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, 420 insertions, 0 deletions

diff --git a/drivers/usb/serial/cyberjack.c b/drivers/usb/serial/cyberjack.c
new file mode 100644
index 000000000..57e20eb02
--- /dev/null
+++ b/drivers/usb/serial/cyberjack.c
@@ -0,0 +1,420 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver
+ *
+ *  Copyright (C) 2001  REINER SCT
+ *  Author: Matthias Bruestle
+ *
+ *  Contact: support@reiner-sct.com (see MAINTAINERS)
+ *
+ *  This program is largely derived from work by the linux-usb group
+ *  and associated source files.  Please see the usb/serial files for
+ *  individual credits and copyrights.
+ *
+ *  Thanks to Greg Kroah-Hartman (greg@kroah.com) for his help and
+ *  patience.
+ *
+ *  In case of problems, please write to the contact e-mail address
+ *  mentioned above.
+ *
+ *  Please note that later models of the cyberjack reader family are
+ *  supported by a libusb-based userspace device driver.
+ *
+ *  Homepage: http://www.reiner-sct.de/support/treiber_cyberjack.php#linux
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/errno.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>
+
+#define CYBERJACK_LOCAL_BUF_SIZE 32
+
+#define DRIVER_AUTHOR "Matthias Bruestle"
+#define DRIVER_DESC "REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver"
+
+
+#define CYBERJACK_VENDOR_ID	0x0C4B
+#define CYBERJACK_PRODUCT_ID	0x0100
+
+/* Function prototypes */
+static int cyberjack_port_probe(struct usb_serial_port *port);
+static void cyberjack_port_remove(struct usb_serial_port *port);
+static int  cyberjack_open(struct tty_struct *tty,
+	struct usb_serial_port *port);
+static void cyberjack_close(struct usb_serial_port *port);
+static int cyberjack_write(struct tty_struct *tty,
+	struct usb_serial_port *port, const unsigned char *buf, int count);
+static unsigned int cyberjack_write_room(struct tty_struct *tty);
+static void cyberjack_read_int_callback(struct urb *urb);
+static void cyberjack_read_bulk_callback(struct urb *urb);
+static void cyberjack_write_bulk_callback(struct urb *urb);
+
+static const struct usb_device_id id_table[] = {
+	{ USB_DEVICE(CYBERJACK_VENDOR_ID, CYBERJACK_PRODUCT_ID) },
+	{ }			/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(usb, id_table);
+
+static struct usb_serial_driver cyberjack_device = {
+	.driver = {
+		.name =		"cyberjack",
+	},
+	.description =		"Reiner SCT Cyberjack USB card reader",
+	.id_table =		id_table,
+	.num_ports =		1,
+	.num_bulk_out =		1,
+	.port_probe =		cyberjack_port_probe,
+	.port_remove =		cyberjack_port_remove,
+	.open =			cyberjack_open,
+	.close =		cyberjack_close,
+	.write =		cyberjack_write,
+	.write_room =		cyberjack_write_room,
+	.read_int_callback =	cyberjack_read_int_callback,
+	.read_bulk_callback =	cyberjack_read_bulk_callback,
+	.write_bulk_callback =	cyberjack_write_bulk_callback,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+	&cyberjack_device, NULL
+};
+
+struct cyberjack_private {
+	spinlock_t	lock;		/* Lock for SMP */
+	short		rdtodo;		/* Bytes still to read */
+	unsigned char	wrbuf[5*64];	/* Buffer for collecting data to write */
+	short		wrfilled;	/* Overall data size we already got */
+	short		wrsent;		/* Data already sent */
+};
+
+static int cyberjack_port_probe(struct usb_serial_port *port)
+{
+	struct cyberjack_private *priv;
+	int result;
+
+	priv = kmalloc_obj(struct cyberjack_private);
+	if (!priv)
+		return -ENOMEM;
+
+	spin_lock_init(&priv->lock);
+	priv->rdtodo = 0;
+	priv->wrfilled = 0;
+	priv->wrsent = 0;
+
+	usb_set_serial_port_data(port, priv);
+
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+	if (result)
+		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
+
+	return 0;
+}
+
+static void cyberjack_port_remove(struct usb_serial_port *port)
+{
+	struct cyberjack_private *priv;
+
+	usb_kill_urb(port->interrupt_in_urb);
+
+	priv = usb_get_serial_port_data(port);
+	kfree(priv);
+}
+
+static int  cyberjack_open(struct tty_struct *tty,
+					struct usb_serial_port *port)
+{
