aboutsummaryrefslogtreecommitdiff
path: root/drivers/misc/lkdtm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/misc/lkdtm.c')
-rw-r--r--drivers/misc/lkdtm.c472
1 files changed, 390 insertions, 82 deletions
diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
index 3648b23d5c9..4a0648301fd 100644
--- a/drivers/misc/lkdtm.c
+++ b/drivers/misc/lkdtm.c
@@ -26,21 +26,9 @@
* It is adapted from the Linux Kernel Dump Test Tool by
* Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
*
- * Usage : insmod lkdtm.ko [recur_count={>0}] cpoint_name=<> cpoint_type=<>
- * [cpoint_count={>0}]
+ * Debugfs support added by Simon Kagstrom <simon.kagstrom@netinsight.net>
*
- * recur_count : Recursion level for the stack overflow test. Default is 10.
- *
- * cpoint_name : Crash point where the kernel is to be crashed. It can be
- * one of INT_HARDWARE_ENTRY, INT_HW_IRQ_EN, INT_TASKLET_ENTRY,
- * FS_DEVRW, MEM_SWAPOUT, TIMERADD, SCSI_DISPATCH_CMD,
- * IDE_CORE_CP
- *
- * cpoint_type : Indicates the action to be taken on hitting the crash point.
- * It can be one of PANIC, BUG, EXCEPTION, LOOP, OVERFLOW
- *
- * cpoint_count : Indicates the number of times the crash point is to be hit
- * to trigger an action. The default is 10.
+ * See Documentation/fault-injection/provoke-crashes.txt for instructions
*/
#include <linux/kernel.h>
@@ -53,13 +41,12 @@
#include <linux/interrupt.h>
#include <linux/hrtimer.h>
#include <scsi/scsi_cmnd.h>
+#include <linux/debugfs.h>
#ifdef CONFIG_IDE
#include <linux/ide.h>
#endif
-#define NUM_CPOINTS 8
-#define NUM_CPOINT_TYPES 5
#define DEFAULT_COUNT 10
#define REC_NUM_DEFAULT 10
@@ -72,7 +59,8 @@ enum cname {
MEM_SWAPOUT,
TIMERADD,
SCSI_DISPATCH_CMD,
- IDE_CORE_CP
+ IDE_CORE_CP,
+ DIRECT,
};
enum ctype {
@@ -81,7 +69,11 @@ enum ctype {
BUG,
EXCEPTION,
LOOP,
- OVERFLOW
+ OVERFLOW,
+ CORRUPT_STACK,
+ UNALIGNED_LOAD_STORE_WRITE,
+ OVERWRITE_ALLOCATION,
+ WRITE_AFTER_FREE,
};
static char* cp_name[] = {
@@ -92,7 +84,8 @@ static char* cp_name[] = {
"MEM_SWAPOUT",
"TIMERADD",
"SCSI_DISPATCH_CMD",
- "IDE_CORE_CP"
+ "IDE_CORE_CP",
+ "DIRECT",
};
static char* cp_type[] = {
@@ -100,7 +93,11 @@ static char* cp_type[] = {
"BUG",
"EXCEPTION",
"LOOP",
- "OVERFLOW"
+ "OVERFLOW",
+ "CORRUPT_STACK",
+ "UNALIGNED_LOAD_STORE_WRITE",
+ "OVERWRITE_ALLOCATION",
+ "WRITE_AFTER_FREE",
};
static struct jprobe lkdtm;
@@ -193,34 +190,66 @@ int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file,
}
#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 NONE;
+}
+
+static const char *cp_type_to_str(enum ctype type)
+{
+ if (type == 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 == INVALID || name < 0 || name > ARRAY_SIZE(cp_name))
+ return "INVALID";
+
+ return cp_name[name - 1];
+}
+
+
static int lkdtm_parse_commandline(void)
{
int i;
- if (cpoint_name == NULL || cpoint_type == NULL ||
- cpoint_count < 1 || recur_count < 1)
+ if (cpoint_count < 1 || recur_count < 1)
return -EINVAL;
- for (i = 0; i < NUM_CPOINTS; ++i) {
+ count = cpoint_count;
+
+ /* 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 == NONE)
+ return -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(cp_name); i++) {
if (!strcmp(cpoint_name, cp_name[i])) {
cpoint = i + 1;
- break;
- }
- }
-
- for (i = 0; i < NUM_CPOINT_TYPES; ++i) {
- if (!strcmp(cpoint_type, cp_type[i])) {
- cptype = i + 1;
- break;
+ return 0;
}
}
- if (cpoint == INVALID || cptype == NONE)
- return -EINVAL;
-
- count = cpoint_count;
-
- return 0;
+ /* Could not find a valid crash point */
+ return -EINVAL;
}
static int recursive_loop(int a)
@@ -235,53 +264,92 @@ static int recursive_loop(int a)
return recursive_loop(a);
}
-void lkdtm_handler(void)
+static void lkdtm_do_action(enum ctype which)
{
- printk(KERN_INFO "lkdtm : Crash point %s of type %s hit\n",
- cpoint_name, cpoint_type);
- --count;
+ switch (which) {
+ case PANIC:
+ panic("dumptest");
+ break;
+ case BUG:
+ BUG();
+ break;
