Merge tag 'trace-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Do not allow histogram values to have modifies. They can cause a NULL
   pointer dereference if they do.

 - Warn if hist_field_name() is passed a NULL. Prevent the NULL pointer
   dereference mentioned above.

 - Fix invalid address look up race in lookup_rec()

 - Define ftrace_stub_graph conditionally to prevent linker errors

 - Always check if RCU is watching at all tracepoint locations

* tag 'trace-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Make tracepoint lockdep check actually test something
  ftrace,kcfi: Define ftrace_stub_graph conditionally
  ftrace: Fix invalid address access in lookup_rec() when index is 0
  tracing: Check field value in hist_field_name()
  tracing: Do not let histogram values have some modifiers

2 files changed, 14 insertions, 1 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 29baa97d0d53..9b2803c7a18f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1564,7 +1564,8 @@ static struct dyn_ftrace *lookup_rec(unsigned long start, unsigned long end)
 	key.flags = end;	/* overload flags, as it is unsigned long */
 
 	for (pg = ftrace_pages_start; pg; pg = pg->next) {
-		if (end < pg->records[0].ip ||
+		if (pg->index == 0 ||
+		    end < pg->records[0].ip ||
 		    start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
 			continue;
 		rec = bsearch(&key, pg->records, pg->index,
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 89877a18f933..486cca3c2b75 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1331,6 +1331,9 @@ static const char *hist_field_name(struct hist_field *field,
 {
 	const char *field_name = "";
 
+	if (WARN_ON_ONCE(!field))
+		return field_name;
+
 	if (level > 1)
 		return field_name;
 
@@ -4235,6 +4238,15 @@ static int __create_val_field(struct hist_trigger_data *hist_data,
 		goto out;
 	}
 
+	/* Some types cannot be a value */
+	if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT |
+				 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 |
+				 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET |
+				 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE)) {
+		hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str));
+		ret = -EINVAL;
+	}
+
 	hist_data->fields[val_idx] = hist_field;
 
 	++hist_data->n_vals;