[PATCH v1] ARM: devtree: Fix /cpus node reference leak

[Yuho Choi <dbgh9129@gmail.com>]

of_find_node_by_path() returns a referenced device node.  In
arm_dt_init_cpu_maps(), the /cpus node is kept across CPU node parsing
but is never released on the success path or on post-acquire error
paths.

Route all exits after the /cpus lookup through a common cleanup label so
the node reference is dropped.

Fixes: a0ae02405076a ("ARM: kernel: add device tree init map function")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
---
 arch/arm/kernel/devtree.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c
index 3b78966e750a..88a072d3b8e1 100644
--- a/arch/arm/kernel/devtree.c
+++ b/arch/arm/kernel/devtree.c
@@ -93,7 +93,7 @@ void __init arm_dt_init_cpu_maps(void)
 		 */
 		if (hwid & ~MPIDR_HWID_BITMASK) {
 			of_node_put(cpu);
-			return;
+			goto out_put_cpus;
 		}
 
 		/*
@@ -107,7 +107,7 @@ void __init arm_dt_init_cpu_maps(void)
 			if (WARN(tmp_map[j] == hwid,
 				 "Duplicate /cpu reg properties in the DT\n")) {
 				of_node_put(cpu);
-				return;
+				goto out_put_cpus;
 			}
 
 		/*
@@ -149,7 +149,7 @@ void __init arm_dt_init_cpu_maps(void)
 
 	if (!bootcpu_valid) {
 		pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n");
-		return;
+		goto out_put_cpus;
 	}
 
 	/*
@@ -162,6 +162,9 @@ void __init arm_dt_init_cpu_maps(void)
 		cpu_logical_map(i) = tmp_map[i];
 		pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i));
 	}
+
+out_put_cpus:
+	of_node_put(cpus);
 }
 
 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
-- 
2.43.0