tracing/filters: Always free pred on filter_add_subsystem_pred() failure

If filter_add_subsystem_pred() fails due to ENOSPC or ENOMEM,
the pred doesn't get freed, while as a side effect it does for
other errors. Make it so the caller always frees the pred for
any error.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1249746593.6453.32.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 5 deletions

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 1557148be34b..f32dc9d1ea7b 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -624,9 +624,6 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
                 return -ENOSPC;
         }
 
-        filter->preds[filter->n_preds] = pred;
-        filter->n_preds++;
-
         list_for_each_entry(call, &ftrace_events, list) {
 
                 if (!call->define_fields)
@@ -643,6 +640,9 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
                 }
                 replace_filter_string(call->filter, filter_string);
         }
+
+        filter->preds[filter->n_preds] = pred;
+        filter->n_preds++;
 out:
         return err;
 }
@@ -1034,9 +1034,12 @@ static int replace_preds(struct event_subsystem *system,
                         if (call) {
                                 err = filter_add_pred(ps, call, pred);
                                 filter_free_pred(pred);
-                        } else
+                        } else {
                                 err = filter_add_subsystem_pred(ps, system,
                                                         pred, filter_string);
+                                if (err)
+                                        filter_free_pred(pred);
+                        }
                         if (err)
                                 return err;
 
@@ -1055,9 +1058,12 @@ static int replace_preds(struct event_subsystem *system,
                 if (call) {
                         err = filter_add_pred(ps, call, pred);
                         filter_free_pred(pred);
-                } else
+                } else {
                         err = filter_add_subsystem_pred(ps, system, pred,
                                                         filter_string);
+                        if (err)
+                                filter_free_pred(pred);
+                }
                 if (err)
                         return err;