randstruct: Mark various structs for randomization

This marks many critical kernel structures for randomization. These are
structures that have been targeted in the past in security exploits, or
contain functions pointers, pointers to function pointer tables, lists,
workqueues, ref-counters, credentials, permissions, or are otherwise
sensitive. This initial list was extracted from Brad Spengler/PaX Team's
code in the last public patch of grsecurity/PaX based on my understanding
of the code. Changes or omissions from the original code are mine and
don't reflect the original grsecurity/PaX code.

Left out of this list is task_struct, which requires special handling
and will be covered in a subsequent patch.

Signed-off-by: Kees Cook <keescook@chromium.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/linux/module.h b/include/linux/module.h
index 21f56393602f..d93111d7def6 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -45,7 +45,7 @@ struct module_kobject {
         struct kobject *drivers_dir;
         struct module_param_attrs *mp;
         struct completion *kobj_completion;
-};
+} __randomize_layout;
 
 struct module_attribute {
         struct attribute attr;
@@ -475,7 +475,7 @@ struct module {
         ctor_fn_t *ctors;
         unsigned int num_ctors;
 #endif
-} ____cacheline_aligned;
+} ____cacheline_aligned __randomize_layout;
 #ifndef MODULE_ARCH_INIT
 #define MODULE_ARCH_INIT {}
 #endif