diff options
| author | Hendrik Brueckner <brueckner@linux.ibm.com> | 2018-05-03 15:56:15 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-26 08:48:55 +0200 |
| commit | 55b21399d8d94ec124cc5ceed2e11f9be53d9e13 (patch) | |
| tree | 3a92143e2a360109416157601ee81c3430655d50 | |
| parent | 9c32e0d3655efc6f5b556614a6713870da477d05 (diff) | |
s390/cpum_sf: ensure sample frequency of perf event attributes is non-zero
commit 4bbaf2584b86b0772413edeac22ff448f36351b1 upstream.
Correct a trinity finding for the perf_event_open() system call with
a perf event attribute structure that uses a frequency but has the
sampling frequency set to zero. This causes a FP divide exception during
the sample rate initialization for the hardware sampling facility.
Fixes: 8c069ff4bd606 ("s390/perf: add support for the CPU-Measurement Sampling Facility")
Cc: stable@vger.kernel.org # 3.14+
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/s390/kernel/perf_cpum_sf.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index 3d8da1e742c2..b79d51459cf2 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -744,6 +744,10 @@ static int __hw_perf_event_init(struct perf_event *event) */ rate = 0; if (attr->freq) { + if (!attr->sample_freq) { + err = -EINVAL; + goto out; + } rate = freq_to_sample_rate(&si, attr->sample_freq); rate = hw_limit_rate(&si, rate); attr->freq = 0; |