From: Xiaomeng Tong xiam0nd.tong@gmail.com
stable inclusion from stable-v5.10.111 commit 451214b266e949b219d27faa9f44b434086a2f92 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5GL1Z
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
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 Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- drivers/perf/qcom_l2_pmu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/perf/qcom_l2_pmu.c b/drivers/perf/qcom_l2_pmu.c index 23a0e008dafa..d58810f53727 100644 --- a/drivers/perf/qcom_l2_pmu.c +++ b/drivers/perf/qcom_l2_pmu.c @@ -739,7 +739,7 @@ static struct cluster_pmu *l2_cache_associate_cpu_with_cluster( { 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 @@ -761,10 +761,10 @@ static struct cluster_pmu *l2_cache_associate_cpu_with_cluster( 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)