Finding a map is done under a lock, returning the map without a
reference count means it can be removed without notice and causing
uses after free. Grab a reference count to the map within the lock
region and return this. Fix up locations that need a map__put
following this.
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/machine.c | 4 +++-
tools/perf/util/maps.c | 2 +-
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 7031f6fddcae..4911734411b5 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1761,8 +1761,10 @@ int machine__create_kernel_maps(struct machine *machine)
struct map *next = maps__find_next_entry(machine__kernel_maps(machine),
machine__kernel_map(machine));
- if (next)
+ if (next) {
machine__set_kernel_mmap(machine, start, map__start(next));
+ map__put(next);
+ }
}
out_put:
diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c
index f4855e2bfd6e..e577909456be 100644
--- a/tools/perf/util/maps.c
+++ b/tools/perf/util/maps.c
@@ -956,7 +956,7 @@ struct map *maps__find_next_entry(struct maps *maps, struct map *map)
down_read(maps__lock(maps));
i = maps__by_address_index(maps, map);
if (i < maps__nr_maps(maps))
- result = maps__maps_by_address(maps)[i]; // TODO: map__get
+ result = map__get(maps__maps_by_address(maps)[i]);
up_read(maps__lock(maps));
return result;
--
2.43.0.594.gd9cf4e227d-goog
