Re: [BUG] perf tools: off-by-one error in map_groups__find_ams()

[Stephane Eranian]

On Fri, Oct 3, 2014 at 10:09 AM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> On Thu, Oct 02, 2014 at 06:40:14PM +0200, Stephane Eranian wrote:
>> On Thu, Oct 2, 2014 at 10:36 AM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>> > On Wed, Oct 01, 2014 at 09:16:31PM +0200, Stephane Eranian wrote:
>> >> Hi,
>> >>
>> >> It appears that there is a off-by-one bug in map_groups__find_ams().
>> >> The upper-bound check in the test below should be >= because
>> >> end = start + len; The end address is outside the range.
>> >>
>> >> Please confirm.
>> >>
>> >>
>> >> int map_groups__find_ams(struct addr_map_symbol *ams, symbol_filter_t filter)
>> >> {
>> >>                 if (ams->addr < ams->map->start || ams->addr > ams->map->end) {
>> >
>> > yep, looks like bug to me
>> >
>> Are you providing a fix or should I?
>
> please go ahead
>
Based on the same reasoning, I am wondering about the following too:

util/map.c:
int map_groups__fixup_overlappings()
{

          after->start = map->end + 1;
                                                  ^^^ should not be there
}
The first byte after a map is at map->end. Range if [start;end[
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