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, 597 insertions, 0 deletions

diff --git a/drivers/parport/procfs.c b/drivers/parport/procfs.c
new file mode 100644
index 000000000..3880460e6
--- /dev/null
+++ b/drivers/parport/procfs.c
@@ -0,0 +1,597 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Sysctl interface for parport devices.
+ * 
+ * Authors: David Campbell
+ *          Tim Waugh <tim@cyberelk.demon.co.uk>
+ *          Philip Blundell <philb@gnu.org>
+ *          Andrea Arcangeli
+ *          Riccardo Facchetti <fizban@tin.it>
+ *
+ * based on work by Grant Guenther <grant@torque.net>
+ *              and Philip Blundell
+ *
+ * Cleaned up include files - Russell King <linux@arm.uk.linux.org>
+ */
+
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/parport.h>
+#include <linux/ctype.h>
+#include <linux/sysctl.h>
+#include <linux/device.h>
+
+#include <linux/uaccess.h>
+
+#if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
+
+#define PARPORT_MIN_TIMESLICE_VALUE 1ul 
+#define PARPORT_MAX_TIMESLICE_VALUE ((unsigned long) HZ)
+#define PARPORT_MIN_SPINTIME_VALUE 1
+#define PARPORT_MAX_SPINTIME_VALUE 1000
+
+static int do_active_device(const struct ctl_table *table, int write,
+		      void *result, size_t *lenp, loff_t *ppos)
+{
+	struct parport *port = (struct parport *)table->extra1;
+	char buffer[256];
+	struct pardevice *dev;
+	int len = 0;
+
+	if (write)		/* can't happen anyway */
+		return -EACCES;
+
+	if (*ppos) {
+		*lenp = 0;
+		return 0;
+	}
+	
+	for (dev = port->devices; dev ; dev = dev->next) {
+		if(dev == port->cad) {
+			len += scnprintf(buffer, sizeof(buffer), "%s\n", dev->name);
+		}
+	}
+
+	if(!len) {
+		len += scnprintf(buffer, sizeof(buffer), "%s\n", "none");
+	}
+
+	if (len > *lenp)
+		len = *lenp;
+	else
+		*lenp = len;
+
+	*ppos += len;
+	memcpy(result, buffer, len);
+	return 0;
+}
+
+#ifdef CONFIG_PARPORT_1284
+static int do_autoprobe(const struct ctl_table *table, int write,
+			void *result, size_t *lenp, loff_t *ppos)
+{
+	struct parport_device_info *info = table->extra2;
+	const char *str;
+	char buffer[256];
+	int len = 0;
+
+	if (write) /* permissions stop this */
+		return -EACCES;
+
+	if (*ppos) {
+		*lenp = 0;
+		return 0;
+	}
+	
+	if ((str = info->class_name) != NULL)
+		len += scnprintf (buffer + len, sizeof(buffer) - len, "CLASS:%s;\n", str);
+
+	if ((str = info->model) != NULL)
+		len += scnprintf (buffer + len, sizeof(buffer) - len, "MODEL:%s;\n", str);
+
+	if ((str = info->mfr) != NULL)
+		len += scnprintf (buffer + len, sizeof(buffer) - len, "MANUFACTURER:%s;\n", str);
+
+	if ((str = info->description) != NULL)
+		len += scnprintf (buffer + len, sizeof(buffer) - len, "DESCRIPTION:%s;\n", str);
+
+	if ((str = info->cmdset) != NULL)
+		len += scnprintf (buffer + len, sizeof(buffer) - len, "COMMAND SET:%s;\n", str);
+
+	if (len > *lenp)
+		len = *lenp;
+	else
+		*lenp = len;
+
+	*ppos += len;
+
+	memcpy(result, buffer, len);
+	return 0;
+}
+#endif /* IEEE1284.3 support. */
+
+static int do_hardware_base_addr(const struct ctl_table *table, int write,
+				 void *result, size_t *lenp, loff_t *ppos)
+{
+	struct parport *port = (struct parport *)table->extra1;
+	char buffer[64];
+	int len = 0;
+
+	if (*ppos) {
+		*lenp = 0;
+		return 0;
+	}
+
