1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46#include <linux/kernel.h>
47#include <linux/fs.h>
48#include <linux/module.h>
49#include <linux/buffer_head.h>
50#include <linux/kprobes.h>
51#include <linux/list.h>
52#include <linux/init.h>
53#include <linux/interrupt.h>
54#include <linux/hrtimer.h>
55#include <scsi/scsi_cmnd.h>
56
57#ifdef CONFIG_IDE
58#include <linux/ide.h>
59#endif
60
61#define NUM_CPOINTS 8
62#define NUM_CPOINT_TYPES 5
63#define DEFAULT_COUNT 10
64#define REC_NUM_DEFAULT 10
65
66enum cname {
67 INVALID,
68 INT_HARDWARE_ENTRY,
69 INT_HW_IRQ_EN,
70 INT_TASKLET_ENTRY,
71 FS_DEVRW,
72 MEM_SWAPOUT,
73 TIMERADD,
74 SCSI_DISPATCH_CMD,
75 IDE_CORE_CP
76};
77
78enum ctype {
79 NONE,
80 PANIC,
81 BUG,
82 EXCEPTION,
83 LOOP,
84 OVERFLOW
85};
86
87static char* cp_name[] = {
88 "INT_HARDWARE_ENTRY",
89 "INT_HW_IRQ_EN",
90 "INT_TASKLET_ENTRY",
91 "FS_DEVRW",
92 "MEM_SWAPOUT",
93 "TIMERADD",
94 "SCSI_DISPATCH_CMD",
95 "IDE_CORE_CP"
96};
97
98static char* cp_type[] = {
99 "PANIC",
100 "BUG",
101 "EXCEPTION",
102 "LOOP",
103 "OVERFLOW"
104};
105
106static struct jprobe lkdtm;
107
108static int lkdtm_parse_commandline(void);
109static void lkdtm_handler(void);
110
111static char* cpoint_name;
112static char* cpoint_type;
113static int cpoint_count = DEFAULT_COUNT;
114static int recur_count = REC_NUM_DEFAULT;
115
116static enum cname cpoint = INVALID;
117static enum ctype cptype = NONE;
118static int count = DEFAULT_COUNT;
119
120module_param(recur_count, int, 0644);
121MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test, "\
122 "default is 10");
123module_param(cpoint_name, charp, 0644);
124MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
125module_param(cpoint_type, charp, 0644);
126MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
127 "hitting the crash point");
128module_param(cpoint_count, int, 0644);
129MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\
130 "crash point is to be hit to trigger action");
131
132static unsigned int jp_do_irq(unsigned int irq)
133{
134 lkdtm_handler();
135 jprobe_return();
136 return 0;
137}
138
139static irqreturn_t jp_handle_irq_event(unsigned int irq,
140 struct irqaction *action)
141{
142 lkdtm_handler();
143 jprobe_return();
144 return 0;
145}
146
147static void jp_tasklet_action(struct softirq_action *a)
148{
149 lkdtm_handler();
150 jprobe_return();
151}
152
153static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
154{
155 lkdtm_handler();
156 jprobe_return();
157}
158
159struct scan_control;
160
161static unsigned long jp_shrink_inactive_list(unsigned long max_scan,
162 struct zone *zone,
163 struct scan_control *sc)
164{
165 lkdtm_handler();
166 jprobe_return();
167 return 0;
168}
169
170static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim,
171 const enum hrtimer_mode mode)
172{
173 lkdtm_handler();
174 jprobe_return();
175 return 0;
176}
177
178static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd)
179{
180 lkdtm_handler();
181 jprobe_return();
182 return 0;
183}
184
185#ifdef CONFIG_IDE
186int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file,
187 struct block_device *bdev, unsigned int cmd,
188 unsigned long arg)
189{
190 lkdtm_handler();
191 jprobe_return();
192 return 0;
193}
194#endif
195
196static int lkdtm_parse_commandline(void)
197{
198 int i;
199
200 if (cpoint_name == NULL || cpoint_type == NULL ||
201 cpoint_count < 1 || recur_count < 1)
