perf/x86/intel/uncore: Fix reference count leak in sad_cfg_iio_topolo…

…gy()

[ Upstream commit c508eb0 ]

pci_get_device() will increase the reference count for the returned
pci_dev, and also decrease the reference count for the input parameter
*from* if it is not NULL.

If we break the loop in sad_cfg_iio_topology() with 'dev' not NULL. We
need to call pci_dev_put() to decrease the reference count. Since
pci_dev_put() can handle the NULL input parameter, we can just add one
pci_dev_put() right before 'return ret'.

Fixes: c1777be ("perf/x86/intel/uncore: Enable I/O stacks to IIO PMON mapping on SNR")
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20221118063137.121512-2-wangxiongfeng2@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

arch/x86/events/intel/uncore_snbep.c

@@ -4492,6 +4492,8 @@ static int sad_cfg_iio_topology(struct intel_uncore_type *type, u8 *sad_pmon_map
 		type->topology = NULL;
 	}
 
+	pci_dev_put(dev);
+
 	return ret;
 }