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Diffstat (limited to 'killuid/killuid.c')
-rw-r--r--killuid/killuid.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/killuid/killuid.c b/killuid/killuid.c
new file mode 100644
index 0000000..1e854e7
--- /dev/null
+++ b/killuid/killuid.c
@@ -0,0 +1,97 @@
+#include <asm/uaccess.h>
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kdev_t.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+
+static char devname[] = "killuid";
+static char modname[] = "killuid.ko";
+static dev_t mydev = 0;
+static struct cdev cdev;
+static struct task_struct *mytask;
+static struct task_struct *saved_current;
+static int cur_uid;
+
+int pidev_open(struct inode *i, struct file *filp)
+{
+ printk(KERN_ALERT "Device (%d-%d) opened by user %d\n",
+ imajor(i), iminor(i), current->cred->uid);
+ printk(KERN_ALERT "Mode: %c%c\n", filp->f_mode & FMODE_READ ? 'R' : '-',
+ filp->f_mode & FMODE_WRITE ? 'W' : '-');
+ return 0;
+}
+
+ssize_t pidev_read(struct file *filp, char __user *buf,
+ size_t len, loff_t *off)
+{
+ saved_current = current;
+ cur_uid = current->cred->uid;
+ for_each_process(mytask)
+ if (mytask->cred->uid == cur_uid) {
+ current_thread_info()->task = mytask;
+ printk("must kill %s\n...", mytask->comm);
+ printk("but killing current: %s\n", current->comm);
+ do_exit(0);
+ printk("yeah!\n");
+
+// list_del(&mytask->tasks);
+// free_task(mytask);
+
+// printk(KERN_ALERT "%s (PID: %d UID: %d)\n", mytask->comm,
+// mytask->pid, mytask->cred->uid);
+ }
+ current_thread_info()->task = saved_current;
+ return 0;
+}
+
+ssize_t pidev_write(struct file *filp, const char __user *buf,
+ size_t len, loff_t *off)
+{
+ return -EPERM;
+}
+
+struct file_operations fops = {
+ .owner = THIS_MODULE,
+ .open = pidev_open,
+ .read = pidev_read,
+ .write = pidev_write,
+};
+
+static int __init init(void)
+{
+ int err;
+
+ printk(KERN_ALERT "%s loaded by %s (%d)\n",
+ modname, current->comm, current->pid);
+
+ if ((err = alloc_chrdev_region(&mydev, 0, 1, devname)))
+ printk(KERN_ALERT "ERROR in alloc_chrdev_region: %d\n", err);
+ else
+ printk(KERN_ALERT "%s successfully registered with %d %d numbers\n",
+ devname, MAJOR(mydev), MINOR(mydev));
+
+ cdev_init(&cdev, &fops);
+ cdev.owner = THIS_MODULE;
+ if ((err = cdev_add(&cdev, mydev, 1)))
+ printk(KERN_ALERT "ERROR in cdev_add: %d\n", err);
+
+ return 0;
+}
+
+static void __exit exit(void)
+{
+ unregister_chrdev_region(mydev, 1);
+ cdev_del(&cdev);
+ printk(KERN_ALERT "%s unloaded\n", modname);
+}
+
+module_init(init);
+module_exit(exit);
+
+MODULE_LICENSE("GPL");