Messages in this thread Patch in this message | | | From | Alexander Z Lam <> | Subject | [PATCH 3/3] tracing: Protect ftrace_trace_arrays list in trace_events.c | Date | Mon, 1 Jul 2013 15:31:25 -0700 |
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There are multiple places where the ftrace_trace_arrays list is accessed in trace_events.c without the trace_types_lock held.
Cc: David Sharp <dhsharp@google.com> Cc: Alexander Z Lam <lambchop468@gmail.com> Signed-off-by: Alexander Z Lam <azl@google.com> --- kernel/trace/trace_events.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 6db3290..26351cc 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1586,6 +1586,7 @@ static void __add_event_to_tracers(struct ftrace_event_call *call, int trace_add_event_call(struct ftrace_event_call *call) { int ret; + mutex_lock(&trace_types_lock); mutex_lock(&event_mutex); ret = __register_event(call, NULL); @@ -1593,11 +1594,13 @@ int trace_add_event_call(struct ftrace_event_call *call) __add_event_to_tracers(call, NULL); mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); return ret; } /* - * Must be called under locking both of event_mutex and trace_event_sem. + * Must be called under locking of trace_types_lock, event_mutex and + * trace_event_sem. */ static void __trace_remove_event_call(struct ftrace_event_call *call) { @@ -1609,11 +1612,13 @@ static void __trace_remove_event_call(struct ftrace_event_call *call) /* Remove an event_call */ void trace_remove_event_call(struct ftrace_event_call *call) { + mutex_lock(&trace_types_lock); mutex_lock(&event_mutex); down_write(&trace_event_sem); __trace_remove_event_call(call); up_write(&trace_event_sem); mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); } #define for_each_event(event, start, end) \ @@ -1757,6 +1762,7 @@ static int trace_module_notify(struct notifier_block *self, { struct module *mod = data; + mutex_lock(&trace_types_lock); mutex_lock(&event_mutex); switch (val) { case MODULE_STATE_COMING: @@ -1767,6 +1773,7 @@ static int trace_module_notify(struct notifier_block *self, break; } mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); return 0; } -- 1.8.3
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