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>
diff --git a/fs/mount.h b/fs/mount.h
index bf1fda6..e406b28 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -16,7 +16,7 @@ struct mnt_namespace {
u64 event;
unsigned int mounts; /* # of mounts in the namespace */
unsigned int pending_mounts;
-};
+} __randomize_layout;
struct mnt_pcp {
int mnt_count;
@@ -68,7 +68,7 @@ struct mount {
struct hlist_head mnt_pins;
struct fs_pin mnt_umount;
struct dentry *mnt_ex_mountpoint;
-};
+} __randomize_layout;
#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
diff --git a/fs/namei.c b/fs/namei.c
index 6571a5f..1764620 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -524,7 +524,7 @@ struct nameidata {
struct inode *link_inode;
unsigned root_seq;
int dfd;
-};
+} __randomize_layout;
static void set_nameidata(struct nameidata *p, int dfd, struct filename *name)
{
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index c5ae09b..07b1631 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -51,7 +51,7 @@ struct proc_dir_entry {
spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
u8 namelen;
char name[];
-};
+} __randomize_layout;
union proc_op {
int (*proc_get_link)(struct dentry *, struct path *);
@@ -70,7 +70,7 @@ struct proc_inode {
struct list_head sysctl_inodes;
const struct proc_ns_operations *ns_ops;
struct inode vfs_inode;
-};
+} __randomize_layout;
/*
* General functions
@@ -279,7 +279,7 @@ struct proc_maps_private {
#ifdef CONFIG_NUMA
struct mempolicy *task_mempolicy;
#endif
-};
+} __randomize_layout;
struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
