Commit 77faf4d0 authored Oct 06, 2014 by Stephane Eranian Committed by Arnaldo Carvalho de Melo Oct 14, 2014

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>

parent e167f995

tools/perf/util/map.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -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);

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