diff options
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace.h | 23 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 33 | ||||
| -rw-r--r-- | kernel/trace/trace_events_hist.c | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_events_inject.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_events_trigger.c | 6 | ||||
| -rw-r--r-- | kernel/trace/tracing_map.c | 6 |
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; |