ACPICA: Resources: Not a valid resource if buffer length too long
authorBob Moore <robert.moore@intel.com>
Wed, 28 Dec 2016 07:29:28 +0000 (15:29 +0800)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Mon, 2 Jan 2017 22:18:47 +0000 (23:18 +0100)
ACPICA commit 9f76de2d249b18804e35fb55d14b1c2604d627a1
ACPICA commit b2e89d72ef1e9deefd63c3fd1dee90f893575b3a
ACPICA commit 23b5bbe6d78afd3c5abf3adb91a1b098a3000b2e

The declared buffer length must be the same as the length of the
byte initializer list, otherwise not a valid resource descriptor.

Link: https://github.com/acpica/acpica/commit/9f76de2d
Link: https://github.com/acpica/acpica/commit/b2e89d72
Link: https://github.com/acpica/acpica/commit/23b5bbe6
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/acpi/acpica/utresrc.c

index 1de3376da66a5ec4ff19cafa292b0bba32815a1e..2ad99ea3d496deb04e17d4305b82adb0672ef188 100644 (file)
@@ -421,8 +421,10 @@ acpi_ut_walk_aml_resources(struct acpi_walk_state *walk_state,
 
        ACPI_FUNCTION_TRACE(ut_walk_aml_resources);
 
-       /* The absolute minimum resource template is one end_tag descriptor */
-
+       /*
+        * The absolute minimum resource template is one end_tag descriptor.
+        * However, we will treat a lone end_tag as just a simple buffer.
+        */
        if (aml_length < sizeof(struct aml_resource_end_tag)) {
                return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
        }
@@ -454,9 +456,8 @@ acpi_ut_walk_aml_resources(struct acpi_walk_state *walk_state,
                /* Invoke the user function */
 
                if (user_function) {
-                       status =
-                           user_function(aml, length, offset, resource_index,
-                                         context);
+                       status = user_function(aml, length, offset,
+                                              resource_index, context);
                        if (ACPI_FAILURE(status)) {
                                return_ACPI_STATUS(status);
                        }
@@ -480,6 +481,12 @@ acpi_ut_walk_aml_resources(struct acpi_walk_state *walk_state,
                                *context = aml;
                        }
 
+                       /* Check if buffer is defined to be longer than the resource length */
+
+                       if (aml_length > (offset + length)) {
+                               return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+                       }
+
                        /* Normal exit */
 
                        return_ACPI_STATUS(AE_OK);