From: Xiaomeng Tong xiam0nd.tong@gmail.com
commit 2012a9e279013933885983cbe0a5fe828052563b upstream.
The bug is here: return cluster;
The list iterator value 'cluster' will *always* be set and non-NULL by list_for_each_entry(), so it is incorrect to assume that the iterator value will be NULL if the list is empty or no element is found.
To fix the bug, return 'cluster' when found, otherwise return NULL.
Cc: stable@vger.kernel.org Fixes: 21bdbb7102ed ("perf: add qcom l2 cache perf events driver") Signed-off-by: Xiaomeng Tong xiam0nd.tong@gmail.com Link: https://lore.kernel.org/r/20220327055733.4070-1-xiam0nd.tong@gmail.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/perf/qcom_l2_pmu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/perf/qcom_l2_pmu.c +++ b/drivers/perf/qcom_l2_pmu.c @@ -744,7 +744,7 @@ static struct cluster_pmu *l2_cache_asso { u64 mpidr; int cpu_cluster_id; - struct cluster_pmu *cluster = NULL; + struct cluster_pmu *cluster;
/* * This assumes that the cluster_id is in MPIDR[aff1] for @@ -766,10 +766,10 @@ static struct cluster_pmu *l2_cache_asso cluster->cluster_id); cpumask_set_cpu(cpu, &cluster->cluster_cpus); *per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu) = cluster; - break; + return cluster; }
- return cluster; + return NULL; }
static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)