[PATCH] arm64: numa: check the node id before accessing node_to_cpumask_map

[Yunsheng Lin]

Some buggy bios may not set the device' numa id, and dev_to_node
will return -1, which may cause global-out-of-bounds error
detected by KASAN.

This patch changes cpumask_of_node to return cpu_none_mask if the
node is not valid, and sync the cpumask_of_node between the
cpumask_of_node function in numa.h and numa.c.

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
---
 arch/arm64/include/asm/numa.h | 6 ++++++
 arch/arm64/mm/numa.c          | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/numa.h b/arch/arm64/include/asm/numa.h
index 626ad01..da891ed 100644
--- a/arch/arm64/include/asm/numa.h
+++ b/arch/arm64/include/asm/numa.h
@@ -25,6 +25,12 @@ const struct cpumask *cpumask_of_node(int node);
 /* Returns a pointer to the cpumask of CPUs on Node 'node'. */
 static inline const struct cpumask *cpumask_of_node(int node)
 {
+	if (node >= nr_node_ids || node < 0)
+		return cpu_none_mask;
+
+	if (!node_to_cpumask_map[node])
+		return cpu_online_mask;
+
 	return node_to_cpumask_map[node];
 }
 #endif
diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
index 4f241cc..3846313 100644
--- a/arch/arm64/mm/numa.c
+++ b/arch/arm64/mm/numa.c
@@ -46,7 +46,7 @@ EXPORT_SYMBOL(node_to_cpumask_map);
  */
 const struct cpumask *cpumask_of_node(int node)
 {
-	if (WARN_ON(node >= nr_node_ids))
+	if (WARN_ON(node >= nr_node_ids || node < 0))
 		return cpu_none_mask;
 
 	if (WARN_ON(node_to_cpumask_map[node] == NULL))
-- 
2.8.1