diff --git a/20160425/.gitignore b/20160425/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..26087ef26d599af6df0c40a10cd275cd7c579c52
--- /dev/null
+++ b/20160425/.gitignore
@@ -0,0 +1,25 @@
+.chardev-1.ko.cmd
+.chardev-1.mod.o.cmd
+.chardev-1.o.cmd
+.chardev-1write.ko.cmd
+.chardev-1write.mod.o.cmd
+.chardev-1write.o.cmd
+.hellomod-1.ko.cmd
+.hellomod-1.mod.o.cmd
+.hellomod-1.o.cmd
+.tmp_versions/
+Module.symvers
+chardev-1.ko
+chardev-1.mod.c
+chardev-1.mod.o
+chardev-1.o
+chardev-1write.ko
+chardev-1write.mod.c
+chardev-1write.mod.o
+chardev-1write.o
+hellomod-1.ko
+hellomod-1.mod.c
+hellomod-1.mod.o
+hellomod-1.o
+modules.order
+
diff --git a/20160425/Makefile b/20160425/Makefile
index 263a0a5effc01e8110f1626a3d9540e646715deb..6075827316530be068f67b43ec8f020019534fdc 100644
--- a/20160425/Makefile
+++ b/20160425/Makefile
@@ -1,5 +1,6 @@
obj-m += hellomod-1.o
obj-m += chardev-1.o
+obj-m += chardev-1write.o
all:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
diff --git a/20160425/chardev-1write.c b/20160425/chardev-1write.c
new file mode 100644
index 0000000000000000000000000000000000000000..bff85170ae5012eb4bf8e82b690dd379e19ad262
--- /dev/null
+++ b/20160425/chardev-1write.c
@@ -0,0 +1,213 @@
+/* Modified by: Christian Löpke <christian.loepke@hs-bochum.de>
+ * chardev-1write.c: Creates a char device that says Mr. Anderson or a
+ * written name how many times he read from the dev
+ * file.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h> /* for put_user */
+
+/*
+ * Prototypes - this would normally go in a .h file
+ */
+int init_module(void);
+void cleanup_module(void);
+static int device_open(struct inode *, struct file *);
+static int device_release(struct inode *, struct file *);
+static ssize_t device_read(struct file *, char *, size_t, loff_t *);
+static ssize_t device_write(struct file *, const char *, size_t, loff_t *);
+
+#define SUCCESS 0
+#define DEVICE_NAME "chardev" /* Dev name as it appears in /proc/devices */
+#define BUF_LEN 80 /* Max length of the message from the device */
+#define USERBUF_LEN 20 /* Max length for user definable name */
+/*
+ * Global variables are declared as static, so are global within the file.
+ */
+
+static int Major; /* Major number assigned to our device driver */
+static int Device_Open = 0; /* Is device open?
+ * Used to prevent multiple access to device */
+static char msg[BUF_LEN]; /* The msg the device will give when asked */
+static char *msg_Ptr; /* The current char from msg we are writing */
+
+static char msg_username[USERBUF_LEN]; /* User definable name */
+static int told_you_counter = 0; /* Counts the outputs I've made */
+
+static struct file_operations fops = {
+ .read = device_read,
+ .write = device_write,
+ .open = device_open,
+ .release = device_release
+};
+
+/*
+ * This function is called when the module is loaded
+ */
+int init_module(void)
+{
+ Major = register_chrdev(0, DEVICE_NAME, &fops);
+
+ if (Major < 0) {
+ printk( KERN_ALERT
+ "%s: Registering char device failed with %d\n",
+ DEVICE_NAME,
+ Major);
+ return Major;
+ }
+
+ printk( KERN_INFO "%s: I was assigned major number %d. To talk to\n",
+ DEVICE_NAME,
+ Major);
+ printk( KERN_INFO
+ "%s: the driver, create a dev file with\n", DEVICE_NAME);
+ printk( KERN_INFO "%s: 'mknod /dev/%s c %d 0'.\n",
+ DEVICE_NAME,
+ DEVICE_NAME,
+ Major);
+ printk( KERN_INFO
+ "%s: Try various minor numbers. Try to cat and echo to\n",
+ DEVICE_NAME);
+ printk( KERN_INFO "%s: the device file.\n", DEVICE_NAME);
+ printk( KERN_INFO
+ "%s: Remove the device file and module when done.\n",
+ DEVICE_NAME);
+
+ sprintf(msg_username, "Mr. Anderson"); //Setup initial username.
