initial_commit

1 files changed, 691 insertions, 0 deletions

diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
new file mode 100644
index 00000000..150cd706
--- /dev/null
+++ b/drivers/misc/lkdtm.c
@@ -0,0 +1,691 @@
+/*
+ * Kprobe module for testing crash dumps
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) IBM Corporation, 2006
+ *
+ * Author: Ankita Garg <ankita@in.ibm.com>
+ *
+ * This module induces system failures at predefined crashpoints to
+ * evaluate the reliability of crash dumps obtained using different dumping
+ * solutions.
+ *
+ * It is adapted from the Linux Kernel Dump Test Tool by
+ * Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
+ *
+ * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net>
+ *
+ * See Documentation/fault-injection/provoke-crashes.txt for instructions
+ */
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/buffer_head.h>
+#include <linux/kprobes.h>
+#include <linux/list.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/hrtimer.h>
+#include <linux/slab.h>
+#include <scsi/scsi_cmnd.h>
+#include <linux/debugfs.h>
+
+#ifdef CONFIG_IDE
+#include <linux/ide.h>
+#endif
+
+#define DEFAULT_COUNT 10
+#define REC_NUM_DEFAULT 10
+
+enum cname {
+	CN_INVALID,
+	CN_INT_HARDWARE_ENTRY,
+	CN_INT_HW_IRQ_EN,
+	CN_INT_TASKLET_ENTRY,
+	CN_FS_DEVRW,
+	CN_MEM_SWAPOUT,
+	CN_TIMERADD,
+	CN_SCSI_DISPATCH_CMD,
+	CN_IDE_CORE_CP,
+	CN_DIRECT,
+};
+
+enum ctype {
+	CT_NONE,
+	CT_PANIC,
+	CT_BUG,
+	CT_EXCEPTION,
+	CT_LOOP,
+	CT_OVERFLOW,
+	CT_CORRUPT_STACK,
+	CT_UNALIGNED_LOAD_STORE_WRITE,
+	CT_OVERWRITE_ALLOCATION,
+	CT_WRITE_AFTER_FREE,
+	CT_SOFTLOCKUP,
+	CT_HARDLOCKUP,
+	CT_HUNG_TASK,
+};
+
+static char* cp_name[] = {
+	"INT_HARDWARE_ENTRY",
+	"INT_HW_IRQ_EN",
+	"INT_TASKLET_ENTRY",
+	"FS_DEVRW",
+	"MEM_SWAPOUT",
+	"TIMERADD",
+	"SCSI_DISPATCH_CMD",
+	"IDE_CORE_CP",
+	"DIRECT",
+};
+
+static char* cp_type[] = {
+	"PANIC",
+	"BUG",
+	"EXCEPTION",
+	"LOOP",
+	"OVERFLOW",
+	"CORRUPT_STACK",
+	"UNALIGNED_LOAD_STORE_WRITE",
+	"OVERWRITE_ALLOCATION",
+	"WRITE_AFTER_FREE",
+	"SOFTLOCKUP",
+	"HARDLOCKUP",
+	"HUNG_TASK",
+};
+
+static struct jprobe lkdtm;
+
+static int lkdtm_parse_commandline(void);
+static void lkdtm_handler(void);
+
+static char* cpoint_name;
+static char* cpoint_type;
+static int cpoint_count = DEFAULT_COUNT;
+static int recur_count = REC_NUM_DEFAULT;
+
+static enum cname cpoint = CN_INVALID;
+static enum ctype cptype = CT_NONE;
+static int count = DEFAULT_COUNT;
+static DEFINE_SPINLOCK(count_lock);
+
+module_param(recur_count, int, 0644);
+MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\
+				 "default is 10");
+module_param(cpoint_name, charp, 0444);
+MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
+module_param(cpoint_type, charp, 0444);
+MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
+				"hitting the crash point");
+module_param(cpoint_count, int, 0644);
+MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
+				"crash point is to be hit to trigger action");
+
+static unsigned int jp_do_irq(unsigned int irq)
+{
+	lkdtm_handler();
+	jprobe_return();
+	return 0;
+}
+
+static irqreturn_t jp_handle_irq_event(unsigned int irq,
+				       struct irqaction *action)
+{
+	lkdtm_handler();
+	jprobe_return();
+	return 0;
+}
+
+static void jp_tasklet_action(struct softirq_action *a)
+{
+	lkdtm_handler();
+	jprobe_return();
+}
+
+static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
+{
+	lkdtm_handler();
+	jprobe_return();
+}
+
+struct scan_control;
+
+static unsigned long jp_shrink_inactive_list(unsigned long max_scan,
+					     struct zone *zone,
+					     struct scan_control *sc)
+{
+	lkdtm_handler();
+	jprobe_return();
+	return 0;
+}
+
+static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
