Revert "Restrict /dev/mem and /dev/kmem when module loading is restricted"

BugLink: https://bugs.launchpad.net/bugs/1884159

This reverts commit 517d6c3a to
backport an updated version.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Andrea Righi <andrea.righi@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/char/mem.c

@@ -188,9 +188,6 @@ static ssize_t write_mem(struct file *file, const char __user *buf,
 	if (p != *ppos)
 		return -EFBIG;
 
-	if (secure_modules())
-		return -EPERM;
-
 	if (!valid_phys_addr_range(p, count))
 		return -EFAULT;
 
@@ -558,9 +555,6 @@ static ssize_t write_kmem(struct file *file, const char __user *buf,
 	char *kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
 	int err = 0;
 
-	if (secure_modules())
-		return -EPERM;
-
 	if (p < (unsigned long) high_memory) {
 		unsigned long to_write = min_t(unsigned long, count,
 					       (unsigned long)high_memory - p);