202 return -EINVAL;
203
204 for (i = 0; i < NUM_CPOINTS; ++i) {
205 if (!strcmp(cpoint_name, cp_name[i])) {
206 cpoint = i + 1;
207 break;
208 }
209 }
210
211 for (i = 0; i < NUM_CPOINT_TYPES; ++i) {
212 if (!strcmp(cpoint_type, cp_type[i])) {
213 cptype = i + 1;
214 break;
215 }
216 }
217
218 if (cpoint == INVALID || cptype == NONE)
219 return -EINVAL;
220
221 count = cpoint_count;
222
223 return 0;
224}
225
226static int recursive_loop(int a)
227{
228 char buf[1024];
229
230 memset(buf,0xFF,1024);
231 recur_count--;
232 if (!recur_count)
233 return 0;
234 else
235 return recursive_loop(a);
236}
237
238void lkdtm_handler(void)
239{
240 printk(KERN_INFO "lkdtm : Crash point %s of type %s hit\n",
241 cpoint_name, cpoint_type);
242 --count;
243
244 if (count == 0) {
245 switch (cptype) {
246 case NONE:
247 break;
248 case PANIC:
249 printk(KERN_INFO "lkdtm : PANIC\n");
250 panic("dumptest");
251 break;
252 case BUG:
253 printk(KERN_INFO "lkdtm : BUG\n");
254 BUG();
255 break;
256 case EXCEPTION:
257 printk(KERN_INFO "lkdtm : EXCEPTION\n");
258 *((int *) 0) = 0;
259 break;
260 case LOOP:
261 printk(KERN_INFO "lkdtm : LOOP\n");
262 for (;;);
263 break;
264 case OVERFLOW:
265 printk(KERN_INFO "lkdtm : OVERFLOW\n");
266 (void) recursive_loop(0);
267 break;
268 default:
269 break;
270 }
271 count = cpoint_count;
272 }
273}
274
275static int __init lkdtm_module_init(void)
276{
277 int ret;
278
279 if (lkdtm_parse_commandline() == -EINVAL) {
280 printk(KERN_INFO "lkdtm : Invalid command\n");
281 return -EINVAL;
282 }
283
284 switch (cpoint) {
285 case INT_HARDWARE_ENTRY:
286 lkdtm.kp.symbol_name = "do_IRQ";
287 lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
288 break;
289 case INT_HW_IRQ_EN:
290 lkdtm.kp.symbol_name = "handle_IRQ_event";
291 lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
292 break;
293 case INT_TASKLET_ENTRY:
294 lkdtm.kp.symbol_name = "tasklet_action";
295 lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
296 break;
297 case FS_DEVRW:
298 lkdtm.kp.symbol_name = "ll_rw_block";
299 lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
300 break;
301 case MEM_SWAPOUT:
302 lkdtm.kp.symbol_name = "shrink_inactive_list";
303 lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
304 break;
305 case TIMERADD:
306 lkdtm.kp.symbol_name = "hrtimer_start";
307 lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
308 break;
309 case SCSI_DISPATCH_CMD:
310 lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
311 lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
312 break;
313 case IDE_CORE_CP:
314#ifdef CONFIG_IDE
315 lkdtm.kp.symbol_name = "generic_ide_ioctl";
316 lkdtm.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl;
317#else
318 printk(KERN_INFO "lkdtm : Crash point not available\n");
319#endif
320 break;
321 default:
322 printk(KERN_INFO "lkdtm : Invalid Crash Point\n");
323 break;
324 }
325
326 if ((ret = register_jprobe(&lkdtm)) < 0) {
327 printk(KERN_INFO "lkdtm : Couldn't register jprobe\n");
328 return ret;
329 }
330
331 printk(KERN_INFO "lkdtm : Crash point %s of type %s registered\n",
332 cpoint_name, cpoint_type);
333 return 0;
334}
335
336static void __exit lkdtm_module_exit(void)
337{
338 unregister_jprobe(&lkdtm);
339 printk(KERN_INFO "lkdtm : Crash point unregistered\n");
340}
341
342module_init(lkdtm_module_init);
343module_exit(lkdtm_module_exit);
344
345MODULE_LICENSE("GPL");
346
