From 27206bb57c47bdbe33bccc78fa7f7e2a719a06b9 Mon Sep 17 00:00:00 2001 From: Sumanth Korikkar Date: Mon, 6 Jul 2026 12:46:31 +0200 Subject: [PATCH] s390/perf_cpum_cf: Add missing array_index_nospec() to __hw_perf_event_init() commit 49145bce539117db4b6e9e83c0e5ef528e361050 upstream. ev variable is userspace controlled via event->attr.config and used as an array index after bounds checking, but without speculation barriers. Add the missing array_index_nospec() call to prevent speculative execution. Cc: stable@vger.kernel.org Fixes: 212188a596d1 ("[S390] perf: add support for s390x CPU counters") Signed-off-by: Sumanth Korikkar Reviewed-by: Ilya Leoshkevich Acked-by: Thomas Richter Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman --- arch/s390/kernel/perf_cpum_cf.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c index e590b4c09625..fbf4eb85cb0a 100644 --- a/arch/s390/kernel/perf_cpum_cf.c +++ b/arch/s390/kernel/perf_cpum_cf.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -766,6 +767,7 @@ static int __hw_perf_event_init(struct perf_event *event, unsigned int type) if (!is_userspace_event(ev)) { if (ev >= ARRAY_SIZE(cpumf_generic_events_user)) return -EOPNOTSUPP; + ev = array_index_nospec(ev, ARRAY_SIZE(cpumf_generic_events_user)); ev = cpumf_generic_events_user[ev]; } } else if (!attr->exclude_kernel && attr->exclude_user) { @@ -776,6 +778,7 @@ static int __hw_perf_event_init(struct perf_event *event, unsigned int type) if (!is_userspace_event(ev)) { if (ev >= ARRAY_SIZE(cpumf_generic_events_basic)) return -EOPNOTSUPP; + ev = array_index_nospec(ev, ARRAY_SIZE(cpumf_generic_events_basic)); ev = cpumf_generic_events_basic[ev]; } }