[Patch v4 12/23] ACPI: Enforce stricter checks for address space descriptors

Jiang Liu
2015-02-05T05:42:59Z

Enforce stricter checks for address space descriptors according to
ACPI spec.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
---
drivers/acpi/resource.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 5bf73a9f26d9..57891a621b96 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -192,6 +192,15 @@ static bool acpi_decode_space(struct resource *res,
bool wp = addr->info.mem.write_protect;
u64 len = attr->address_length;

+ /*
+ * Filter out invalid descriptor according to ACPI Spec 5.0, section
+ * 6.4.3.5 Address Space Resource Descriptors.
+ */
+ if ((addr->min_address_fixed != addr->max_address_fixed && len) ||
+ (addr->min_address_fixed && addr->max_address_fixed && !len))
+ pr_debug("ACPI: Invalid address space min_addr_fix %d, max_addr_fix %d, len %llx\n",
+ addr->min_address_fixed, addr->max_address_fixed, len);
+
res->start = attr->minimum;
res->end = attr->maximum;

--
1.7.10.4