+			    const enum hrtimer_mode mode)
+{
+	lkdtm_handler();
+	jprobe_return();
+	return 0;
+}
+
+static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd)
+{
+	lkdtm_handler();
+	jprobe_return();
+	return 0;
+}
+
+#ifdef CONFIG_IDE
+int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file,
+			struct block_device *bdev, unsigned int cmd,
+			unsigned long arg)
+{
+	lkdtm_handler();
+	jprobe_return();
+	return 0;
+}
+#endif
+
+/* Return the crashpoint number or NONE if the name is invalid */
+static enum ctype parse_cp_type(const char *what, size_t count)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(cp_type); i++) {
+		if (!strcmp(what, cp_type[i]))
+			return i + 1;
+	}
+
+	return CT_NONE;
+}
+
+static const char *cp_type_to_str(enum ctype type)
+{
+	if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type))
+		return "None";
+
+	return cp_type[type - 1];
+}
+
+static const char *cp_name_to_str(enum cname name)
+{
+	if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name))
+		return "INVALID";
+
+	return cp_name[name - 1];
+}
+
+
+static int lkdtm_parse_commandline(void)
+{
+	int i;
+	unsigned long flags;
+
+	if (cpoint_count < 1 || recur_count < 1)
+		return -EINVAL;
+
+	spin_lock_irqsave(&count_lock, flags);
+	count = cpoint_count;
+	spin_unlock_irqrestore(&count_lock, flags);
+
+	/* No special parameters */
+	if (!cpoint_type && !cpoint_name)
+		return 0;
+
+	/* Neither or both of these need to be set */
+	if (!cpoint_type || !cpoint_name)
+		return -EINVAL;
+
+	cptype = parse_cp_type(cpoint_type, strlen(cpoint_type));
+	if (cptype == CT_NONE)
+		return -EINVAL;
+
+	for (i = 0; i < ARRAY_SIZE(cp_name); i++) {
+		if (!strcmp(cpoint_name, cp_name[i])) {
+			cpoint = i + 1;
+			return 0;
+		}
+	}
+
+	/* Could not find a valid crash point */
+	return -EINVAL;
+}
+
+static int recursive_loop(int a)
+{
+	char buf[1024];
+
+	memset(buf,0xFF,1024);
+	recur_count--;
+	if (!recur_count)
+		return 0;
+	else
+        	return recursive_loop(a);
+}
+
+static void lkdtm_do_action(enum ctype which)
+{
+	switch (which) {
+	case CT_PANIC:
+		panic("dumptest");
+		break;
+	case CT_BUG:
+		BUG();
+		break;
+	case CT_EXCEPTION:
+		*((int *) 0) = 0;
+		break;
+	case CT_LOOP:
+		for (;;)
+			;
+		break;
+	case CT_OVERFLOW:
+		(void) recursive_loop(0);
+		break;
+	case CT_CORRUPT_STACK: {
+		volatile u32 data[8];
+		volatile u32 *p = data;
+
+		p[12] = 0x12345678;
+		break;
+	}
+	case CT_UNALIGNED_LOAD_STORE_WRITE: {
+		static u8 data[5] __attribute__((aligned(4))) = {1, 2,
+				3, 4, 5};
+		u32 *p;
+		u32 val = 0x12345678;
+
+		p = (u32 *)(data + 1);
+		if (*p == 0)
+			val = 0x87654321;
+		*p = val;
+		 break;
+	}
+	case CT_OVERWRITE_ALLOCATION: {
+		size_t len = 1020;
+		u32 *data = kmalloc(len, GFP_KERNEL);
+
+		data[1024 / sizeof(u32)] = 0x12345678;
+		kfree(data);
+		break;
+	}
+	case CT_WRITE_AFTER_FREE: {
+		size_t len = 1024;
+		u32 *data = kmalloc(len, GFP_KERNEL);
+
+		kfree(data);
+		schedule();
+		memset(data, 0x78, len);
+		break;
+	}
+	case CT_SOFTLOCKUP:
+		preempt_disable();
+		for (;;)
+			cpu_relax();
+		break;
+	case CT_HARDLOCKUP:
+		local_irq_disable();
+		for (;;)
+			cpu_relax();
+		break;
+	case CT_HUNG_TASK:
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule();
+		break;
+	case CT_NONE:
+	default:
+		break;
+	}
+
+}
+
+static void lkdtm_handler(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&count_lock, flags);
+	count--;
+	printk(KERN_INFO "lkdtm: Crash point %s of type %s hit, trigger in %d rounds\n",
+			cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
+
+	if (count == 0) {
+		lkdtm_do_action(cptype);
+		count = cpoint_count;
+	}
+	spin_unlock_irqrestore(&count_lock, flags);
+}
+
+static int lkdtm_register_cpoint(enum cname which)
