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, 294 insertions, 0 deletions

diff --git a/drivers/input/sparse-keymap.c b/drivers/input/sparse-keymap.c
new file mode 100644
index 000000000..164f8fcfd
--- /dev/null
+++ b/drivers/input/sparse-keymap.c
@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Generic support for sparse keymaps
+ *
+ * Copyright (c) 2009 Dmitry Torokhov
+ *
+ * Derived from wistron button driver:
+ * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
+ * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
+ * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
+ */
+
+#include <linux/export.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
+MODULE_DESCRIPTION("Generic support for sparse keymaps");
+MODULE_LICENSE("GPL v2");
+
+static unsigned int sparse_keymap_get_key_index(struct input_dev *dev,
+						const struct key_entry *k)
+{
+	struct key_entry *key;
+	unsigned int idx = 0;
+
+	for (key = dev->keycode; key->type != KE_END; key++) {
+		if (key->type == KE_KEY) {
+			if (key == k)
+				break;
+			idx++;
+		}
+	}
+
+	return idx;
+}
+
+static struct key_entry *sparse_keymap_entry_by_index(struct input_dev *dev,
+						      unsigned int index)
+{
+	struct key_entry *key;
+	unsigned int key_cnt = 0;
+
+	for (key = dev->keycode; key->type != KE_END; key++)
+		if (key->type == KE_KEY)
+			if (key_cnt++ == index)
+				return key;
+
+	return NULL;
+}
+
+/**
+ * sparse_keymap_entry_from_scancode - perform sparse keymap lookup
+ * @dev: Input device using sparse keymap
+ * @code: Scan code
+ *
+ * This function is used to perform &struct key_entry lookup in an
+ * input device using sparse keymap.
+ */
+struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev,
+						    unsigned int code)
+{
+	struct key_entry *key;
+
+	for (key = dev->keycode; key->type != KE_END; key++)
+		if (code == key->code)
+			return key;
+
+	return NULL;
+}
+EXPORT_SYMBOL(sparse_keymap_entry_from_scancode);
+
+/**
+ * sparse_keymap_entry_from_keycode - perform sparse keymap lookup
+ * @dev: Input device using sparse keymap
+ * @keycode: Key code
+ *
+ * This function is used to perform &struct key_entry lookup in an
+ * input device using sparse keymap.
+ */
+struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev,
+						   unsigned int keycode)
+{
+	struct key_entry *key;
+
+	for (key = dev->keycode; key->type != KE_END; key++)
+		if (key->type == KE_KEY && keycode == key->keycode)
+			return key;
+
+	return NULL;
+}
+EXPORT_SYMBOL(sparse_keymap_entry_from_keycode);
+
+static struct key_entry *sparse_keymap_locate(struct input_dev *dev,
+					const struct input_keymap_entry *ke)
+{
+	struct key_entry *key;
+	unsigned int scancode;
+
+	if (ke->flags & INPUT_KEYMAP_BY_INDEX)
+		key = sparse_keymap_entry_by_index(dev, ke->index);
+	else if (input_scancode_to_scalar(ke, &scancode) == 0)
+		key = sparse_keymap_entry_from_scancode(dev, scancode);
+	else
+		key = NULL;
+
+	return key;
+}
+
+static int sparse_keymap_getkeycode(struct input_dev *dev,
+				    struct input_keymap_entry *ke)
+{
+	const struct key_entry *key;
+
+	if (dev->keycode) {
+		key = sparse_keymap_locate(dev, ke);
+		if (key && key->type == KE_KEY) {
+			ke->keycode = key->keycode;
+			if (!(ke->flags & INPUT_KEYMAP_BY_INDEX))
+				ke->index =
+					sparse_keymap_get_key_index(dev, key);
+			ke->len = sizeof(key->code);
+			memcpy(ke->scancode, &key->code, sizeof(key->code));
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int sparse_keymap_setkeycode(struct input_dev *dev,
+				    const struct input_keymap_entry *ke,
+				    unsigned int *old_keycode)
+{
+	struct key_entry *key;
+
+	if (dev->keycode) {
+		key = sparse_keymap_locate(dev, ke);
+		if (key && key->type == KE_KEY) {
+			*old_keycode = key->keycode;
+			key->keycode = ke->keycode;
+			set_bit(ke->keycode, dev->keybit);
+			if (!sparse_keymap_entry_from_keycode(dev, *old_keycode))
+				clear_bit(*old_keycode, dev->keybit);
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+/**
+ * sparse_keymap_setup - set up sparse keymap for an input device
+ * @dev: Input device
+ * @keymap: Keymap in form of array of &key_entry structures ending
+ *	with %KE_END type entry
+ * @setup: Function that can be used to adjust keymap entries
+ *	depending on device's needs, may be %NULL
+ *
+ * The function calculates size and allocates copy of the original
+ * keymap after which sets up input device event bits appropriately.
