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| author | Ingo Molnar <mingo@elte.hu> | 2009-10-15 12:24:04 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-10-15 12:41:56 +0200 |
| commit | a66abe7fbf7805a1a02f241bd5283265ff6706ec (patch) | |
| tree | 7b39b4339f8b5caf56c4f76c485f07b23861999b /kernel | |
| parent | perf trace: Add filter Suppport (diff) | |
| download | linux-a66abe7fbf7805a1a02f241bd5283265ff6706ec.tar.xz linux-a66abe7fbf7805a1a02f241bd5283265ff6706ec.zip | |
tracing/events: Fix locking imbalance in the filter code
Américo Wang noticed that we have a locking imbalance in the
error paths of ftrace_profile_set_filter(), causing potential
leakage of event_mutex.
Also clean up other error codepaths related to event_mutex
while at it.
Plus fix an initialized variable in the subsystem filter code.
Reported-by: Américo Wang <xiyou.wangcong@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <2375c9f90910150247u5ccb8e2at58c764e385ffa490@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_events_filter.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index e27bb6acc2dd..21d34757b955 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -1230,10 +1230,10 @@ static int replace_system_preds(struct event_subsystem *system, struct filter_parse_state *ps, char *filter_string) { + struct event_filter *filter = system->filter; struct ftrace_event_call *call; - struct event_filter *filter; - int err; bool fail = true; + int err; list_for_each_entry(call, &ftrace_events, list) { @@ -1262,7 +1262,7 @@ static int replace_system_preds(struct event_subsystem *system, if (fail) { parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); - return err; + return -EINVAL; } return 0; } @@ -1281,8 +1281,7 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string) if (!strcmp(strstrip(filter_string), "0")) { filter_disable_preds(call); remove_filter_string(call->filter); - mutex_unlock(&event_mutex); - return 0; + goto out_unlock; } err = -ENOMEM; @@ -1330,8 +1329,7 @@ int apply_subsystem_event_filter(struct event_subsystem *system, if (!strcmp(strstrip(filter_string), "0")) { filter_free_subsystem_preds(system); remove_filter_string(system->filter); - mutex_unlock(&event_mutex); - return 0; + goto out_unlock; } err = -ENOMEM; @@ -1386,15 +1384,20 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id, if (call->id == event_id) break; } + + err = -EINVAL; if (!call) - return -EINVAL; + goto out_unlock; + err = -EEXIST; if (event->filter) - return -EEXIST; + goto out_unlock; filter = __alloc_preds(); - if (IS_ERR(filter)) - return PTR_ERR(filter); + if (IS_ERR(filter)) { + err = PTR_ERR(filter); + goto out_unlock; + } err = -ENOMEM; ps = kzalloc(sizeof(*ps), GFP_KERNEL); @@ -1419,6 +1422,7 @@ free_preds: if (err) __free_preds(filter); +out_unlock: mutex_unlock(&event_mutex); return err; |