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, 476 insertions, 0 deletions

diff --git a/drivers/usb/misc/lvstest.c b/drivers/usb/misc/lvstest.c
new file mode 100644
index 000000000..9b6e10177
--- /dev/null
+++ b/drivers/usb/misc/lvstest.c
@@ -0,0 +1,476 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * drivers/usb/misc/lvstest.c
+ *
+ * Test pattern generation for Link Layer Validation System Tests
+ *
+ * Copyright (C) 2014 ST Microelectronics
+ * Pratyush Anand <pratyush.anand@gmail.com>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/ch11.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/phy.h>
+
+struct lvs_rh {
+	/* root hub interface */
+	struct usb_interface *intf;
+	/* if lvs device connected */
+	bool present;
+	/* port no at which lvs device is present */
+	int portnum;
+	/* urb buffer */
+	u8 buffer[8];
+	/* class descriptor */
+	struct usb_hub_descriptor descriptor;
+	/* urb for polling interrupt pipe */
+	struct urb *urb;
+	/* LVH RH work */
+	struct work_struct	rh_work;
+	/* RH port status */
+	struct usb_port_status port_status;
+};
+
+static struct usb_device *create_lvs_device(struct usb_interface *intf)
+{
+	struct usb_device *udev, *hdev;
+	struct usb_hcd *hcd;
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+
+	if (!lvs->present) {
+		dev_err(&intf->dev, "No LVS device is present\n");
+		return NULL;
+	}
+
+	hdev = interface_to_usbdev(intf);
+	hcd = bus_to_hcd(hdev->bus);
+
+	udev = usb_alloc_dev(hdev, hdev->bus, lvs->portnum);
+	if (!udev) {
+		dev_err(&intf->dev, "Could not allocate lvs udev\n");
+		return NULL;
+	}
+	udev->speed = USB_SPEED_SUPER;
+	udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
+	usb_set_device_state(udev, USB_STATE_DEFAULT);
+
+	if (hcd->driver->enable_device) {
+		if (hcd->driver->enable_device(hcd, udev) < 0) {
+			dev_err(&intf->dev, "Failed to enable\n");
+			usb_put_dev(udev);
+			return NULL;
+		}
+	}
+
+	return udev;
+}
+
+static void destroy_lvs_device(struct usb_device *udev)
+{
+	struct usb_device *hdev = udev->parent;
+	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
+
+	if (hcd->driver->free_dev)
+		hcd->driver->free_dev(hcd, udev);
+
+	usb_put_dev(udev);
+}
+
+static int lvs_rh_clear_port_feature(struct usb_device *hdev,
+		int port1, int feature)
+{
+	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
+		NULL, 0, 1000);
+}
+
+static int lvs_rh_set_port_feature(struct usb_device *hdev,
+		int port1, int feature)
+{
+	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
+		NULL, 0, 1000);
+}
+
+static ssize_t u3_entry_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	struct usb_device *udev;
+	int ret;
+
+	udev = create_lvs_device(intf);
+	if (!udev) {
+		dev_err(dev, "failed to create lvs device\n");
+		return -ENOMEM;
+	}
+
+	ret = lvs_rh_set_port_feature(hdev, lvs->portnum,
+			USB_PORT_FEAT_SUSPEND);
+	if (ret < 0)
+		dev_err(dev, "can't issue U3 entry %d\n", ret);
+
+	destroy_lvs_device(udev);
+
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+static DEVICE_ATTR_WO(u3_entry);
+
+static ssize_t u3_exit_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	struct usb_device *udev;
+	int ret;
+
+	udev = create_lvs_device(intf);
+	if (!udev) {
+		dev_err(dev, "failed to create lvs device\n");
+		return -ENOMEM;
+	}
+
+	ret = lvs_rh_clear_port_feature(hdev, lvs->portnum,
+			USB_PORT_FEAT_SUSPEND);
+	if (ret < 0)
+		dev_err(dev, "can't issue U3 exit %d\n", ret);
+
+	destroy_lvs_device(udev);
+
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+static DEVICE_ATTR_WO(u3_exit);
+
+static ssize_t hot_reset_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	int ret;
+