+{
+	int ret;
+
+	cpoint = CN_INVALID;
+	if (lkdtm.entry != NULL)
+		unregister_jprobe(&lkdtm);
+
+	switch (which) {
+	case CN_DIRECT:
+		lkdtm_do_action(cptype);
+		return 0;
+	case CN_INT_HARDWARE_ENTRY:
+		lkdtm.kp.symbol_name = "do_IRQ";
+		lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
+		break;
+	case CN_INT_HW_IRQ_EN:
+		lkdtm.kp.symbol_name = "handle_IRQ_event";
+		lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
+		break;
+	case CN_INT_TASKLET_ENTRY:
+		lkdtm.kp.symbol_name = "tasklet_action";
+		lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
+		break;
+	case CN_FS_DEVRW:
+		lkdtm.kp.symbol_name = "ll_rw_block";
+		lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
+		break;
+	case CN_MEM_SWAPOUT:
+		lkdtm.kp.symbol_name = "shrink_inactive_list";
+		lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
+		break;
+	case CN_TIMERADD:
+		lkdtm.kp.symbol_name = "hrtimer_start";
+		lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
+		break;
+	case CN_SCSI_DISPATCH_CMD:
+		lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
+		lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
+		break;
+	case CN_IDE_CORE_CP:
+#ifdef CONFIG_IDE
+		lkdtm.kp.symbol_name = "generic_ide_ioctl";
+		lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl;
+#else
+		printk(KERN_INFO "lkdtm: Crash point not available\n");
+		return -EINVAL;
+#endif
+		break;
+	default:
+		printk(KERN_INFO "lkdtm: Invalid Crash Point\n");
+		return -EINVAL;
+	}
+
+	cpoint = which;
+	if ((ret = register_jprobe(&lkdtm)) < 0) {
+		printk(KERN_INFO "lkdtm: Couldn't register jprobe\n");
+		cpoint = CN_INVALID;
+	}
+
+	return ret;
+}
+
+static ssize_t do_register_entry(enum cname which, struct file *f,
+		const char __user *user_buf, size_t count, loff_t *off)
+{
+	char *buf;
+	int err;
+
+	if (count >= PAGE_SIZE)
+		return -EINVAL;
+
+	buf = (char *)__get_free_page(GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+	if (copy_from_user(buf, user_buf, count)) {
+		free_page((unsigned long) buf);
+		return -EFAULT;
+	}
+	/* NULL-terminate and remove enter */
+	buf[count] = '\0';
+	strim(buf);
+
+	cptype = parse_cp_type(buf, count);
+	free_page((unsigned long) buf);
+
+	if (cptype == CT_NONE)
+		return -EINVAL;
+
+	err = lkdtm_register_cpoint(which);
+	if (err < 0)
+		return err;
+
+	*off += count;
+
+	return count;
+}
+
+/* Generic read callback that just prints out the available crash types */
+static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf,
+		size_t count, loff_t *off)
+{
+	char *buf;
+	int i, n, out;
+
+	buf = (char *)__get_free_page(GFP_KERNEL);
+
+	n = snprintf(buf, PAGE_SIZE, "Available crash types:\n");
+	for (i = 0; i < ARRAY_SIZE(cp_type); i++)
+		n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]);
+	buf[n] = '\0';
+
+	out = simple_read_from_buffer(user_buf, count, off,
+				      buf, n);
+	free_page((unsigned long) buf);
+
+	return out;
+}
+
+static int lkdtm_debugfs_open(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+
+static ssize_t int_hardware_entry(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off);
+}
+
+static ssize_t int_hw_irq_en(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off);
+}
+
+static ssize_t int_tasklet_entry(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off);
+}
+
+static ssize_t fs_devrw_entry(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_FS_DEVRW, f, buf, count, off);
+}
+
+static ssize_t mem_swapout_entry(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off);
+}
+
+static ssize_t timeradd_entry(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_TIMERADD, f, buf, count, off);
+}
+
+static ssize_t scsi_dispatch_cmd_entry(struct file *f,
+		const char __user *buf, size_t count, loff_t *off)