+ return SUCCESS;
+}
+
+/*
+ * This function is called when the module is unloaded
+ */
+void cleanup_module(void)
+{
+ /*
+ * Unregister the device
+ */
+ unregister_chrdev(Major, DEVICE_NAME);
+}
+
+/*
+ * Methods
+ */
+
+/*
+ * Called when a process tries to open the device file, like
+ * "cat /dev/mycharfile"
+ */
+static int device_open(struct inode *inode, struct file *file)
+{
+ if (Device_Open)
+ return -EBUSY;
+
+ Device_Open++;
+ sprintf(msg,
+ "I already told you %d times Hello world!, %s.\n",
+ told_you_counter++,
+ msg_username);
+ msg_Ptr = msg;
+ try_module_get(THIS_MODULE);
+
+ return SUCCESS; /* Device successfully opened */
+}
+
+/*
+ * Called when a process closes the device file.
+ */
+static int device_release(struct inode *inode, struct file *file)
+{
+ Device_Open--; /* We're now ready for our next caller */
+
+ /*
+ * Decrement the usage count, or else once you opened the file, you'll
+ * never get get rid of the module.
+ */
+ module_put(THIS_MODULE);
+
+ return 0; /* Device sucessfully closed */
+}
+
+/*
+ * Called when a process, which already opened the dev file, attempts to
+ * read from it.
+ */
+static ssize_t device_read(struct file *filp, /* see include/linux/fs.h */
+ char *buffer, /* buffer to fill with data */
+ size_t length, /* length of the buffer */
+ loff_t * offset)
+{
+ /*
+ * Number of bytes actually written to the buffer
+ */
+ int bytes_read = 0;
+
+ /*
+ * If we're at the end of the message,
+ * return 0 signifying end of file
+ */
+ if (*msg_Ptr == 0)
+ return 0;
+
+ /*
+ * Actually put the data into the buffer
+ */
+ while (length && *msg_Ptr) {
+
+ /*
+ * The buffer is in the user data segment, not the kernel
+ * segment so "*" assignment won't work. We have to use
+ * put_user which copies data from the kernel data segment to
+ * the user data segment.
+ */
+ put_user(*(msg_Ptr++), buffer++);
+
+ length--;
+ bytes_read++;
+ }
+
+ /*
+ * Most read functions return the number of bytes put into the buffer
+ */
+ return bytes_read;
+}
+
+/*
+ * Called when a process writes to dev file: echo "hi" > /dev/hello
+ */
+static ssize_t
+device_write(struct file *filp, const char *buff, size_t len, loff_t * off)
+{
+ /* Since nobody wants to read I have to correct the already told you
+ counter! */
+ told_you_counter--;
+ if(len >= USERBUF_LEN) {
+ printk( KERN_WARNING
+ "%s: Sorry, your input is too long. Max %d allowed!\n",
+ DEVICE_NAME,
+ USERBUF_LEN);
+ return -ENOMEM; //Return not enaugh memory
+ }
+ else {
+ int i;
+ for(i = 0; i < len; i++) {//Save the given string
+ if(get_user(msg_username[i], buff + i) < 0) { //If returning error code
+ printk(KERN_WARNING
+ "%s: This memory does not belong to you!\n",
+ DEVICE_NAME);
+ return -EFAULT; //Stop reading from userspace.
