[PATCH AUTOSEL 5.8 078/132] ACPI: Add out of bounds and numa_off protections to pxm_to_node()

Sasha Levin
2020-10-27T00:27:03Z

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

[ Upstream commit 8a3decac087aa897df5af04358c2089e52e70ac4 ]

The function should check the validity of the pxm value before using
it to index the pxm_to_node_map[] array.

Whilst hardening this code may be good in general, the main intent
here is to enable following patches that use this function to replace
acpi_map_pxm_to_node() for non SRAT usecases which should return
NO_NUMA_NODE for PXM entries not matching with those in SRAT.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/acpi/numa/srat.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
index 5be5a977da1bf..8ef44ee0d76bd 100644
--- a/drivers/acpi/numa/srat.c
+++ b/drivers/acpi/numa/srat.c
@@ -31,7 +31,7 @@ int acpi_numa __initdata;

int pxm_to_node(int pxm)
{
- if (pxm < 0)
+ if (pxm < 0 || pxm >= MAX_PXM_DOMAINS || numa_off)
return NUMA_NO_NODE;
return pxm_to_node_map[pxm];
}
--
2.25.1