[PATCH v2 1/9] arm64: numa: check the node id consistently for arm64

[Yunsheng Lin <linyunsheng@huawei.com>]

According to Section 6.2.14 from ACPI spec 6.3 [1], the setting
of proximity domain is optional, as below:

This optional object is used to describe proximity domain
associations within a machine. _PXM evaluates to an integer
that identifies a device as belonging to a Proximity Domain
defined in the System Resource Affinity Table (SRAT).

When enabling KASAN and bios has not implemented the proximity
domain of the hns3 device, there is a global-out-of-bounds error
below:

[   42.970381] ==================================================================
[   42.977595] BUG: KASAN: global-out-of-bounds in __bitmap_weight+0x48/0xb0
[   42.984370] Read of size 8 at addr ffff20008cdf8790 by task kworker/0:1/13
[   42.991230]
[   42.992712] CPU: 0 PID: 13 Comm: kworker/0:1 Tainted: G           O      5.2.0-rc4-g8bde06a-dirty #3
[   43.001830] Hardware name: Huawei TaiShan 2280 V2/BC82AMDA, BIOS TA BIOS 2280-A CS V2.B050.01 08/08/2019
[   43.011298] Workqueue: events work_for_cpu_fn
[   43.015643] Call trace:
[   43.018078]  dump_backtrace+0x0/0x1e8
[   43.021727]  show_stack+0x14/0x20
[   43.025031]  dump_stack+0xc4/0xfc
[   43.028335]  print_address_description+0x178/0x270
[   43.033113]  __kasan_report+0x164/0x1b8
[   43.036936]  kasan_report+0xc/0x18
[   43.040325]  __asan_load8+0x84/0xa8
[   43.043801]  __bitmap_weight+0x48/0xb0
[   43.047552]  hclge_init_ae_dev+0x988/0x1e78 [hclge]
[   43.052418]  hnae3_register_ae_dev+0xcc/0x278 [hnae3]
[   43.057467]  hns3_probe+0xe0/0x120 [hns3]
[   43.061464]  local_pci_probe+0x74/0xf0
[   43.065200]  work_for_cpu_fn+0x2c/0x48
[   43.068937]  process_one_work+0x3c0/0x878
[   43.072934]  worker_thread+0x400/0x670
[   43.076670]  kthread+0x1b0/0x1b8
[   43.079885]  ret_from_fork+0x10/0x18
[   43.083446]
[   43.084925] The buggy address belongs to the variable:
[   43.090052]  numa_distance+0x30/0x40
[   43.093613]
[   43.095091] Memory state around the buggy address:
[   43.099870]  ffff20008cdf8680: fa fa fa fa 04 fa fa fa fa fa fa fa 00 00 fa fa
[   43.107078]  ffff20008cdf8700: fa fa fa fa 04 fa fa fa fa fa fa fa 00 fa fa fa
[   43.114286] >ffff20008cdf8780: fa fa fa fa 00 00 00 00 00 00 00 00 fa fa fa fa
[   43.121494]                          ^
[   43.125230]  ffff20008cdf8800: 01 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa
[   43.132439]  ffff20008cdf8880: fa fa fa fa fa fa fa fa 00 00 fa fa fa fa fa fa
[   43.139646] ==================================================================

This patch checks node id with the below case before returning
node_to_cpumask_map[node]:
1. if node_id >= nr_node_ids, return cpu_none_mask
2. if node_id < 0, return cpu_online_mask
3. if node_to_cpumask_map[node_id] is NULL, return cpu_online_mask

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
---
 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..65a0ef6 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)
+		return cpu_none_mask;
+
+	if (node < 0 || !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..7eca267 100644
--- a/arch/arm64/mm/numa.c
+++ b/arch/arm64/mm/numa.c
@@ -49,7 +49,7 @@ const struct cpumask *cpumask_of_node(int node)
 	if (WARN_ON(node >= nr_node_ids))
 		return cpu_none_mask;
 
-	if (WARN_ON(node_to_cpumask_map[node] == NULL))
+	if (WARN_ON(node < 0 || !node_to_cpumask_map[node]))
 		return cpu_online_mask;
 
 	return node_to_cpumask_map[node];
-- 
2.8.1