[PATCH] lkdtm: Constify the crashtypes table

From: Kees Cook
Date: Fri Oct 20 2017 - 09:31:57 EST


Since nothing in the crashtypes table ever changes, mark it const. Adds
some missing "static" markings as well.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/misc/lkdtm_core.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/misc/lkdtm_core.c b/drivers/misc/lkdtm_core.c
index ed7f0c61c59a..ba92291508dc 100644
--- a/drivers/misc/lkdtm_core.c
+++ b/drivers/misc/lkdtm_core.c
@@ -122,7 +122,7 @@ struct crashtype {
}

/* Define the possible types of crashes that can be triggered. */
-struct crashtype crashtypes[] = {
+static const struct crashtype crashtypes[] = {
CRASHTYPE(PANIC),
CRASHTYPE(BUG),
CRASHTYPE(WARNING),
@@ -188,8 +188,8 @@ struct crashtype crashtypes[] = {

/* Global kprobe entry and crashtype. */
static struct kprobe *lkdtm_kprobe;
-struct crashpoint *lkdtm_crashpoint;
-struct crashtype *lkdtm_crashtype;
+static struct crashpoint *lkdtm_crashpoint;
+static const struct crashtype *lkdtm_crashtype;

/* Module parameters */
static int recur_count = -1;
@@ -212,7 +212,7 @@ MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\


/* Return the crashtype number or NULL if the name is invalid */
-static struct crashtype *find_crashtype(const char *name)
+static const struct crashtype *find_crashtype(const char *name)
{
int i;

@@ -228,7 +228,7 @@ static struct crashtype *find_crashtype(const char *name)
* This is forced noinline just so it distinctly shows up in the stackdump
* which makes validation of expected lkdtm crashes easier.
*/
-static noinline void lkdtm_do_action(struct crashtype *crashtype)
+static noinline void lkdtm_do_action(const struct crashtype *crashtype)
{
if (WARN_ON(!crashtype || !crashtype->func))
return;
@@ -236,7 +236,7 @@ static noinline void lkdtm_do_action(struct crashtype *crashtype)
}

static int lkdtm_register_cpoint(struct crashpoint *crashpoint,
- struct crashtype *crashtype)
+ const struct crashtype *crashtype)
{
int ret;

@@ -300,7 +300,7 @@ static ssize_t lkdtm_debugfs_entry(struct file *f,
size_t count, loff_t *off)
{
struct crashpoint *crashpoint = file_inode(f)->i_private;
- struct crashtype *crashtype = NULL;
+ const struct crashtype *crashtype = NULL;
char *buf;
int err;

@@ -368,7 +368,7 @@ static int lkdtm_debugfs_open(struct inode *inode, struct file *file)
static ssize_t direct_entry(struct file *f, const char __user *user_buf,
size_t count, loff_t *off)
{
- struct crashtype *crashtype;
+ const struct crashtype *crashtype;
char *buf;

if (count >= PAGE_SIZE)
@@ -404,7 +404,7 @@ static struct dentry *lkdtm_debugfs_root;
static int __init lkdtm_module_init(void)
{
struct crashpoint *crashpoint = NULL;
- struct crashtype *crashtype = NULL;
+ const struct crashtype *crashtype = NULL;
int ret = -EINVAL;
int i;

--
2.7.4


--
Kees Cook
Pixel Security