vendor/acpica/20131218

1 files changed, 130 insertions, 20 deletions

diff --git a/source/components/tables/tbutils.c b/source/components/tables/tbutils.c
index 7c84d5ea427c..159a7d9b0f6f 100644
--- a/source/components/tables/tbutils.c
+++ b/source/components/tables/tbutils.c
@@ -53,6 +53,10 @@
 
 /* Local prototypes */
 
+static ACPI_STATUS
+AcpiTbValidateXsdt (
+    ACPI_PHYSICAL_ADDRESS   Address);
+
 static ACPI_PHYSICAL_ADDRESS
 AcpiTbGetRootTableEntry (
     UINT8                   *TableEntry,
@@ -353,7 +357,7 @@ AcpiTbGetRootTableEntry (
      * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
      * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
      */
-    if (TableEntrySize == sizeof (UINT32))
+    if (TableEntrySize == ACPI_RSDT_ENTRY_SIZE)
     {
         /*
          * 32-bit platform, RSDT: Return 32-bit table entry
@@ -388,6 +392,92 @@ AcpiTbGetRootTableEntry (
 
 /*******************************************************************************
  *
+ * FUNCTION:    AcpiTbValidateXsdt
+ *
+ * PARAMETERS:  Address             - Physical address of the XSDT (from RSDP)
+ *
+ * RETURN:      Status. AE_OK if the table appears to be valid.
+ *
+ * DESCRIPTION: Validate an XSDT to ensure that it is of minimum size and does
+ *              not contain any NULL entries. A problem that is seen in the
+ *              field is that the XSDT exists, but is actually useless because
+ *              of one or more (or all) NULL entries.
+ *
+ ******************************************************************************/
+
+static ACPI_STATUS
+AcpiTbValidateXsdt (
+    ACPI_PHYSICAL_ADDRESS   XsdtAddress)
+{
+    ACPI_TABLE_HEADER       *Table;
+    UINT8                   *NextEntry;
+    ACPI_PHYSICAL_ADDRESS   Address;
+    UINT32                  Length;
+    UINT32                  EntryCount;
+    ACPI_STATUS             Status;
+    UINT32                  i;
+
+
+    /* Get the XSDT length */
+
+    Table = AcpiOsMapMemory (XsdtAddress, sizeof (ACPI_TABLE_HEADER));
+    if (!Table)
+    {
+        return (AE_NO_MEMORY);
+    }
+
+    Length = Table->Length;
+    AcpiOsUnmapMemory (Table, sizeof (ACPI_TABLE_HEADER));
+
+    /*
+     * Minimum XSDT length is the size of the standard ACPI header
+     * plus one physical address entry
+     */
+    if (Length < (sizeof (ACPI_TABLE_HEADER) + ACPI_XSDT_ENTRY_SIZE))
+    {
+        return (AE_INVALID_TABLE_LENGTH);
+    }
+
+    /* Map the entire XSDT */
+
+    Table = AcpiOsMapMemory (XsdtAddress, Length);
+    if (!Table)
+    {
+        return (AE_NO_MEMORY);
+    }
+
+    /* Get the number of entries and pointer to first entry */
+
+    Status = AE_OK;
+    NextEntry = ACPI_ADD_PTR (UINT8, Table, sizeof (ACPI_TABLE_HEADER));
+    EntryCount = (UINT32) ((Table->Length - sizeof (ACPI_TABLE_HEADER)) /
+        ACPI_XSDT_ENTRY_SIZE);
+
+    /* Validate each entry (physical address) within the XSDT */
+
+    for (i = 0; i < EntryCount; i++)
+    {
+        Address = AcpiTbGetRootTableEntry (NextEntry, ACPI_XSDT_ENTRY_SIZE);
+        if (!Address)
+        {
+            /* Detected a NULL entry, XSDT is invalid */
+
+            Status = AE_NULL_ENTRY;
+            break;
+        }
+
+        NextEntry += ACPI_XSDT_ENTRY_SIZE;
+    }
+
+    /* Unmap table */
+
+    AcpiOsUnmapMemory (Table, Length);
+    return (Status);
+}
+
+
+/*******************************************************************************
+ *
  * FUNCTION:    AcpiTbParseRootTable
  *
  * PARAMETERS:  Rsdp                    - Pointer to the RSDP
@@ -421,9 +511,8 @@ AcpiTbParseRootTable (
     ACPI_FUNCTION_TRACE (TbParseRootTable);
 
 
-    /*
-     * Map the entire RSDP and extract the address of the RSDT or XSDT
-     */
+    /* Map the entire RSDP and extract the address of the RSDT or XSDT */
+
     Rsdp = AcpiOsMapMemory (RsdpAddress, sizeof (ACPI_TABLE_RSDP));
     if (!Rsdp)
     {
@@ -433,24 +522,26 @@ AcpiTbParseRootTable (
     AcpiTbPrintTableHeader (RsdpAddress,
         ACPI_CAST_PTR (ACPI_TABLE_HEADER, Rsdp));
 