+ }
+ //msg_username[i] = buff[i]; //Heres was the CRASH
+ //printk(KERN_INFO "Got %c at %d from %d bytes.\n", buff[i], i, len);
+ }
+ for(i = len; i < USERBUF_LEN; i++) //Zeroing the rest of mem
+ msg_username[i] = 0;
+ printk(KERN_INFO "%s: Successfully got %d bytes!\n",
+ DEVICE_NAME, (int)len);
+ if(msg_username[len-1] == '\n') //Got new line terminator ?
+ msg_username[len-1] = 0; //Then terminate it!
+ return len; //Emit successfully stored len bytes
+ }
+}
diff --git a/20160425/dmesgCrash.log b/20160425/dmesgCrash.log
new file mode 100644
index 0000000000000000000000000000000000000000..2dee7a4aa5ee46eacf9ba5cb541d243b8212a1a2
--- /dev/null
+++ b/20160425/dmesgCrash.log
@@ -0,0 +1,83 @@
+Mai 08 20:02:22 archtux kernel: BUG: unable to handle kernel paging
+request at 0000000000ba9810
+Mai 08 20:02:22 archtux kernel: IP: [<ffffffffa05d6138>]
+device_write+0xa8/0xd0 [chardev_1write]
+Mai 08 20:02:22 archtux kernel: PGD 251819067 PUD 251b40067 PMD
+2518e4067 PTE 800000022be53067
+Mai 08 20:02:22 archtux kernel: Oops: 0001 [#4] PREEMPT SMP
+Mai 08 20:02:22 archtux kernel: Modules linked in: chardev_1write(PO)
+ctr ccm fuse snd_hda_codec_hdmi snd_hda_codec_realtek
+snd_hda_codec_generic joydev mousedev arc4 iwlmvm snd_soc_skl
+snd_soc_skl_ipc i915 snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core
+snd_soc_sst_match snd_soc_core snd_compress mac80211 snd_pcm_dmaengine
+ac97_bus drm_kms_helper intel_rapl x86_pkg_temp_thermal snd_hda_intel
+snd_hda_codec intel_powerclamp coretemp snd_hda_core iwlwifi uvcvideo
+videobuf2_vmalloc videobuf2_memops snd_hwdep kvm_intel evdev drm
+input_leds snd_pcm videobuf2_v4l2 cfg80211 intel_gtt led_class
+syscopyarea sysfillrect snd_timer sysimgblt kvm fb_sys_fops snd
+irqbypass mac_hid mei_me videobuf2_core pcspkr i2c_algo_bit shpchp
+soundcore mei serio_raw psmouse videodev btusb hci_uart btrtl btbcm
+btqca btintel media i2c_i801 thermal
+Mai 08 20:02:22 archtux kernel: bluetooth battery video
+pinctrl_sunrisepoint pinctrl_intel rfkill tpm_tis i2c_hid hid
+intel_lpss_acpi intel_lpss tpm fjes processor acpi_pad button ac
+sch_fq_codel ip_tables x_tables sha256_ssse3 sha256_generic hmac drbg
+ansi_cprng algif_skcipher af_alg dm_crypt dm_mod sd_mod atkbd libps2
+crct10dif_pclmul crc32_pclmul crc32c_intel ahci ghash_clmulni_intel
+libahci libata xhci_pci aesni_intel xhci_hcd aes_x86_64 lrw gf128mul
+glue_helper ablk_helper cryptd usbcore scsi_mod usb_common i8042 serio
+ext4 crc16 mbcache jbd2 [last unloaded: chardev_1write]
+Mai 08 20:02:22 archtux kernel: CPU: 2 PID: 3447 Comm: bash Tainted: P