+	if (write) /* permissions prevent this anyway */
+		return -EACCES;
+
+	len += scnprintf (buffer, sizeof(buffer), "%lu\t%lu\n", port->base, port->base_hi);
+
+	if (len > *lenp)
+		len = *lenp;
+	else
+		*lenp = len;
+
+	*ppos += len;
+	memcpy(result, buffer, len);
+	return 0;
+}
+
+static int do_hardware_irq(const struct ctl_table *table, int write,
+			   void *result, size_t *lenp, loff_t *ppos)
+{
+	struct parport *port = (struct parport *)table->extra1;
+	char buffer[20];
+	int len = 0;
+
+	if (*ppos) {
+		*lenp = 0;
+		return 0;
+	}
+
+	if (write) /* permissions prevent this anyway */
+		return -EACCES;
+
+	len += scnprintf (buffer, sizeof(buffer), "%d\n", port->irq);
+
+	if (len > *lenp)
+		len = *lenp;
+	else
+		*lenp = len;
+
+	*ppos += len;
+	memcpy(result, buffer, len);
+	return 0;
+}
+
+static int do_hardware_dma(const struct ctl_table *table, int write,
+			   void *result, size_t *lenp, loff_t *ppos)
+{
+	struct parport *port = (struct parport *)table->extra1;
+	char buffer[20];
+	int len = 0;
+
+	if (*ppos) {
+		*lenp = 0;
+		return 0;
+	}
+
+	if (write) /* permissions prevent this anyway */
+		return -EACCES;
+
+	len += scnprintf (buffer, sizeof(buffer), "%d\n", port->dma);
+
+	if (len > *lenp)
+		len = *lenp;
+	else
+		*lenp = len;
+
+	*ppos += len;
+	memcpy(result, buffer, len);
+	return 0;
+}
+
+static int do_hardware_modes(const struct ctl_table *table, int write,
+			     void *result, size_t *lenp, loff_t *ppos)
+{
+	struct parport *port = (struct parport *)table->extra1;
+	char buffer[40];
+	int len = 0;
+
+	if (*ppos) {
+		*lenp = 0;
+		return 0;
+	}
+
+	if (write) /* permissions prevent this anyway */
+		return -EACCES;
+
+	{
+#define printmode(x)							\
+do {									\
+	if (port->modes & PARPORT_MODE_##x)				\
+		len += scnprintf(buffer + len, sizeof(buffer) - len, "%s%s", f++ ? "," : "", #x); \
+} while (0)
+		int f = 0;
+		printmode(PCSPP);
+		printmode(TRISTATE);
+		printmode(COMPAT);
+		printmode(EPP);
+		printmode(ECP);
+		printmode(DMA);
+#undef printmode
+	}
+	buffer[len++] = '\n';
+
+	if (len > *lenp)
+		len = *lenp;
+	else
+		*lenp = len;
+
+	*ppos += len;
+	memcpy(result, buffer, len);
+	return 0;
+}
+
+static const unsigned long parport_min_timeslice_value =
+PARPORT_MIN_TIMESLICE_VALUE;
+
+static const unsigned long parport_max_timeslice_value =
+PARPORT_MAX_TIMESLICE_VALUE;
+
+static const  int parport_min_spintime_value =
+PARPORT_MIN_SPINTIME_VALUE;
+
+static const int parport_max_spintime_value =
+PARPORT_MAX_SPINTIME_VALUE;
+
+
+struct parport_sysctl_table {
+	struct ctl_table_header *port_header;
+	struct ctl_table_header *devices_header;
+#ifdef CONFIG_PARPORT_1284
+	struct ctl_table vars[10];
+#else
+	struct ctl_table vars[5];
+#endif /* IEEE 1284 support */
+	struct ctl_table device_dir[1];
+};
+
+static const struct parport_sysctl_table parport_sysctl_template = {
+	.port_header = NULL,
+	.devices_header = NULL,
+	{
+		{
+			.procname	= "spintime",
+			.data		= NULL,
+			.maxlen		= sizeof(int),
+			.mode		= 0644,
+			.proc_handler	= proc_dointvec_minmax,
+			.extra1		= (void*) &parport_min_spintime_value,
+			.extra2		= (void*) &parport_max_spintime_value
+		},
+		{
+			.procname	= "base-addr",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_hardware_base_addr
+		},
+		{
