tracing: Return error if ftrace_trace_arrays list is empty
ftrace_trace_arrays links global_trace.list. However, global_trace is not added to ftrace_trace_arrays if trace_alloc_buffers() failed. As the result, ftrace_trace_arrays becomes an empty list. If ftrace_trace_arrays is an empty list, current top_trace_array() returns an invalid pointer. As the result, the kernel can induce memory corruption or panic. Current implementation does not check whether ftrace_trace_arrays is empty list or not. So, in this patch, if ftrace_trace_arrays is empty list, top_trace_array() returns NULL. Moreover, this patch makes all functions calling top_trace_array() handle it appropriately. Link: http://lkml.kernel.org/p/20140605223517.32311.99233.stgit@yunodevel Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Родитель
34839f5a69
Коммит
dc81e5e3ab
|
@ -252,6 +252,9 @@ static inline struct trace_array *top_trace_array(void)
|
|||
{
|
||||
struct trace_array *tr;
|
||||
|
||||
if (list_empty(ftrace_trace_arrays.prev))
|
||||
return NULL;
|
||||
|
||||
tr = list_entry(ftrace_trace_arrays.prev,
|
||||
typeof(*tr), list);
|
||||
WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
|
||||
|
|
|
@ -574,6 +574,9 @@ int trace_set_clr_event(const char *system, const char *event, int set)
|
|||
{
|
||||
struct trace_array *tr = top_trace_array();
|
||||
|
||||
if (!tr)
|
||||
return -ENODEV;
|
||||
|
||||
return __ftrace_set_clr_event(tr, NULL, system, event, set);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(trace_set_clr_event);
|
||||
|
@ -2065,6 +2068,9 @@ event_enable_func(struct ftrace_hash *hash,
|
|||
bool enable;
|
||||
int ret;
|
||||
|
||||
if (!tr)
|
||||
return -ENODEV;
|
||||
|
||||
/* hash funcs only work with set_ftrace_filter */
|
||||
if (!enabled || !param)
|
||||
return -EINVAL;
|
||||
|
@ -2396,6 +2402,9 @@ static __init int event_trace_enable(void)
|
|||
char *token;
|
||||
int ret;
|
||||
|
||||
if (!tr)
|
||||
return -ENODEV;
|
||||
|
||||
for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
|
||||
|
||||
call = *iter;
|
||||
|
@ -2442,6 +2451,8 @@ static __init int event_trace_init(void)
|
|||
int ret;
|
||||
|
||||
tr = top_trace_array();
|
||||
if (!tr)
|
||||
return -ENODEV;
|
||||
|
||||
d_tracer = tracing_init_dentry();
|
||||
if (!d_tracer)
|
||||
|
@ -2535,6 +2546,8 @@ static __init void event_trace_self_tests(void)
|
|||
int ret;
|
||||
|
||||
tr = top_trace_array();
|
||||
if (!tr)
|
||||
return;
|
||||
|
||||
pr_info("Running tests on trace events:\n");
|
||||
|
||||
|
|
Загрузка…
Ссылка в новой задаче