| Message ID | 20190604042953.914-1-ravi.bangoria@linux.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] perf ioctl: Add check for the sample_period value | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch next (a3bf9fbdad600b1e4335dd90979f8d6072e4f602) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 9 lines checked |
Peter / mpe, Is the v2 looks good? If so, can anyone of you please pick this up. On 6/4/19 9:59 AM, Ravi Bangoria wrote: > perf_event_open() limits the sample_period to 63 bits. See > commit 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period > to 63 bits"). Make ioctl() consistent with it. > > Also on powerpc, negative sample_period could cause a recursive > PMIs leading to a hang (reported when running perf-fuzzer). > > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> > --- > kernel/events/core.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/kernel/events/core.c b/kernel/events/core.c > index abbd4b3b96c2..e44c90378940 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -5005,6 +5005,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) > if (perf_event_check_period(event, value)) > return -EINVAL; > > + if (!event->attr.freq && (value & (1ULL << 63))) > + return -EINVAL; > + > event_function_call(event, __perf_event_period, &value); > > return 0; >
Ravi Bangoria <ravi.bangoria@linux.ibm.com> writes: > Peter / mpe, > > Is the v2 looks good? If so, can anyone of you please pick this up. I usually wouldn't take it, it's generic perf code. Unless peter/ingo/acme tell me otherwise. It's sort of a bug fix for 0819b2e30ccb, should it have a fixes and/or stable tag? Fixes: 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits") Cc: stable@vger.kernel.org # v3.15+ cheers > On 6/4/19 9:59 AM, Ravi Bangoria wrote: >> perf_event_open() limits the sample_period to 63 bits. See >> commit 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period >> to 63 bits"). Make ioctl() consistent with it. >> >> Also on powerpc, negative sample_period could cause a recursive >> PMIs leading to a hang (reported when running perf-fuzzer). >> >> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> >> --- >> kernel/events/core.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/kernel/events/core.c b/kernel/events/core.c >> index abbd4b3b96c2..e44c90378940 100644 >> --- a/kernel/events/core.c >> +++ b/kernel/events/core.c >> @@ -5005,6 +5005,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) >> if (perf_event_check_period(event, value)) >> return -EINVAL; >> >> + if (!event->attr.freq && (value & (1ULL << 63))) >> + return -EINVAL; >> + >> event_function_call(event, __perf_event_period, &value); >> >> return 0; >>
diff --git a/kernel/events/core.c b/kernel/events/core.c index abbd4b3b96c2..e44c90378940 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5005,6 +5005,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) if (perf_event_check_period(event, value)) return -EINVAL; + if (!event->attr.freq && (value & (1ULL << 63))) + return -EINVAL; + event_function_call(event, __perf_event_period, &value); return 0;
perf_event_open() limits the sample_period to 63 bits. See commit 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits"). Make ioctl() consistent with it. Also on powerpc, negative sample_period could cause a recursive PMIs leading to a hang (reported when running perf-fuzzer). Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> --- kernel/events/core.c | 3 +++ 1 file changed, 3 insertions(+)