From: Igor Lubashev <[email protected]> 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 <[email protected]> Signed-off-by: Igor Lubashev <[email protected]> Tested-by: Mathieu Poirier <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Alexey Budankov <[email protected]> Cc: James Morris <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Suzuki Poulouse <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Dahl <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- 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 @@ -682,11 +682,13 @@ int perf_event__synthesize_kernel_mmap(s 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 @@ -710,7 +712,6 @@ int perf_event__synthesize_kernel_mmap(s event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL; } - kmap = map__kmap(map); size = snprintf(event->mmap.filename, sizeof(event->mmap.filename), "%s%s", mmap_name, kmap->ref_reloc_sym->name) + 1; size = PERF_ALIGN(size, sizeof(u64));

