perf segfault in in ordered_events__free()
From: Song Liu
Date: Wed Jan 16 2019 - 13:58:04 EST
Hi,
We are debugging a segfault of perf in ordered_events__free().
Disassemble shows the segfault was caused by oe->buff == NULL
in the following line:
/*
* Current buffer might not have all the events allocated
* yet, we need to free only allocated ones ...
*/
list_del(&oe->buffer->list);
After poking around the code, I suspect it is caused by the following
condition in alloc_event():
} else if (oe->buffer) {
new = &oe->buffer->event[oe->buffer_idx];
if (++oe->buffer_idx == MAX_SAMPLE_BUFFER)
oe->buffer = NULL;
Does this theory make sense? If so, what would be the best fix?
Thanks in advance!
Song