From: Igor Lubashev <ilubashe@xxxxxxxxxx> commit e9a6882f267a8105461066e3ea6b4b6b9be1b807 upstream. Check for ref_reloc_sym before using it instead of checking symbol_conf.kptr_restrict and relying solely on that check. Reported-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Signed-off-by: Igor Lubashev <ilubashe@xxxxxxxxxx> Tested-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx> Cc: James Morris <jmorris@xxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Suzuki Poulouse <suzuki.poulose@xxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/1566869956-7154-2-git-send-email-ilubashe@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Alexander Dahl <ada@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/util/event.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/tools/perf/util/event.c +++ b/tools/perf/util/event.c @@ -912,11 +912,13 @@ static int __perf_event__synthesize_kern int err; union perf_event *event; - if (symbol_conf.kptr_restrict) - return -1; if (map == NULL) return -1; + kmap = map__kmap(map); + if (!kmap->ref_reloc_sym) + return -1; + /* * We should get this from /sys/kernel/sections/.text, but till that is * available use this, and after it is use this as a fallback for older @@ -939,7 +941,6 @@ static int __perf_event__synthesize_kern event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL; } - kmap = map__kmap(map); size = snprintf(event->mmap.filename, sizeof(event->mmap.filename), "%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1; size = PERF_ALIGN(size, sizeof(u64));
