Commit 198376cd authored Jun 03, 2014 by Yoshihiro YUNOMAE Committed by Steven Rostedt Jun 03, 2014

tracing: Eliminate double free on failure of allocation on boot up

If allocation of the max_buffer fails on boot up, the error path will
free both per_cpu data structures from the buffers. With the new redesign
of the code, those structures are freed if allocations failed. That is,
the helper function that allocates the buffers will free the per cpu data
on failure. No need to do it again. In fact, the second free will cause
a bug as the code can not handle a double free.

Link: http://lkml.kernel.org/p/20140603042803.27308.30956.stgit@yunodevel

Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

parent 964f7b6b

kernel/trace/trace.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -6671,10 +6671,6 @@ __init static int tracer_alloc_buffers(void)
		out_free_temp_buffer:
		ring_buffer_free(temp_buffer);
		out_free_cpumask:
		free_percpu(global_trace.trace_buffer.data);
		#ifdef CONFIG_TRACER_MAX_TRACE
		free_percpu(global_trace.max_buffer.data);
		#endif
		free_cpumask_var(global_trace.tracing_cpumask);
		out_free_buffer_mask:
		free_cpumask_var(tracing_buffer_mask);

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