perf intel-pt: Fix segfault in intel_pt_print_info() with uClibc

commit 5a3d47071f 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: 11fa7cb86b ("perf tools: Pass Intel PT information for decoding MTC and CYC")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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 <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Adrian Hunter 2022-10-12 11:22:58 +03:00 committed by Greg Kroah-Hartman
parent e81bf40b28
commit c69a2324fc

View File

@ -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)