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perf tools: fix off-by-one error in maps
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This patch fixes off-by-one errors in the management of maps.

A map is defined by start address and length as implemented by
map__new():

  map__init(map, type, start, start + len, pgoff, dso);

  map->start = addr;
  map->end = end;

Consequently, the actual address range is [start; end[ map->end is the
first byte outside the range.

This patch fixes two bugs where upper bound checking was off-by-one.

In V2, we fix map_groups__fixup_overlappings() some more where
map->start was off-by-one as reported by Jiri.

Signed-off-by: Stephane Eranian <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/20141006083532.GA4850@quad
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Stephane Eranian authored and acmel committed Oct 14, 2014
1 parent e167f99 commit 77faf4d
Showing 1 changed file with 3 additions and 3 deletions.
6 changes: 3 additions & 3 deletions tools/perf/util/map.c
Original file line number Diff line number Diff line change
Expand Up @@ -556,7 +556,7 @@ struct symbol *map_groups__find_symbol_by_name(struct map_groups *mg,

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) {
if (ams->addr < ams->map->start || ams->addr >= ams->map->end) {
if (ams->map->groups == NULL)
return -1;
ams->map = map_groups__find(ams->map->groups, ams->map->type,
Expand Down Expand Up @@ -664,7 +664,7 @@ int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map,
goto move_map;
}

before->end = map->start - 1;
before->end = map->start;
map_groups__insert(mg, before);
if (verbose >= 2)
map__fprintf(before, fp);
Expand All @@ -678,7 +678,7 @@ int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map,
goto move_map;
}

after->start = map->end + 1;
after->start = map->end;
map_groups__insert(mg, after);
if (verbose >= 2)
map__fprintf(after, fp);
Expand Down

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