+	struct cyberjack_private *priv;
+	unsigned long flags;
+
+	dev_dbg(&port->dev, "%s - usb_clear_halt\n", __func__);
+	usb_clear_halt(port->serial->dev, port->write_urb->pipe);
+
+	priv = usb_get_serial_port_data(port);
+	spin_lock_irqsave(&priv->lock, flags);
+	priv->rdtodo = 0;
+	priv->wrfilled = 0;
+	priv->wrsent = 0;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return 0;
+}
+
+static void cyberjack_close(struct usb_serial_port *port)
+{
+	usb_kill_urb(port->write_urb);
+	usb_kill_urb(port->read_urb);
+}
+
+static int cyberjack_write(struct tty_struct *tty,
+	struct usb_serial_port *port, const unsigned char *buf, int count)
+{
+	struct device *dev = &port->dev;
+	struct cyberjack_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	int result;
+	int wrexpected;
+
+	if (count == 0) {
+		dev_dbg(dev, "%s - write request of 0 bytes\n", __func__);
+		return 0;
+	}
+
+	if (!test_and_clear_bit(0, &port->write_urbs_free)) {
+		dev_dbg(dev, "%s - already writing\n", __func__);
+		return 0;
+	}
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	if (count+priv->wrfilled > sizeof(priv->wrbuf)) {
+		/* To much data for buffer. Reset buffer. */
+		priv->wrfilled = 0;
+		spin_unlock_irqrestore(&priv->lock, flags);
+		set_bit(0, &port->write_urbs_free);
+		return 0;
+	}
+
+	/* Copy data */
+	memcpy(priv->wrbuf + priv->wrfilled, buf, count);
+
+	usb_serial_debug_data(dev, __func__, count, priv->wrbuf + priv->wrfilled);
+	priv->wrfilled += count;
+
+	if (priv->wrfilled >= 3) {
+		wrexpected = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
+		dev_dbg(dev, "%s - expected data: %d\n", __func__, wrexpected);
+	} else
+		wrexpected = sizeof(priv->wrbuf);
+
+	if (priv->wrfilled >= wrexpected) {
+		/* We have enough data to begin transmission */
+		int length;
+
+		dev_dbg(dev, "%s - transmitting data (frame 1)\n", __func__);
+		length = (wrexpected > port->bulk_out_size) ?
+					port->bulk_out_size : wrexpected;
+
+		memcpy(port->write_urb->transfer_buffer, priv->wrbuf, length);
+		priv->wrsent = length;
+
+		/* set up our urb */
+		port->write_urb->transfer_buffer_length = length;
+
+		/* send the data out the bulk port */
+		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
+		if (result) {
+			dev_err(&port->dev,
+				"%s - failed submitting write urb, error %d\n",
+				__func__, result);
+			/* Throw away data. No better idea what to do with it. */
+			priv->wrfilled = 0;
+			priv->wrsent = 0;
+			spin_unlock_irqrestore(&priv->lock, flags);
+			set_bit(0, &port->write_urbs_free);
+			return 0;
+		}
+
+		dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent);
+		dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled);
+
+		if (priv->wrsent >= priv->wrfilled) {
+			dev_dbg(dev, "%s - buffer cleaned\n", __func__);
+			memset(priv->wrbuf, 0, sizeof(priv->wrbuf));
+			priv->wrfilled = 0;
+			priv->wrsent = 0;
+		}
+	}
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return count;
+}
+
+static unsigned int cyberjack_write_room(struct tty_struct *tty)
+{
+	/* FIXME: .... */
+	return CYBERJACK_LOCAL_BUF_SIZE;
+}
+
+static void cyberjack_read_int_callback(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	struct cyberjack_private *priv = usb_get_serial_port_data(port);
+	struct device *dev = &port->dev;
+	unsigned char *data = urb->transfer_buffer;
+	int status = urb->status;
+	unsigned long flags;
+	int result;
+
+	/* the urb might have been killed. */
+	if (status)
+		return;
+
+	usb_serial_debug_data(dev, __func__, urb->actual_length, data);
+
+	/* React only to interrupts signaling a bulk_in transfer */
+	if (urb->actual_length == 4 && data[0] == 0x01) {
+		short old_rdtodo;
+
+		/* This is a announcement of coming bulk_ins. */
+		unsigned short size = ((unsigned short)data[3]<<8)+data[2]+3;
+
+		spin_lock_irqsave(&priv->lock, flags);
+
+		old_rdtodo = priv->rdtodo;
+
+		if (old_rdtodo > SHRT_MAX - size) {
+			dev_dbg(dev, "Too many bulk_in urbs to do.\n");
+			spin_unlock_irqrestore(&priv->lock, flags);
+			goto resubmit;
+		}
