Merge tag 'efi-urgent' into x86/urgent
authorH. Peter Anvin <hpa@linux.intel.com>
Fri, 21 Jun 2013 10:01:21 +0000 (03:01 -0700)
committerH. Peter Anvin <hpa@linux.intel.com>
Fri, 21 Jun 2013 10:01:21 +0000 (03:01 -0700)
 * Don't leak random kernel memory to EFI variable NVRAM when attempting
   to initiate garbage collection. Also, free the kernel memory when
   we're done with it instead of leaking - Ben Hutchings

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/platform/efi/efi.c

index 5ae2eb09419ec54d2ac7618904c31d961149df43..d2fbcedcf6eaf2fd77179075c1be2c5c4d3d8347 100644 (file)
@@ -1069,7 +1069,10 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
                 * that by attempting to use more space than is available.
                 */
                unsigned long dummy_size = remaining_size + 1024;
-               void *dummy = kmalloc(dummy_size, GFP_ATOMIC);
+               void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
+
+               if (!dummy)
+                       return EFI_OUT_OF_RESOURCES;
 
                status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
                                          EFI_VARIABLE_NON_VOLATILE |
@@ -1089,6 +1092,8 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
                                         0, dummy);
                }
 
+               kfree(dummy);
+
                /*
                 * The runtime code may now have triggered a garbage collection
                 * run, so check the variable info again