+			.procname	= "irq",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_hardware_irq
+		},
+		{
+			.procname	= "dma",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_hardware_dma
+		},
+		{
+			.procname	= "modes",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_hardware_modes
+		},
+#ifdef CONFIG_PARPORT_1284
+		{
+			.procname	= "autoprobe",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_autoprobe
+		},
+		{
+			.procname	= "autoprobe0",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_autoprobe
+		},
+		{
+			.procname	= "autoprobe1",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_autoprobe
+		},
+		{
+			.procname	= "autoprobe2",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_autoprobe
+		},
+		{
+			.procname	= "autoprobe3",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_autoprobe
+		},
+#endif /* IEEE 1284 support */
+	},
+	{
+		{
+			.procname	= "active",
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0444,
+			.proc_handler	= do_active_device
+		},
+	},
+};
+
+struct parport_device_sysctl_table
+{
+	struct ctl_table_header *sysctl_header;
+	struct ctl_table vars[1];
+	struct ctl_table device_dir[1];
+};
+
+static const struct parport_device_sysctl_table
+parport_device_sysctl_template = {
+	.sysctl_header = NULL,
+	{
+		{
+			.procname 	= "timeslice",
+			.data		= NULL,
+			.maxlen		= sizeof(unsigned long),
+			.mode		= 0644,
+			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+			.extra1		= (void*) &parport_min_timeslice_value,
+			.extra2		= (void*) &parport_max_timeslice_value
+		},
+	},
+	{
+		{
+			.procname	= NULL,
+			.data		= NULL,
+			.maxlen		= 0,
+			.mode		= 0555,
+		},
+	}
+};
+
+struct parport_default_sysctl_table
+{
+	struct ctl_table_header *sysctl_header;
+	struct ctl_table vars[2];
+};
+
+static struct parport_default_sysctl_table
+parport_default_sysctl_table = {
+	.sysctl_header	= NULL,
+	{
+		{
+			.procname	= "timeslice",
+			.data		= &parport_default_timeslice,
+			.maxlen		= sizeof(parport_default_timeslice),
+			.mode		= 0644,
+			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
+			.extra1		= (void*) &parport_min_timeslice_value,
+			.extra2		= (void*) &parport_max_timeslice_value
+		},
+		{
+			.procname	= "spintime",
+			.data		= &parport_default_spintime,
+			.maxlen		= sizeof(parport_default_spintime),
+			.mode		= 0644,
+			.proc_handler	= proc_dointvec_minmax,
+			.extra1		= (void*) &parport_min_spintime_value,
+			.extra2		= (void*) &parport_max_spintime_value
+		},
+	}
+};
+
+int parport_proc_register(struct parport *port)
+{
+	struct parport_sysctl_table *t;
+	char *tmp_dir_path;
+	int i, err = 0;
+
+	t = kmemdup(&parport_sysctl_template, sizeof(*t), GFP_KERNEL);
+	if (t == NULL)
+		return -ENOMEM;
+
+	t->device_dir[0].extra1 = port;
+
+	t->vars[0].data = &port->spintime;
+	for (i = 0; i < 5; i++) {
+		t->vars[i].extra1 = port;
+#ifdef CONFIG_PARPORT_1284
+		t->vars[5 + i].extra2 = &port->probe_info[i];
+#endif /* IEEE 1284 support */
+	}
+
+	tmp_dir_path = kasprintf(GFP_KERNEL, "dev/parport/%s/devices", port->name);
+	if (!tmp_dir_path) {
+		err = -ENOMEM;
+		goto exit_free_t;
+	}
+
+	t->devices_header = register_sysctl(tmp_dir_path, t->device_dir);
+	if (t->devices_header == NULL) {
+		err = -ENOENT;
