Commit ee5061f8 authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
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perf symbol-elf: Ensure dso__put() in machine__process_ksymbol_register() 



The dso__put() after the map creation causes a use after put in
dso__set_loaded().

To ensure there is a +1 reference count on both sides of the if-else, do
a dso__get() on the found map's dso.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/r/20240506180104.485674-3-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 7fdc33f8

tools/perf/util/machine.c

+3 −3
Original line number Diff line number Diff line
@@ -683,7 +683,7 @@ static int machine__process_ksymbol_register(struct machine *machine, 
					     struct perf_sample *sample __maybe_unused)

{

	struct symbol *sym;

	struct dso *dso;

	struct dso *dso = NULL;

	struct map *map = maps__find(machine__kernel_maps(machine), event->ksymbol.addr);

	int err = 0;
@@ -696,7 +696,6 @@ static int machine__process_ksymbol_register(struct machine *machine, 
		}

		dso__set_kernel(dso, DSO_SPACE__KERNEL);

		map = map__new2(0, dso);

		dso__put(dso);

		if (!map) {

			err = -ENOMEM;

			goto out;
@@ -722,7 +721,7 @@ static int machine__process_ksymbol_register(struct machine *machine, 
			dso__set_long_name(dso, "", false);

		}

	} else {

		dso = map__dso(map);

		dso = dso__get(map__dso(map));

	}



	sym = symbol__new(map__map_ip(map, map__start(map)),
@@ -735,6 +734,7 @@ static int machine__process_ksymbol_register(struct machine *machine, 
	dso__insert_symbol(dso, sym);

out:

	map__put(map);

	dso__put(dso);

	return err;

}