From: Peter Zijlstra peterz@infradead.org
[ Upstream commit 1e69a0efc0bd0e02b8327e7186fbb4a81878ea0b ]
UBSAN reported out-of-bound accesses for x86_pmu.event_map(), it's arguments should be < x86_pmu.max_events. Make sure all users observe this constraint.
Reported-by: Meelis Roos mroos@linux.ee Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Tested-by: Meelis Roos mroos@linux.ee Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/events/core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 7b21455d7504..b9673396b571 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1641,9 +1641,12 @@ static struct attribute_group x86_pmu_format_group __ro_after_init = {
ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, char *page) { - struct perf_pmu_events_attr *pmu_attr = \ + struct perf_pmu_events_attr *pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); - u64 config = x86_pmu.event_map(pmu_attr->id); + u64 config = 0; + + if (pmu_attr->id < x86_pmu.max_events) + config = x86_pmu.event_map(pmu_attr->id);
/* string trumps id */ if (pmu_attr->event_str) @@ -1712,6 +1715,9 @@ is_visible(struct kobject *kobj, struct attribute *attr, int idx) { struct perf_pmu_events_attr *pmu_attr;
+ if (idx >= x86_pmu.max_events) + return 0; + pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr); /* str trumps id */ return pmu_attr->event_str || x86_pmu.event_map(idx) ? attr->mode : 0;