+		goto  exit_free_tmp_dir_path;
+	}
+
+	kfree(tmp_dir_path);
+
+	tmp_dir_path = kasprintf(GFP_KERNEL, "dev/parport/%s", port->name);
+	if (!tmp_dir_path) {
+		err = -ENOMEM;
+		goto unregister_devices_h;
+	}
+
+	t->port_header = register_sysctl(tmp_dir_path, t->vars);
+	if (t->port_header == NULL) {
+		err = -ENOENT;
+		goto unregister_devices_h;
+	}
+
+	port->sysctl_table = t;
+
+	kfree(tmp_dir_path);
+	return 0;
+
+unregister_devices_h:
+	unregister_sysctl_table(t->devices_header);
+
+exit_free_tmp_dir_path:
+	kfree(tmp_dir_path);
+
+exit_free_t:
+	kfree(t);
+	return err;
+}
+
+int parport_proc_unregister(struct parport *port)
+{
+	if (port->sysctl_table) {
+		struct parport_sysctl_table *t = port->sysctl_table;
+		port->sysctl_table = NULL;
+		unregister_sysctl_table(t->devices_header);
+		unregister_sysctl_table(t->port_header);
+		kfree(t);
+	}
+	return 0;
+}
+
+int parport_device_proc_register(struct pardevice *device)
+{
+	struct parport_device_sysctl_table *t;
+	struct parport * port = device->port;
+	char *tmp_dir_path;
+	int err = 0;
+	
+	t = kmemdup(&parport_device_sysctl_template, sizeof(*t), GFP_KERNEL);
+	if (t == NULL)
+		return -ENOMEM;
+
+	/* Allocate a buffer for two paths: dev/parport/PORT/devices/DEVICE. */
+	tmp_dir_path = kasprintf(GFP_KERNEL, "dev/parport/%s/devices/%s", port->name, device->name);
+	if (!tmp_dir_path) {
+		err = -ENOMEM;
+		goto exit_free_t;
+	}
+
+	t->vars[0].data = &device->timeslice;
+
+	t->sysctl_header = register_sysctl(tmp_dir_path, t->vars);
+	if (t->sysctl_header == NULL) {
+		kfree(t);
+		t = NULL;
+	}
+	device->sysctl_table = t;
+
+	kfree(tmp_dir_path);
+	return 0;
+
+exit_free_t:
+	kfree(t);
+
+	return err;
+}
+
+int parport_device_proc_unregister(struct pardevice *device)
+{
+	if (device->sysctl_table) {
+		struct parport_device_sysctl_table *t = device->sysctl_table;
+		device->sysctl_table = NULL;
+		unregister_sysctl_table(t->sysctl_header);
+		kfree(t);
+	}
+	return 0;
+}
+
+static int __init parport_default_proc_register(void)
+{
+	int ret;
+
+	parport_default_sysctl_table.sysctl_header =
+		register_sysctl("dev/parport/default", parport_default_sysctl_table.vars);
+	if (!parport_default_sysctl_table.sysctl_header)
+		return -ENOMEM;
+	ret = parport_bus_init();
+	if (ret) {
+		unregister_sysctl_table(parport_default_sysctl_table.
+					sysctl_header);
+		return ret;
+	}
+	return 0;
+}
+
+static void __exit parport_default_proc_unregister(void)
+{
+	if (parport_default_sysctl_table.sysctl_header) {
+		unregister_sysctl_table(parport_default_sysctl_table.
+					sysctl_header);
+		parport_default_sysctl_table.sysctl_header = NULL;
+	}
+	parport_bus_exit();
+}
+
+#else /* no sysctl or no procfs*/
+
+int parport_proc_register(struct parport *pp)
+{
+	return 0;
+}
+
+int parport_proc_unregister(struct parport *pp)
+{
+	return 0;
+}
+
+int parport_device_proc_register(struct pardevice *device)
+{
+	return 0;
+}
+
+int parport_device_proc_unregister(struct pardevice *device)
+{
+	return 0;
+}
+
+static int __init parport_default_proc_register (void)
+{
+	return parport_bus_init();
+}
+
+static void __exit parport_default_proc_unregister (void)
+{
+	parport_bus_exit();
+}
+#endif
+
+subsys_initcall(parport_default_proc_register)
+module_exit(parport_default_proc_unregister)