From c69a2324fc6b0bbac8d98fab667176e187d8e3fd Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Wed, 12 Oct 2022 11:22:58 +0300 Subject: [PATCH] perf intel-pt: Fix segfault in intel_pt_print_info() with uClibc commit 5a3d47071f0ced0431ef82a5fb6bd077ed9493db upstream. uClibc segfaulted because NULL was passed as the format to fprintf(). That happened because one of the format strings was missing and intel_pt_print_info() didn't check that before calling fprintf(). Add the missing format string, and check format is not NULL before calling fprintf(). Fixes: 11fa7cb86b56d361 ("perf tools: Pass Intel PT information for decoding MTC and CYC") Signed-off-by: Adrian Hunter Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20221012082259.22394-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/intel-pt.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c index c3ceac1..6324195 100644 --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -3591,6 +3591,7 @@ static const char * const intel_pt_info_fmts[] = { [INTEL_PT_SNAPSHOT_MODE] = " Snapshot mode %"PRId64"\n", [INTEL_PT_PER_CPU_MMAPS] = " Per-cpu maps %"PRId64"\n", [INTEL_PT_MTC_BIT] = " MTC bit %#"PRIx64"\n", + [INTEL_PT_MTC_FREQ_BITS] = " MTC freq bits %#"PRIx64"\n", [INTEL_PT_TSC_CTC_N] = " TSC:CTC numerator %"PRIu64"\n", [INTEL_PT_TSC_CTC_D] = " TSC:CTC denominator %"PRIu64"\n", [INTEL_PT_CYC_BIT] = " CYC bit %#"PRIx64"\n", @@ -3605,8 +3606,12 @@ static void intel_pt_print_info(__u64 *arr, int start, int finish) if (!dump_trace) return; - for (i = start; i <= finish; i++) - fprintf(stdout, intel_pt_info_fmts[i], arr[i]); + for (i = start; i <= finish; i++) { + const char *fmt = intel_pt_info_fmts[i]; + + if (fmt) + fprintf(stdout, fmt, arr[i]); + } } static void intel_pt_print_info_str(const char *name, const char *str) -- 2.7.4