+ * The allocated copy of the keymap is automatically freed when it
+ * is no longer needed.
+ */
+int sparse_keymap_setup(struct input_dev *dev,
+			const struct key_entry *keymap,
+			int (*setup)(struct input_dev *, struct key_entry *))
+{
+	size_t map_size = 1; /* to account for the last KE_END entry */
+	const struct key_entry *e;
+	struct key_entry *map, *entry;
+	int i;
+	int error;
+
+	for (e = keymap; e->type != KE_END; e++)
+		map_size++;
+
+	map = devm_kmemdup_array(&dev->dev, keymap, map_size, sizeof(*keymap), GFP_KERNEL);
+	if (!map)
+		return -ENOMEM;
+
+	for (i = 0; i < map_size; i++) {
+		entry = &map[i];
+
+		if (setup) {
+			error = setup(dev, entry);
+			if (error)
+				return error;
+		}
+
+		switch (entry->type) {
+		case KE_KEY:
+			__set_bit(EV_KEY, dev->evbit);
+			__set_bit(entry->keycode, dev->keybit);
+			break;
+
+		case KE_SW:
+		case KE_VSW:
+			__set_bit(EV_SW, dev->evbit);
+			__set_bit(entry->sw.code, dev->swbit);
+			break;
+		}
+	}
+
+	if (test_bit(EV_KEY, dev->evbit)) {
+		__set_bit(KEY_UNKNOWN, dev->keybit);
+		__set_bit(EV_MSC, dev->evbit);
+		__set_bit(MSC_SCAN, dev->mscbit);
+	}
+
+	dev->keycode = map;
+	dev->keycodemax = map_size;
+	dev->getkeycode = sparse_keymap_getkeycode;
+	dev->setkeycode = sparse_keymap_setkeycode;
+
+	return 0;
+}
+EXPORT_SYMBOL(sparse_keymap_setup);
+
+/**
+ * sparse_keymap_report_entry - report event corresponding to given key entry
+ * @dev: Input device for which event should be reported
+ * @ke: key entry describing event
+ * @value: Value that should be reported (ignored by %KE_SW entries)
+ * @autorelease: Signals whether release event should be emitted for %KE_KEY
+ *	entries right after reporting press event, ignored by all other
+ *	entries
+ *
+ * This function is used to report input event described by given
+ * &struct key_entry.
+ */
+void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *ke,
+				unsigned int value, bool autorelease)
+{
+	switch (ke->type) {
+	case KE_KEY:
+		input_event(dev, EV_MSC, MSC_SCAN, ke->code);
+		input_report_key(dev, ke->keycode, value);
+		input_sync(dev);
+		if (value && autorelease) {
+			input_report_key(dev, ke->keycode, 0);
+			input_sync(dev);
+		}
+		break;
+
+	case KE_SW:
+		value = ke->sw.value;
+		fallthrough;
+
+	case KE_VSW:
+		input_report_switch(dev, ke->sw.code, value);
+		input_sync(dev);
+		break;
+	}
+}
+EXPORT_SYMBOL(sparse_keymap_report_entry);
+
+/**
+ * sparse_keymap_report_event - report event corresponding to given scancode
+ * @dev: Input device using sparse keymap
+ * @code: Scan code
+ * @value: Value that should be reported (ignored by %KE_SW entries)
+ * @autorelease: Signals whether release event should be emitted for %KE_KEY
+ *	entries right after reporting press event, ignored by all other
+ *	entries
+ *
+ * This function is used to perform lookup in an input device using sparse
+ * keymap and report corresponding event. Returns %true if lookup was
+ * successful and %false otherwise.
+ */
+bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code,
+				unsigned int value, bool autorelease)
+{
+	const struct key_entry *ke =
+		sparse_keymap_entry_from_scancode(dev, code);
+	struct key_entry unknown_ke;
+
+	if (ke) {
+		sparse_keymap_report_entry(dev, ke, value, autorelease);
+		return true;
+	}
+
+	/* Report an unknown key event as a debugging aid */
+	unknown_ke.type = KE_KEY;
+	unknown_ke.code = code;
+	unknown_ke.keycode = KEY_UNKNOWN;
+	sparse_keymap_report_entry(dev, &unknown_ke, value, true);
+
+	return false;
+}
+EXPORT_SYMBOL(sparse_keymap_report_event);
+