Merging upstream version 6.10.6.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 52 insertions, 22 deletions

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 749a182dab..8edab43580 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1573,6 +1573,29 @@ static inline void *event_file_data(struct file *filp)
 extern struct mutex event_mutex;
 extern struct list_head ftrace_events;
 
+/*
+ * When the trace_event_file is the filp->i_private pointer,
+ * it must be taken under the event_mutex lock, and then checked
+ * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
+ * data pointed to by the trace_event_file can not be trusted.
+ *
+ * Use the event_file_file() to access the trace_event_file from
+ * the filp the first time under the event_mutex and check for
+ * NULL. If it is needed to be retrieved again and the event_mutex
+ * is still held, then the event_file_data() can be used and it
+ * is guaranteed to be valid.
+ */
+static inline struct trace_event_file *event_file_file(struct file *filp)
+{
+	struct trace_event_file *file;
+
+	lockdep_assert_held(&event_mutex);
+	file = READ_ONCE(file_inode(filp)->i_private);
+	if (!file || file->flags & EVENT_FILE_FL_FREED)
+		return NULL;
+	return file;
+}
+
 extern const struct file_operations event_trigger_fops;
 extern const struct file_operations event_hist_fops;
 extern const struct file_operations event_hist_debug_fops;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 6ef29eba90..f08fbaf8ca 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1386,12 +1386,12 @@ event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
 	char buf[4] = "0";
 
 	mutex_lock(&event_mutex);
-	file = event_file_data(filp);
+	file = event_file_file(filp);
 	if (likely(file))
 		flags = file->flags;
 	mutex_unlock(&event_mutex);
 
-	if (!file || flags & EVENT_FILE_FL_FREED)
+	if (!file)
 		return -ENODEV;
 
 	if (flags & EVENT_FILE_FL_ENABLED &&
@@ -1424,8 +1424,8 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 	case 1:
 		ret = -ENODEV;
 		mutex_lock(&event_mutex);
-		file = event_file_data(filp);
-		if (likely(file && !(file->flags & EVENT_FILE_FL_FREED))) {
+		file = event_file_file(filp);
+		if (likely(file)) {
 			ret = tracing_update_buffers(file->tr);
 			if (ret < 0) {
 				mutex_unlock(&event_mutex);
@@ -1540,7 +1540,8 @@ enum {
 
 static void *f_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	struct trace_event_call *call = event_file_data(m->private);
+	struct trace_event_file *file = event_file_data(m->private);
+	struct trace_event_call *call = file->event_call;
 	struct list_head *common_head = &ftrace_common_fields;
 	struct list_head *head = trace_get_fields(call);
 	struct list_head *node = v;
@@ -1572,7 +1573,8 @@ static void *f_next(struct seq_file *m, void *v, loff_t *pos)
 
 static int f_show(struct seq_file *m, void *v)
 {
-	struct trace_event_call *call = event_file_data(m->private);
+	struct trace_event_file *file = event_file_data(m->private);
+	struct trace_event_call *call = file->event_call;
 	struct ftrace_event_field *field;
 	const char *array_descriptor;
 
@@ -1627,12 +1629,14 @@ static int f_show(struct seq_file *m, void *v)
 
 static void *f_start(struct seq_file *m, loff_t *pos)
 {
+	struct trace_event_file *file;
 	void *p = (void *)FORMAT_HEADER;
 	loff_t l = 0;
 
 	/* ->stop() is called even if ->start() fails */
 	mutex_lock(&event_mutex);
-	if (!event_file_data(m->private))
+	file = event_file_file(m->private);
+	if (!file)
 		return ERR_PTR(-ENODEV);
 
 	while (l < *pos && p)
@@ -1706,8 +1710,8 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
 	trace_seq_init(s);
 
 	mutex_lock(&event_mutex);
-	file = event_file_data(filp);
-	if (file && !(file->flags & EVENT_FILE_FL_FREED))
+	file = event_file_file(filp);
+	if (file)
 		print_event_filter(file, s);
 	mutex_unlock(&event_mutex);
 