+	ret = lvs_rh_set_port_feature(hdev, lvs->portnum,
+			USB_PORT_FEAT_RESET);
+	if (ret < 0) {
+		dev_err(dev, "can't issue hot reset %d\n", ret);
+		return ret;
+	}
+
+	return count;
+}
+static DEVICE_ATTR_WO(hot_reset);
+
+static ssize_t warm_reset_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	int ret;
+
+	ret = lvs_rh_set_port_feature(hdev, lvs->portnum,
+			USB_PORT_FEAT_BH_PORT_RESET);
+	if (ret < 0) {
+		dev_err(dev, "can't issue warm reset %d\n", ret);
+		return ret;
+	}
+
+	return count;
+}
+static DEVICE_ATTR_WO(warm_reset);
+
+static ssize_t u2_timeout_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	unsigned long val;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret < 0) {
+		dev_err(dev, "couldn't parse string %d\n", ret);
+		return ret;
+	}
+
+	if (val > 127)
+		return -EINVAL;
+
+	ret = lvs_rh_set_port_feature(hdev, lvs->portnum | (val << 8),
+			USB_PORT_FEAT_U2_TIMEOUT);
+	if (ret < 0) {
+		dev_err(dev, "Error %d while setting U2 timeout %ld\n", ret, val);
+		return ret;
+	}
+
+	return count;
+}
+static DEVICE_ATTR_WO(u2_timeout);
+
+static ssize_t u1_timeout_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	unsigned long val;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret < 0) {
+		dev_err(dev, "couldn't parse string %d\n", ret);
+		return ret;
+	}
+
+	if (val > 127)
+		return -EINVAL;
+
+	ret = lvs_rh_set_port_feature(hdev, lvs->portnum | (val << 8),
+			USB_PORT_FEAT_U1_TIMEOUT);
+	if (ret < 0) {
+		dev_err(dev, "Error %d while setting U1 timeout %ld\n", ret, val);
+		return ret;
+	}
+
+	return count;
+}
+static DEVICE_ATTR_WO(u1_timeout);
+
+static ssize_t get_dev_desc_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *udev;
+	struct usb_device_descriptor *descriptor;
+	int ret;
+
+	descriptor = kmalloc_obj(*descriptor);
+	if (!descriptor)
+		return -ENOMEM;
+
+	udev = create_lvs_device(intf);
+	if (!udev) {
+		dev_err(dev, "failed to create lvs device\n");
+		ret = -ENOMEM;
+		goto free_desc;
+	}
+
+	ret = usb_control_msg(udev, (PIPE_CONTROL << 30) | USB_DIR_IN,
+			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, USB_DT_DEVICE << 8,
+			0, descriptor, sizeof(*descriptor),
+			USB_CTRL_GET_TIMEOUT);
+	if (ret < 0)
+		dev_err(dev, "can't read device descriptor %d\n", ret);
+
+	destroy_lvs_device(udev);
+
+free_desc:
+	kfree(descriptor);
+
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+static DEVICE_ATTR_WO(get_dev_desc);
+
+static ssize_t enable_compliance_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+	int ret;
+
+	ret = lvs_rh_set_port_feature(hdev,
+			lvs->portnum | USB_SS_PORT_LS_COMP_MOD << 3,
+			USB_PORT_FEAT_LINK_STATE);
+	if (ret < 0) {
+		dev_err(dev, "can't enable compliance mode %d\n", ret);
+		return ret;
+	}
+
+	return count;
+}
+static DEVICE_ATTR_WO(enable_compliance);
+
+static struct attribute *lvs_attrs[] = {
+	&dev_attr_get_dev_desc.attr,
+	&dev_attr_u1_timeout.attr,
+	&dev_attr_u2_timeout.attr,
+	&dev_attr_hot_reset.attr,
+	&dev_attr_warm_reset.attr,
+	&dev_attr_u3_entry.attr,
+	&dev_attr_u3_exit.attr,
+	&dev_attr_enable_compliance.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(lvs);
+
+static void lvs_rh_work(struct work_struct *work)
+{
+	struct lvs_rh *lvs = container_of(work, struct lvs_rh, rh_work);
+	struct usb_interface *intf = lvs->intf;
+	struct usb_device *hdev = interface_to_usbdev(intf);
+	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
+	struct usb_hub_descriptor *descriptor = &lvs->descriptor;
+	struct usb_port_status *port_status = &lvs->port_status;
+	int i, ret = 0;
+	u16 portchange;
+
+	/* Examine each root port */
+	for (i = 1; i <= descriptor->bNbrPorts; i++) {
+		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, i,
