From: Ravi Bangoria <ravi.bango...@linux.ibm.com> [ Upstream commit 913a90bc5a3a06b1f04c337320e9aeee2328dd77 ]
perf_event_open() limits the sample_period to 63 bits. See: 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.bango...@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> Cc: Arnaldo Carvalho de Melo <a...@redhat.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Stephane Eranian <eran...@google.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Vince Weaver <vincent.wea...@maine.edu> Cc: a...@kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: ma...@linux.vnet.ibm.com Cc: m...@ellerman.id.au Fixes: 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits") Link: https://lkml.kernel.org/r/20190604042953.914-1-ravi.bango...@linux.ibm.com Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Sasha Levin <sas...@kernel.org> --- kernel/events/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 5bbf7537a6121..64ace5e9af2a0 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4624,6 +4624,9 @@ 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; -- 2.20.1