acpi: make bios_linker_loader_add_pointer() API offset based

cleanup bios_linker_loader_add_pointer() API by switching
arguments to taking offsets relative to corresponding files
instead of doing pointer arithmetic on behalf of user which
were confusing.

Also make offset inside of source file explicit in API
so that user won't have to manually set it in
destination file blob and while at it add additional
boundary checks.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 12 insertions, 10 deletions

diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
index 66e9bf8f06..d02583747f 100644
--- a/hw/acpi/aml-build.c
+++ b/hw/acpi/aml-build.c
@@ -1534,7 +1534,7 @@ unsigned acpi_data_len(GArray *table)
 
 void acpi_add_table(GArray *table_offsets, GArray *table_data)
 {
-    uint32_t offset = cpu_to_le32(table_data->len);
+    uint32_t offset = table_data->len;
     g_array_append_val(table_offsets, offset);
 }
 
@@ -1559,21 +1559,23 @@ void
 build_rsdt(GArray *table_data, BIOSLinker *linker, GArray *table_offsets,
            const char *oem_id, const char *oem_table_id)
 {
-    AcpiRsdtDescriptorRev1 *rsdt;
-    size_t rsdt_len;
     int i;
-    const int table_data_len = (sizeof(uint32_t) * table_offsets->len);
+    unsigned rsdt_entries_offset;
+    AcpiRsdtDescriptorRev1 *rsdt;
+    const unsigned table_data_len = (sizeof(uint32_t) * table_offsets->len);
+    const unsigned rsdt_entry_size = sizeof(rsdt->table_offset_entry[0]);
+    const size_t rsdt_len = sizeof(*rsdt) + table_data_len;
 
-    rsdt_len = sizeof(*rsdt) + table_data_len;
     rsdt = acpi_data_push(table_data, rsdt_len);
-    memcpy(rsdt->table_offset_entry, table_offsets->data, table_data_len);
+    rsdt_entries_offset = (char *)rsdt->table_offset_entry - table_data->data;
     for (i = 0; i < table_offsets->len; ++i) {
+        uint32_t ref_tbl_offset = g_array_index(table_offsets, uint32_t, i);
+        uint32_t rsdt_entry_offset = rsdt_entries_offset + rsdt_entry_size * i;
+
         /* rsdt->table_offset_entry to be filled by Guest linker */
         bios_linker_loader_add_pointer(linker,
-                                       ACPI_BUILD_TABLE_FILE,
-                                       ACPI_BUILD_TABLE_FILE,
-                                       &rsdt->table_offset_entry[i],
-                                       sizeof(uint32_t));
+            ACPI_BUILD_TABLE_FILE, rsdt_entry_offset, rsdt_entry_size,
+            ACPI_BUILD_TABLE_FILE, ref_tbl_offset);
     }
     build_header(linker, table_data,
                  (void *)rsdt, "RSDT", rsdt_len, 1, oem_id, oem_table_id);