+			port_status, sizeof(*port_status), 1000);
+		if (ret < 4)
+			continue;
+
+		portchange = le16_to_cpu(port_status->wPortChange);
+
+		if (portchange & USB_PORT_STAT_C_LINK_STATE)
+			lvs_rh_clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_PORT_LINK_STATE);
+		if (portchange & USB_PORT_STAT_C_ENABLE)
+			lvs_rh_clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_ENABLE);
+		if (portchange & USB_PORT_STAT_C_RESET)
+			lvs_rh_clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_RESET);
+		if (portchange & USB_PORT_STAT_C_BH_RESET)
+			lvs_rh_clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_BH_PORT_RESET);
+		if (portchange & USB_PORT_STAT_C_CONNECTION) {
+			lvs_rh_clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_CONNECTION);
+
+			if (le16_to_cpu(port_status->wPortStatus) &
+					USB_PORT_STAT_CONNECTION) {
+				lvs->present = true;
+				lvs->portnum = i;
+				if (hcd->usb_phy)
+					usb_phy_notify_connect(hcd->usb_phy,
+							USB_SPEED_SUPER);
+			} else {
+				lvs->present = false;
+				if (hcd->usb_phy)
+					usb_phy_notify_disconnect(hcd->usb_phy,
+							USB_SPEED_SUPER);
+			}
+			break;
+		}
+	}
+
+	ret = usb_submit_urb(lvs->urb, GFP_KERNEL);
+	if (ret != 0 && ret != -ENODEV && ret != -EPERM)
+		dev_err(&intf->dev, "urb resubmit error %d\n", ret);
+}
+
+static void lvs_rh_irq(struct urb *urb)
+{
+	struct lvs_rh *lvs = urb->context;
+
+	schedule_work(&lvs->rh_work);
+}
+
+static int lvs_rh_probe(struct usb_interface *intf,
+		const struct usb_device_id *id)
+{
+	struct usb_device *hdev;
+	struct usb_host_interface *desc;
+	struct usb_endpoint_descriptor *endpoint;
+	struct lvs_rh *lvs;
+	unsigned int pipe;
+	int ret, maxp;
+
+	hdev = interface_to_usbdev(intf);
+	desc = intf->cur_altsetting;
+
+	ret = usb_find_int_in_endpoint(desc, &endpoint);
+	if (ret)
+		return ret;
+
+	/* valid only for SS root hub */
+	if (hdev->descriptor.bDeviceProtocol != USB_HUB_PR_SS || hdev->parent) {
+		dev_err(&intf->dev, "Bind LVS driver with SS root Hub only\n");
+		return -EINVAL;
+	}
+
+	lvs = devm_kzalloc(&intf->dev, sizeof(*lvs), GFP_KERNEL);
+	if (!lvs)
+		return -ENOMEM;
+
+	lvs->intf = intf;
+	usb_set_intfdata(intf, lvs);
+
+	/* how many number of ports this root hub has */
+	ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
+			USB_DT_SS_HUB << 8, 0, &lvs->descriptor,
+			USB_DT_SS_HUB_SIZE, USB_CTRL_GET_TIMEOUT);
+	if (ret < (USB_DT_HUB_NONVAR_SIZE + 2)) {
+		dev_err(&hdev->dev, "wrong root hub descriptor read %d\n", ret);
+		return ret < 0 ? ret : -EINVAL;
+	}
+
+	/* submit urb to poll interrupt endpoint */
+	lvs->urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!lvs->urb)
+		return -ENOMEM;
+
+	INIT_WORK(&lvs->rh_work, lvs_rh_work);
+
+	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
+	maxp = usb_maxpacket(hdev, pipe);
+	usb_fill_int_urb(lvs->urb, hdev, pipe, &lvs->buffer[0], maxp,
+			lvs_rh_irq, lvs, endpoint->bInterval);
+
+	ret = usb_submit_urb(lvs->urb, GFP_KERNEL);
+	if (ret < 0) {
+		dev_err(&intf->dev, "couldn't submit lvs urb %d\n", ret);
+		goto free_urb;
+	}
+
+	return ret;
+
+free_urb:
+	usb_free_urb(lvs->urb);
+	return ret;
+}
+
+static void lvs_rh_disconnect(struct usb_interface *intf)
+{
+	struct lvs_rh *lvs = usb_get_intfdata(intf);
+
+	usb_poison_urb(lvs->urb); /* used in scheduled work */
+	flush_work(&lvs->rh_work);
+	usb_free_urb(lvs->urb);
+}
+
+static struct usb_driver lvs_driver = {
+	.name =		"lvs",
+	.probe =	lvs_rh_probe,
+	.disconnect =	lvs_rh_disconnect,
+	.dev_groups =	lvs_groups,
+};
+
+module_usb_driver(lvs_driver);
+
+MODULE_DESCRIPTION("Link Layer Validation System Driver");
+MODULE_LICENSE("GPL");