ACPI: processor: Fix memory leaks in error paths of processor_add()

[ Upstream commit 47ec9b417ed9b6b8ec2a941cd84d9de62adc358a ]

If acpi_processor_get_info() returned an error, pr and the associated
pr->throttling.shared_cpu_map were leaked.

The unwind code was in the wrong order wrt to setup, relying on
some unwind actions having no affect (clearing variables that were
never set etc).  That makes it harder to reason about so reorder
and add appropriate labels to only undo what was actually set up
in the first place.

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240529133446.28446-6-Jonathan.Cameron@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 9702c1bc5f8081585d236fa16a644b61161a036a..707b2c37e5ee6e286794a133371e0895f75cfee9 100644 (file)
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -387,7 +387,7 @@ static int acpi_processor_add(struct acpi_device *device,
 
        result = acpi_processor_get_info(device);
        if (result) /* Processor is not physically present or unavailable */
-               return result;
+               goto err_clear_driver_data;
 
        BUG_ON(pr->id >= nr_cpu_ids);
 
@@ -402,7 +402,7 @@ static int acpi_processor_add(struct acpi_device *device,
                        "BIOS reported wrong ACPI id %d for the processor\n",
                        pr->id);
                /* Give up, but do not abort the namespace scan. */
-               goto err;
+               goto err_clear_driver_data;
        }
        /*
         * processor_device_array is not cleared on errors to allow buggy BIOS
@@ -414,12 +414,12 @@ static int acpi_processor_add(struct acpi_device *device,
        dev = get_cpu_device(pr->id);
        if (!dev) {
                result = -ENODEV;
-               goto err;
+               goto err_clear_per_cpu;
        }
 
        result = acpi_bind_one(dev, device);
        if (result)
-               goto err;
+               goto err_clear_per_cpu;
 
        pr->dev = dev;
 
@@ -430,10 +430,11 @@ static int acpi_processor_add(struct acpi_device *device,
        dev_err(dev, "Processor driver could not be attached\n");
        acpi_unbind_one(dev);
 
- err:
-       free_cpumask_var(pr->throttling.shared_cpu_map);
-       device->driver_data = NULL;
+ err_clear_per_cpu:
        per_cpu(processors, pr->id) = NULL;
+ err_clear_driver_data:
+       device->driver_data = NULL;
+       free_cpumask_var(pr->throttling.shared_cpu_map);
  err_free_pr:
        kfree(pr);
        return result;