iwlwifi: mvm: fix the type we use in the PPAG table validity checks

The value we receive from ACPI is a long long unsigned integer but the
values should be treated as signed char.  When comparing the received
value with ACPI_PPAG_MIN_LB/HB, we were doing an unsigned comparison,
so the negative value would actually be treated as a very high number.

To solve this issue, assign the value to our table of s8's before
making the comparison, so the value is already converted when we do
so.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210210135352.b0ec69f312bc.If77fd9c61a96aa7ef2ac96d935b7efd7df502399@changeid
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/fw.c b/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
index 6a6567a..3bfb80d 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
@@ -965,16 +965,23 @@ read_table:
                        union acpi_object *ent;
 
                        ent = &wifi_pkg->package.elements[idx++];
-                       if (ent->type != ACPI_TYPE_INTEGER ||
-                           (j == 0 && ent->integer.value > ACPI_PPAG_MAX_LB) ||
-                           (j == 0 && ent->integer.value < ACPI_PPAG_MIN_LB) ||
-                           (j != 0 && ent->integer.value > ACPI_PPAG_MAX_HB) ||
-                           (j != 0 && ent->integer.value < ACPI_PPAG_MIN_HB)) {
-                               ppag_table.v1.enabled = cpu_to_le32(0);
+                       if (ent->type != ACPI_TYPE_INTEGER) {
                                ret = -EINVAL;
                                goto out_free;
                        }
+
                        gain[i * num_sub_bands + j] = ent->integer.value;
+
+                       if ((j == 0 &&
+                            (gain[i * num_sub_bands + j] > ACPI_PPAG_MAX_LB ||
+                             gain[i * num_sub_bands + j] < ACPI_PPAG_MIN_LB)) ||
+                           (j != 0 &&
+                            (gain[i * num_sub_bands + j] > ACPI_PPAG_MAX_HB ||
+                             gain[i * num_sub_bands + j] < ACPI_PPAG_MIN_HB))) {
+                               ppag_table.v1.enabled = cpu_to_le32(0);
+                               ret = -EINVAL;
+                               goto out_free;
+                       }
                }
        }
        ret = 0;