+D O 4.5.2-1-ARCH #1
+Mai 08 20:02:22 archtux kernel: Hardware name: Intel Corporation Skylake
+Platform/U931, BIOS 5.11 04/08/2016
+Mai 08 20:02:22 archtux kernel: task: ffff8802671b0000 ti:
+ffff8802597e0000 task.ti: ffff8802597e0000
+Mai 08 20:02:22 archtux kernel: RIP: 0010:[<ffffffffa05d6138>]
+[<ffffffffa05d6138>] device_write+0xa8/0xd0 [chardev_1write]
+Mai 08 20:02:22 archtux kernel: RSP: 0018:ffff8802597e3e10 EFLAGS:
+00010246
+Mai 08 20:02:22 archtux kernel: RAX: 0000000000000000 RBX:
+0000000000000005 RCX: ffff8802597e3f18
+Mai 08 20:02:22 archtux kernel: RDX: 0000000000000005 RSI:
+0000000000ba9810 RDI: ffff880246f4c900
+Mai 08 20:02:22 archtux kernel: RBP: ffff8802597e3e38 R08:
+0000000000ba9815 R09: 00007ffffffff000
+Mai 08 20:02:22 archtux kernel: R10: 0000000000000004 R11:
+0000000000000246 R12: 0000000000ba9810
+Mai 08 20:02:22 archtux kernel: R13: 0000000000000000 R14:
+ffffffffa05d7090 R15: 0000000000000005
+Mai 08 20:02:22 archtux kernel: FS: 00007f1037d52700(0000)
+GS:ffff880273d00000(0000) knlGS:0000000000000000
+Mai 08 20:02:22 archtux kernel: CS: 0010 DS: 0000 ES: 0000 CR0:
+0000000080050033
+Mai 08 20:02:22 archtux kernel: CR2: 0000000000ba9810 CR3:
+0000000268c22000 CR4: 00000000003406e0
+Mai 08 20:02:22 archtux kernel: Stack:
+Mai 08 20:02:22 archtux kernel: ffff880246f4c900 ffff8802597e3f18
+0000000000ba9810 ffff8802597e3f18
+Mai 08 20:02:22 archtux kernel: 0000000000000000 ffff8802597e3ec0
+ffffffff811ecde7 00000000354527a1
+Mai 08 20:02:22 archtux kernel: 00000000354527a1 000000000000000a
+000000000000000a 0000000000000400
+Mai 08 20:02:22 archtux kernel: Call Trace:
+Mai 08 20:02:22 archtux kernel: [<ffffffff811ecde7>]
+__vfs_write+0x37/0x100
+Mai 08 20:02:22 archtux kernel: [<ffffffff811edc97>]
+vfs_write+0xa7/0x1a0
+Mai 08 20:02:22 archtux kernel: [<ffffffff811eebe5>]
+SyS_write+0x55/0xc0
+Mai 08 20:02:22 archtux kernel: [<ffffffff8120ab43>] ?
+__close_fd+0xa3/0xd0
+Mai 08 20:02:22 archtux kernel: [<ffffffff815b0b6e>]
+entry_SYSCALL_64_fastpath+0x12/0x6d
+Mai 08 20:02:22 archtux kernel: Code: 04 72 5d a0 48 c7 c7 58 70 5d a0
+e8 a0 01 b9 e0 48 c7 c0 f4 ff ff ff eb cc 49 89 f4 41 89 d7 31 c0 45 31
+ed 49 c7 c6 90 70 5d a0 <41> 0f be 34 04 44 89 ea 44 89 f9 41 83 c5 01
+4c 89 f7 e8 6e 01
+Mai 08 20:02:22 archtux kernel: RIP [<ffffffffa05d6138>]
+device_write+0xa8/0xd0 [chardev_1write]
+Mai 08 20:02:22 archtux kernel: RSP <ffff8802597e3e10>
+Mai 08 20:02:22 archtux kernel: CR2: 0000000000ba9810
+Mai 08 20:02:22 archtux kernel: ---[ end trace 2e7525e9567b5a55 ]---
+