dbg(&serial->dev->dev, "%s - bad class descriptor type\n",
+			__func__);
+		goto error;
+	}
+
+	irda_usb_dump_class_desc(serial, desc);
+	return desc;
+
+error:
+	kfree(desc);
+	return NULL;
+}
+
+static u8 ir_xbof_change(u8 xbof)
+{
+	u8 result;
+
+	/* reference irda-usb.c */
+	switch (xbof) {
+	case 48:
+		result = 0x10;
+		break;
+	case 28:
+	case 24:
+		result = 0x20;
+		break;
+	default:
+	case 12:
+		result = 0x30;
+		break;
+	case  5:
+	case  6:
+		result = 0x40;
+		break;
+	case  3:
+		result = 0x50;
+		break;
+	case  2:
+		result = 0x60;
+		break;
+	case  1:
+		result = 0x70;
+		break;
+	case  0:
+		result = 0x80;
+		break;
+	}
+
+	return(result);
+}
+
+static int ir_startup(struct usb_serial *serial)
+{
+	struct usb_irda_cs_descriptor *irda_desc;
+	int rates;
+
+	irda_desc = irda_usb_find_class_desc(serial, 0);
+	if (!irda_desc) {
+		dev_err(&serial->dev->dev,
+			"IRDA class descriptor not found, device not bound\n");
+		return -ENODEV;
+	}
+
+	rates = le16_to_cpu(irda_desc->wBaudRate);
+
+	dev_dbg(&serial->dev->dev,
+		"%s - Baud rates supported:%s%s%s%s%s%s%s%s%s\n",
+		__func__,
+		(rates & USB_IRDA_BR_2400) ? " 2400" : "",
+		(rates & USB_IRDA_BR_9600) ? " 9600" : "",
+		(rates & USB_IRDA_BR_19200) ? " 19200" : "",
+		(rates & USB_IRDA_BR_38400) ? " 38400" : "",
+		(rates & USB_IRDA_BR_57600) ? " 57600" : "",
+		(rates & USB_IRDA_BR_115200) ? " 115200" : "",
+		(rates & USB_IRDA_BR_576000) ? " 576000" : "",
+		(rates & USB_IRDA_BR_1152000) ? " 1152000" : "",
+		(rates & USB_IRDA_BR_4000000) ? " 4000000" : "");
+
+	switch (irda_desc->bmAdditionalBOFs) {
+	case USB_IRDA_AB_48:
+		ir_add_bof = 48;
+		break;
+	case USB_IRDA_AB_24:
+		ir_add_bof = 24;
+		break;
+	case USB_IRDA_AB_12:
+		ir_add_bof = 12;
+		break;
+	case USB_IRDA_AB_6:
+		ir_add_bof = 6;
+		break;
+	case USB_IRDA_AB_3:
+		ir_add_bof = 3;
+		break;
+	case USB_IRDA_AB_2:
+		ir_add_bof = 2;
+		break;
+	case USB_IRDA_AB_1:
+		ir_add_bof = 1;
+		break;
+	case USB_IRDA_AB_0:
+		ir_add_bof = 0;
+		break;
+	default:
+		break;
+	}
+
+	kfree(irda_desc);
+
+	return 0;
+}
+
+static int ir_write(struct tty_struct *tty, struct usb_serial_port *port,
+		const unsigned char *buf, int count)
+{
+	struct urb *urb = NULL;
+	unsigned long flags;
+	int ret;
+
+	if (port->bulk_out_size == 0)
+		return -EINVAL;
+
+	if (count == 0)
+		return 0;
+
+	count = min(count, port->bulk_out_size - 1);
+
+	spin_lock_irqsave(&port->lock, flags);
+	if (__test_and_clear_bit(0, &port->write_urbs_free)) {
+		urb = port->write_urbs[0];
+		port->tx_bytes += count;
+	}
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	if (!urb)
+		return 0;
+
+	/*
+	 * The first byte of the packet we send to the device contains an
+	 * outbound header which indicates an additional number of BOFs and
+	 * a baud rate change.
+	 *
+	 * See section 5.4.2.2 of the USB IrDA spec.