-    /* Differentiate between RSDT and XSDT root tables */
+    /* Use XSDT if present and not overridden. Otherwise, use RSDT */
 
-    if (Rsdp->Revision > 1 && Rsdp->XsdtPhysicalAddress)
+    if ((Rsdp->Revision > 1) &&
+        Rsdp->XsdtPhysicalAddress &&
+        !AcpiGbl_DoNotUseXsdt)
     {
         /*
-         * Root table is an XSDT (64-bit physical addresses). We must use the
-         * XSDT if the revision is > 1 and the XSDT pointer is present, as per
-         * the ACPI specification.
+         * RSDP contains an XSDT (64-bit physical addresses). We must use
+         * the XSDT if the revision is > 1 and the XSDT pointer is present,
+         * as per the ACPI specification.
          */
         Address = (ACPI_PHYSICAL_ADDRESS) Rsdp->XsdtPhysicalAddress;
-        TableEntrySize = sizeof (UINT64);
+        TableEntrySize = ACPI_XSDT_ENTRY_SIZE;
     }
     else
     {
         /* Root table is an RSDT (32-bit physical addresses) */
 
         Address = (ACPI_PHYSICAL_ADDRESS) Rsdp->RsdtPhysicalAddress;
-        TableEntrySize = sizeof (UINT32);
+        TableEntrySize = ACPI_RSDT_ENTRY_SIZE;
     }
 
     /*
@@ -459,6 +550,24 @@ AcpiTbParseRootTable (
      */
     AcpiOsUnmapMemory (Rsdp, sizeof (ACPI_TABLE_RSDP));
 
+    /*
+     * If it is present and used, validate the XSDT for access/size
+     * and ensure that all table entries are at least non-NULL
+     */
+    if (TableEntrySize == ACPI_XSDT_ENTRY_SIZE)
+    {
+        Status = AcpiTbValidateXsdt (Address);
+        if (ACPI_FAILURE (Status))
+        {
+            ACPI_BIOS_WARNING ((AE_INFO, "XSDT is invalid (%s), using RSDT",
+                AcpiFormatException (Status)));
+
+            /* Fall back to the RSDT */
+
+            Address = (ACPI_PHYSICAL_ADDRESS) Rsdp->RsdtPhysicalAddress;
+            TableEntrySize = ACPI_RSDT_ENTRY_SIZE;
+        }
+    }
 
     /* Map the RSDT/XSDT table header to get the full table length */
 
@@ -470,12 +579,14 @@ AcpiTbParseRootTable (
 
     AcpiTbPrintTableHeader (Address, Table);
 
-    /* Get the length of the full table, verify length and map entire table */
-
+    /*
+     * Validate length of the table, and map entire table.
+     * Minimum length table must contain at least one entry.
+     */
     Length = Table->Length;
     AcpiOsUnmapMemory (Table, sizeof (ACPI_TABLE_HEADER));
 
-    if (Length < sizeof (ACPI_TABLE_HEADER))
+    if (Length < (sizeof (ACPI_TABLE_HEADER) + TableEntrySize))
     {
         ACPI_BIOS_ERROR ((AE_INFO,
             "Invalid table length 0x%X in RSDT/XSDT", Length));
@@ -497,22 +608,21 @@ AcpiTbParseRootTable (
         return_ACPI_STATUS (Status);
     }
 
-    /* Calculate the number of tables described in the root table */
+    /* Get the number of entries and pointer to first entry */
 
     TableCount = (UINT32) ((Table->Length - sizeof (ACPI_TABLE_HEADER)) /
         TableEntrySize);
+    TableEntry = ACPI_ADD_PTR (UINT8, Table, sizeof (ACPI_TABLE_HEADER));
 
     /*
      * First two entries in the table array are reserved for the DSDT
      * and FACS, which are not actually present in the RSDT/XSDT - they
      * come from the FADT
      */
-    TableEntry = ACPI_CAST_PTR (UINT8, Table) + sizeof (ACPI_TABLE_HEADER);
     AcpiGbl_RootTableList.CurrentTableCount = 2;
 
-    /*
-     * Initialize the root table array from the RSDT/XSDT
-     */
+    /* Initialize the root table array from the RSDT/XSDT */
+
     for (i = 0; i < TableCount; i++)
     {
         if (AcpiGbl_RootTableList.CurrentTableCount >=
@@ -554,7 +664,7 @@ AcpiTbParseRootTable (
         AcpiTbInstallTable (AcpiGbl_RootTableList.Tables[i].Address,
             NULL, i);
 
-        /* Special case for FADT - get the DSDT and FACS */
+        /* Special case for FADT - validate it then get the DSDT and FACS */
 
         if (ACPI_COMPARE_NAME (
                 &AcpiGbl_RootTableList.Tables[i].Signature, ACPI_SIG_FADT))