+
+		/* "+=" is probably more fault tolerant than "=" */
+		priv->rdtodo += size;
+
+		dev_dbg(dev, "%s - rdtodo: %d\n", __func__, priv->rdtodo);
+
+		spin_unlock_irqrestore(&priv->lock, flags);
+
+		if (!old_rdtodo) {
+			result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
+			if (result)
+				dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
+					__func__, result);
+			dev_dbg(dev, "%s - usb_submit_urb(read urb)\n", __func__);
+		}
+	}
+
+resubmit:
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
+	if (result)
+		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
+	dev_dbg(dev, "%s - usb_submit_urb(int urb)\n", __func__);
+}
+
+static void cyberjack_read_bulk_callback(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	struct cyberjack_private *priv = usb_get_serial_port_data(port);
+	struct device *dev = &port->dev;
+	unsigned char *data = urb->transfer_buffer;
+	unsigned long flags;
+	short todo;
+	int result;
+	int status = urb->status;
+
+	usb_serial_debug_data(dev, __func__, urb->actual_length, data);
+	if (status) {
+		dev_dbg(dev, "%s - nonzero read bulk status received: %d\n",
+			__func__, status);
+		return;
+	}
+
+	if (urb->actual_length) {
+		tty_insert_flip_string(&port->port, data, urb->actual_length);
+		tty_flip_buffer_push(&port->port);
+	}
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Reduce urbs to do by one. */
+	priv->rdtodo -= urb->actual_length;
+	/* Just to be sure */
+	if (priv->rdtodo < 0)
+		priv->rdtodo = 0;
+	todo = priv->rdtodo;
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	dev_dbg(dev, "%s - rdtodo: %d\n", __func__, todo);
+
+	/* Continue to read if we have still urbs to do. */
+	if (todo /* || (urb->actual_length==port->bulk_in_endpointAddress)*/) {
+		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
+		if (result)
+			dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
+				__func__, result);
+		dev_dbg(dev, "%s - usb_submit_urb(read urb)\n", __func__);
+	}
+}
+
+static void cyberjack_write_bulk_callback(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	struct cyberjack_private *priv = usb_get_serial_port_data(port);
+	struct device *dev = &port->dev;
+	int status = urb->status;
+	unsigned long flags;
+	bool resubmitted = false;
+
+	if (status) {
+		dev_dbg(dev, "%s - nonzero write bulk status received: %d\n",
+			__func__, status);
+		set_bit(0, &port->write_urbs_free);
+		return;
+	}
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* only do something if we have more data to send */
+	if (priv->wrfilled) {
+		int length, blksize, result;
+
+		dev_dbg(dev, "%s - transmitting data (frame n)\n", __func__);
+
+		length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?
+			port->bulk_out_size : (priv->wrfilled - priv->wrsent);
+
+		memcpy(port->write_urb->transfer_buffer,
+					priv->wrbuf + priv->wrsent, length);
+		priv->wrsent += length;
+
+		/* set up our urb */
+		port->write_urb->transfer_buffer_length = length;
+
+		/* send the data out the bulk port */
+		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
+		if (result) {
+			dev_err(dev, "%s - failed submitting write urb, error %d\n",
+				__func__, result);
+			/* Throw away data. No better idea what to do with it. */
+			priv->wrfilled = 0;
+			priv->wrsent = 0;
+			goto exit;
+		}
+
+		resubmitted = true;
+
+		dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent);
+		dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled);
+
+		blksize = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
+
+		if (priv->wrsent >= priv->wrfilled ||
+					priv->wrsent >= blksize) {
+			dev_dbg(dev, "%s - buffer cleaned\n", __func__);
+			memset(priv->wrbuf, 0, sizeof(priv->wrbuf));
+			priv->wrfilled = 0;
+			priv->wrsent = 0;
+		}
+	}
+
+exit:
+	spin_unlock_irqrestore(&priv->lock, flags);
+	if (!resubmitted)
+		set_bit(0, &port->write_urbs_free);
+	usb_serial_port_softint(port);
+}
+
+module_usb_serial_driver(serial_drivers, id_table);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");