+	 */
+	*(u8 *)urb->transfer_buffer = ir_xbof | ir_baud;
+
+	memcpy(urb->transfer_buffer + 1, buf, count);
+
+	urb->transfer_buffer_length = count + 1;
+	urb->transfer_flags = URB_ZERO_PACKET;
+
+	ret = usb_submit_urb(urb, GFP_ATOMIC);
+	if (ret) {
+		dev_err(&port->dev, "failed to submit write urb: %d\n", ret);
+
+		spin_lock_irqsave(&port->lock, flags);
+		__set_bit(0, &port->write_urbs_free);
+		port->tx_bytes -= count;
+		spin_unlock_irqrestore(&port->lock, flags);
+
+		return ret;
+	}
+
+	return count;
+}
+
+static void ir_write_bulk_callback(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	int status = urb->status;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	__set_bit(0, &port->write_urbs_free);
+	port->tx_bytes -= urb->transfer_buffer_length - 1;
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	switch (status) {
+	case 0:
+		break;
+	case -ENOENT:
+	case -ECONNRESET:
+	case -ESHUTDOWN:
+		dev_dbg(&port->dev, "write urb stopped: %d\n", status);
+		return;
+	case -EPIPE:
+		dev_err(&port->dev, "write urb stopped: %d\n", status);
+		return;
+	default:
+		dev_err(&port->dev, "nonzero write-urb status: %d\n", status);
+		break;
+	}
+
+	usb_serial_port_softint(port);
+}
+
+static unsigned int ir_write_room(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	unsigned int count = 0;
+
+	if (port->bulk_out_size == 0)
+		return 0;
+
+	if (test_bit(0, &port->write_urbs_free))
+		count = port->bulk_out_size - 1;
+
+	return count;
+}
+
+static void ir_process_read_urb(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	unsigned char *data = urb->transfer_buffer;
+
+	if (!urb->actual_length)
+		return;
+	/*
+	 * The first byte of the packet we get from the device
+	 * contains a busy indicator and baud rate change.
+	 * See section 5.4.1.2 of the USB IrDA spec.
+	 */
+	if (*data & 0x0f)
+		ir_baud = *data & 0x0f;
+
+	if (urb->actual_length == 1)
+		return;
+
+	tty_insert_flip_string(&port->port, data + 1, urb->actual_length - 1);
+	tty_flip_buffer_push(&port->port);
+}
+
+static void ir_set_termios(struct tty_struct *tty,
+			   struct usb_serial_port *port,
+			   const struct ktermios *old_termios)
+{
+	struct usb_device *udev = port->serial->dev;
+	unsigned char *transfer_buffer;
+	int actual_length;
+	speed_t baud;
+	int ir_baud;
+	int ret;
+
+	baud = tty_get_baud_rate(tty);
+
+	/*
+	 * FIXME, we should compare the baud request against the
+	 * capability stated in the IR header that we got in the
+	 * startup function.
+	 */
+
+	switch (baud) {
+	case 2400:
+		ir_baud = USB_IRDA_LS_2400;
+		break;
+	case 9600:
+		ir_baud = USB_IRDA_LS_9600;
+		break;
+	case 19200:
+		ir_baud = USB_IRDA_LS_19200;
+		break;
+	case 38400:
+		ir_baud = USB_IRDA_LS_38400;
+		break;
+	case 57600:
+		ir_baud = USB_IRDA_LS_57600;
+		break;
+	case 115200:
+		ir_baud = USB_IRDA_LS_115200;
+		break;
+	case 576000:
+		ir_baud = USB_IRDA_LS_576000;
+		break;
+	case 1152000:
+		ir_baud = USB_IRDA_LS_1152000;
+		break;
+	case 4000000:
+		ir_baud = USB_IRDA_LS_4000000;
+		break;
+	default:
+		ir_baud = USB_IRDA_LS_9600;
+		baud = 9600;
+	}
+
+	if (xbof == -1)
+		ir_xbof = ir_xbof_change(ir_add_bof);
+	else
+		ir_xbof = ir_xbof_change(xbof) ;
+
+	/* Only speed changes are supported */
+	tty_termios_copy_hw(&tty->termios, old_termios);
+	tty_encode_baud_rate(tty, baud, baud);
+
+	/*
+	 * send the baud change out on an "empty" data packet
+	 */
+	transfer_buffer = kmalloc(1, GFP_KERNEL);
+	if (!transfer_buffer)
+		return;
+
+	*transfer_buffer = ir_xbof | ir_baud;
+
+	ret = usb_bulk_msg(udev,
+			usb_sndbulkpipe(udev, port->bulk_out_endpointAddress),
+			transfer_buffer, 1, &actual_length, 5000);
+	if (ret || actual_length != 1) {
+		if (!ret)
+			ret = -EIO;
+		dev_err(&port->dev, "failed to change line speed: %d\n", ret);
+	}
+
+	kfree(transfer_buffer);
+}
+
+static int __init ir_init(void)
+{
+	if (buffer_size) {
+		ir_device.bulk_in_size = buffer_size;
+		ir_device.bulk_out_size = buffer_size;
+	}
+
+	return usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, ir_id_table);
+}
+
+static void __exit ir_exit(void)
+{
+	usb_serial_deregister_drivers(serial_drivers);
+}
+
+
+module_init(ir_init);
+module_exit(ir_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+module_param(xbof, int, 0);
+MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
+module_param(buffer_size, int, 0);
+MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
+