[PATCH] perf: hisi: Fix use-after-free when register pmu fails

[Junhao He]

When we fail to register the uncore pmu, the pmu context may not been
allocated. The error handing will call cpuhp_state_remove_instance()
to call uncore pmu offline callback, which migrate the pmu context.
Since that's liable to lead to some kind of use-after-free.

Use cpuhp_state_remove_instance_nocalls() instead of
cpuhp_state_remove_instance() so that the notifiers don't execute after
the PMU device has been failed to register.

Fixes: a0ab25cd82ee ("drivers/perf: hisi: Add support for HiSilicon PA PMU driver")
FIxes: 3bf30882c3c7 ("drivers/perf: hisi: Add support for HiSilicon SLLC PMU driver")
Signed-off-by: Junhao He <hejunhao3 at huawei.com>
---
 drivers/perf/hisilicon/hisi_uncore_pa_pmu.c   | 4 ++--
 drivers/perf/hisilicon/hisi_uncore_sllc_pmu.c | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/perf/hisilicon/hisi_uncore_pa_pmu.c b/drivers/perf/hisilicon/hisi_uncore_pa_pmu.c
index d941e746b424..797cf201996a 100644
--- a/drivers/perf/hisilicon/hisi_uncore_pa_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_pa_pmu.c
@@ -505,8 +505,8 @@ static int hisi_pa_pmu_probe(struct platform_device *pdev)
 	ret = perf_pmu_register(&pa_pmu->pmu, name, -1);
 	if (ret) {
 		dev_err(pa_pmu->dev, "PMU register failed, ret = %d\n", ret);
-		cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_HISI_PA_ONLINE,
-					    &pa_pmu->node);
+		cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_HISI_PA_ONLINE,
+						    &pa_pmu->node);
 		return ret;
 	}
 
diff --git a/drivers/perf/hisilicon/hisi_uncore_sllc_pmu.c b/drivers/perf/hisilicon/hisi_uncore_sllc_pmu.c
index 6fe534a665ed..e706ca567676 100644
--- a/drivers/perf/hisilicon/hisi_uncore_sllc_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_sllc_pmu.c
@@ -450,8 +450,8 @@ static int hisi_sllc_pmu_probe(struct platform_device *pdev)
 	ret = perf_pmu_register(&sllc_pmu->pmu, name, -1);
 	if (ret) {
 		dev_err(sllc_pmu->dev, "PMU register failed, ret = %d\n", ret);
-		cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE,
-					    &sllc_pmu->node);
+		cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE,
+						    &sllc_pmu->node);
 		return ret;
 	}
 
-- 
2.33.0