Merge tag 'trace-v5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Three tracing fixes:

   - Make local osnoise_instances static

   - Copy just actual size of histogram strings

   - Properly check missing operands in histogram expressions"

* tag 'trace-v5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/histogram: Fix check for missing operands in an expression
  tracing/histogram: Do not copy the fixed-size char array field over the field size
  tracing/osnoise: Make osnoise_instances static

Author: torvalds

kernel/trace/trace_events_hist.c

@@ -1953,9 +1953,10 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 		if (!hist_field->type)
 			goto free;
 
-		if (field->filter_type == FILTER_STATIC_STRING)
+		if (field->filter_type == FILTER_STATIC_STRING) {
 			hist_field->fn = hist_field_string;
-		else if (field->filter_type == FILTER_DYN_STRING)
+			hist_field->size = field->size;
+		} else if (field->filter_type == FILTER_DYN_STRING)
 			hist_field->fn = hist_field_dynstring;
 		else
 			hist_field->fn = hist_field_pstring;
@@ -2580,7 +2581,8 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
 	operand1_str = str;
 	str = sep+1;
 
-	if (!operand1_str || !str)
+	/* Binary operator requires both operands */
+	if (*operand1_str == '\0' || *str == '\0')
 		goto free;
 
 	operand_flags = 0;
@@ -3025,7 +3027,7 @@ static inline void __update_field_vars(struct tracing_map_elt *elt,
 			char *str = elt_data->field_var_str[j++];
 			char *val_str = (char *)(uintptr_t)var_val;
 
-			strscpy(str, val_str, STR_VAR_LEN_MAX);
+			strscpy(str, val_str, val->size);
 			var_val = (u64)(uintptr_t)str;
 		}
 		tracing_map_set_var(elt, var_idx, var_val);
@@ -4920,7 +4922,7 @@ static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
 
 				str = elt_data->field_var_str[idx];
 				val_str = (char *)(uintptr_t)hist_val;
-				strscpy(str, val_str, STR_VAR_LEN_MAX);
+				strscpy(str, val_str, hist_field->size);
 
 				hist_val = (u64)(uintptr_t)str;
 			}

kernel/trace/trace_osnoise.c

@@ -55,7 +55,8 @@ struct osnoise_instance {
 	struct list_head	list;
 	struct trace_array	*tr;
 };
-struct list_head osnoise_instances;
+
+static struct list_head osnoise_instances;
 
 static bool osnoise_has_registered_instances(void)
 {