@@ -1736,9 +1740,13 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
 		return PTR_ERR(buf);
 
 	mutex_lock(&event_mutex);
-	file = event_file_data(filp);
-	if (file)
-		err = apply_event_filter(file, buf);
+	file = event_file_file(filp);
+	if (file) {
+		if (file->flags & EVENT_FILE_FL_FREED)
+			err = -ENODEV;
+		else
+			err = apply_event_filter(file, buf);
+	}
 	mutex_unlock(&event_mutex);
 
 	kfree(buf);
@@ -2485,7 +2493,6 @@ static int event_callback(const char *name, umode_t *mode, void **data,
 	if (strcmp(name, "format") == 0) {
 		*mode = TRACE_MODE_READ;
 		*fops = &ftrace_event_format_fops;
-		*data = call;
 		return 1;
 	}
 
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 6ece1308d3..5f9119eb7c 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -5601,7 +5601,7 @@ static int hist_show(struct seq_file *m, void *v)
 
 	mutex_lock(&event_mutex);
 
-	event_file = event_file_data(m->private);
+	event_file = event_file_file(m->private);
 	if (unlikely(!event_file)) {
 		ret = -ENODEV;
 		goto out_unlock;
@@ -5880,7 +5880,7 @@ static int hist_debug_show(struct seq_file *m, void *v)
 
 	mutex_lock(&event_mutex);
 
-	event_file = event_file_data(m->private);
+	event_file = event_file_file(m->private);
 	if (unlikely(!event_file)) {
 		ret = -ENODEV;
 		goto out_unlock;
diff --git a/kernel/trace/trace_events_inject.c b/kernel/trace/trace_events_inject.c
index 8650562bda..a8f076809d 100644
--- a/kernel/trace/trace_events_inject.c
+++ b/kernel/trace/trace_events_inject.c
@@ -299,7 +299,7 @@ event_inject_write(struct file *filp, const char __user *ubuf, size_t cnt,
 	strim(buf);
 
 	mutex_lock(&event_mutex);
-	file = event_file_data(filp);
+	file = event_file_file(filp);
 	if (file) {
 		call = file->event_call;
 		size = parse_entry(buf, call, &entry);
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 4bec043c86..a5e3d6acf1 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -159,7 +159,7 @@ static void *trigger_start(struct seq_file *m, loff_t *pos)
 
 	/* ->stop() is called even if ->start() fails */
 	mutex_lock(&event_mutex);
-	event_file = event_file_data(m->private);
+	event_file = event_file_file(m->private);
 	if (unlikely(!event_file))
 		return ERR_PTR(-ENODEV);
 
@@ -213,7 +213,7 @@ static int event_trigger_regex_open(struct inode *inode, struct file *file)
 
 	mutex_lock(&event_mutex);
 
-	if (unlikely(!event_file_data(file))) {
+	if (unlikely(!event_file_file(file))) {
 		mutex_unlock(&event_mutex);
 		return -ENODEV;
 	}
@@ -293,7 +293,7 @@ static ssize_t event_trigger_regex_write(struct file *file,
 	strim(buf);
 
 	mutex_lock(&event_mutex);
-	event_file = event_file_data(file);
+	event_file = event_file_file(file);
 	if (unlikely(!event_file)) {
 		mutex_unlock(&event_mutex);
 		kfree(buf);
diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c
index a4dcf0f243..3a56e7c8aa 100644
--- a/kernel/trace/tracing_map.c
+++ b/kernel/trace/tracing_map.c
@@ -454,7 +454,7 @@ static struct tracing_map_elt *get_free_elt(struct tracing_map *map)
 	struct tracing_map_elt *elt = NULL;
 	int idx;
 
-	idx = atomic_inc_return(&map->next_elt);
+	idx = atomic_fetch_add_unless(&map->next_elt, 1, map->max_elts);
 	if (idx < map->max_elts) {
 		elt = *(TRACING_MAP_ELT(map->elts, idx));
 		if (map->ops && map->ops->elt_init)
@@ -699,7 +699,7 @@ void tracing_map_clear(struct tracing_map *map)
 {
 	unsigned int i;
 
-	atomic_set(&map->next_elt, -1);
+	atomic_set(&map->next_elt, 0);
 	atomic64_set(&map->hits, 0);
 	atomic64_set(&map->drops, 0);
 
@@ -783,7 +783,7 @@ struct tracing_map *tracing_map_create(unsigned int map_bits,
 
 	map->map_bits = map_bits;
 	map->max_elts = (1 << map_bits);
-	atomic_set(&map->next_elt, -1);
+	atomic_set(&map->next_elt, 0);
 
 	map->map_size = (1 << (map_bits + 1));
 	map->ops = ops;