+{
+	return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off);
+}
+
+static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf,
+		size_t count, loff_t *off)
+{
+	return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off);
+}
+
+/* Special entry to just crash directly. Available without KPROBEs */
+static ssize_t direct_entry(struct file *f, const char __user *user_buf,
+		size_t count, loff_t *off)
+{
+	enum ctype type;
+	char *buf;
+
+	if (count >= PAGE_SIZE)
+		return -EINVAL;
+	if (count < 1)
+		return -EINVAL;
+
+	buf = (char *)__get_free_page(GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+	if (copy_from_user(buf, user_buf, count)) {
+		free_page((unsigned long) buf);
+		return -EFAULT;
+	}
+	/* NULL-terminate and remove enter */
+	buf[count] = '\0';
+	strim(buf);
+
+	type = parse_cp_type(buf, count);
+	free_page((unsigned long) buf);
+	if (type == CT_NONE)
+		return -EINVAL;
+
+	printk(KERN_INFO "lkdtm: Performing direct entry %s\n",
+			cp_type_to_str(type));
+	lkdtm_do_action(type);
+	*off += count;
+
+	return count;
+}
+
+struct crash_entry {
+	const char *name;
+	const struct file_operations fops;
+};
+
+static const struct crash_entry crash_entries[] = {
+	{"DIRECT", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = direct_entry} },
+	{"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = int_hardware_entry} },
+	{"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = int_hw_irq_en} },
+	{"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = int_tasklet_entry} },
+	{"FS_DEVRW", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = fs_devrw_entry} },
+	{"MEM_SWAPOUT", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = mem_swapout_entry} },
+	{"TIMERADD", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = timeradd_entry} },
+	{"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = scsi_dispatch_cmd_entry} },
+	{"IDE_CORE_CP",	{.read = lkdtm_debugfs_read,
+			.llseek = generic_file_llseek,
+			.open = lkdtm_debugfs_open,
+			.write = ide_core_cp_entry} },
+};
+
+static struct dentry *lkdtm_debugfs_root;
+
+static int __init lkdtm_module_init(void)
+{
+	int ret = -EINVAL;
+	int n_debugfs_entries = 1; /* Assume only the direct entry */
+	int i;
+
+	/* Register debugfs interface */
+	lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL);
+	if (!lkdtm_debugfs_root) {
+		printk(KERN_ERR "lkdtm: creating root dir failed\n");
+		return -ENODEV;
+	}
+
+#ifdef CONFIG_KPROBES
+	n_debugfs_entries = ARRAY_SIZE(crash_entries);
+#endif
+
+	for (i = 0; i < n_debugfs_entries; i++) {
+		const struct crash_entry *cur = &crash_entries[i];
+		struct dentry *de;
+
+		de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root,
+				NULL, &cur->fops);
+		if (de == NULL) {
+			printk(KERN_ERR "lkdtm: could not create %s\n",
+					cur->name);
+			goto out_err;
+		}
+	}
+
+	if (lkdtm_parse_commandline() == -EINVAL) {
+		printk(KERN_INFO "lkdtm: Invalid command\n");
+		goto out_err;
+	}
+
+	if (cpoint != CN_INVALID && cptype != CT_NONE) {
+		ret = lkdtm_register_cpoint(cpoint);
+		if (ret < 0) {
+			printk(KERN_INFO "lkdtm: Invalid crash point %d\n",
+					cpoint);
+			goto out_err;
+		}
+		printk(KERN_INFO "lkdtm: Crash point %s of type %s registered\n",
+				cpoint_name, cpoint_type);
+	} else {
+		printk(KERN_INFO "lkdtm: No crash points registered, enable through debugfs\n");
+	}
+
+	return 0;
+
+out_err:
+	debugfs_remove_recursive(lkdtm_debugfs_root);
+	return ret;
+}
+
+static void __exit lkdtm_module_exit(void)
+{
+	debugfs_remove_recursive(lkdtm_debugfs_root);
+
+	unregister_jprobe(&lkdtm);
+	printk(KERN_INFO "lkdtm: Crash point unregistered\n");
+}
+
+module_init(lkdtm_module_init);
+module_exit(lkdtm_module_exit);
+
+MODULE_LICENSE("GPL");