perf tools: fix off-by-one error in maps

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 <eranian@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20141006083532.GA4850@quad
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index b7090596ac50..186418ba18db 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -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,
@@ -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);
@@ -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);