+ case EXCEPTION:
+ *((int *) 0) = 0;
+ break;
+ case LOOP:
+ for (;;)
+ ;
+ break;
+ case OVERFLOW:
+ (void) recursive_loop(0);
+ break;
+ case CORRUPT_STACK: {
+ volatile u32 data[8];
+ volatile u32 *p = data;
+
+ p[12] = 0x12345678;
+ break;
+ }
+ case 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 OVERWRITE_ALLOCATION: {
+ size_t len = 1020;
+ u32 *data = kmalloc(len, GFP_KERNEL);
+
+ data[1024 / sizeof(u32)] = 0x12345678;
+ kfree(data);
+ break;
+ }
+ case WRITE_AFTER_FREE: {
+ size_t len = 1024;
+ u32 *data = kmalloc(len, GFP_KERNEL);
+
+ kfree(data);
+ schedule();
+ memset(data, 0x78, len);
+ break;
+ }
+ case NONE:
+ default:
+ break;
+ }
+
+}
+
+static void lkdtm_handler(void)
+{
+ 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) {
- switch (cptype) {
- case NONE:
- break;
- case PANIC:
- printk(KERN_INFO "lkdtm : PANIC\n");
- panic("dumptest");
- break;
- case BUG:
- printk(KERN_INFO "lkdtm : BUG\n");
- BUG();
- break;
- case EXCEPTION:
- printk(KERN_INFO "lkdtm : EXCEPTION\n");
- *((int *) 0) = 0;
- break;
- case LOOP:
- printk(KERN_INFO "lkdtm : LOOP\n");
- for (;;);
- break;
- case OVERFLOW:
- printk(KERN_INFO "lkdtm : OVERFLOW\n");
- (void) recursive_loop(0);
- break;
- default:
- break;
- }
+ lkdtm_do_action(cptype);
count = cpoint_count;
}
}
-static int __init lkdtm_module_init(void)
+static int lkdtm_register_cpoint(enum cname which)
{
int ret;
- if (lkdtm_parse_commandline() == -EINVAL) {
- printk(KERN_INFO "lkdtm : Invalid command\n");
- return -EINVAL;
- }
+ cpoint = INVALID;
+ if (lkdtm.entry != NULL)
+ unregister_jprobe(&lkdtm);
- switch (cpoint) {
+ switch (which) {
+ case DIRECT:
+ lkdtm_do_action(cptype);
+ return 0;
case INT_HARDWARE_ENTRY:
lkdtm.kp.symbol_name = "do_IRQ";
lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
@@ -315,28 +383,268 @@ static int __init lkdtm_module_init(void)
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");
+ printk(KERN_INFO "lkdtm: Crash point not available\n");
+ return -EINVAL;
#endif
break;
default:
- printk(KERN_INFO "lkdtm : Invalid Crash Point\n");
- break;
+ 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");
- return ret;
+ printk(KERN_INFO "lkdtm: Couldn't register jprobe\n");
+ cpoint = 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 == 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(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(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(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(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(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(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(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(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 == 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,
+ .open = lkdtm_debugfs_open,
+ .write = direct_entry} },
+ {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = int_hardware_entry} },
+ {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = int_hw_irq_en} },
+ {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = int_tasklet_entry} },
+ {"FS_DEVRW", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = fs_devrw_entry} },
+ {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = mem_swapout_entry} },
+ {"TIMERADD", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = timeradd_entry} },
+ {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read,
+ .open = lkdtm_debugfs_open,
+ .write = scsi_dispatch_cmd_entry} },
+ {"IDE_CORE_CP", {.read = lkdtm_debugfs_read,
+ .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 != INVALID && cptype != 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");
}
- printk(KERN_INFO "lkdtm : Crash point %s of type %s registered\n",
- cpoint_name, cpoint_type);
return 0;
+
+out_err:
+ debugfs_remove_recursive(lkdtm_debugfs_root);
+ return ret;
}
static void __exit lkdtm_module_exit(void)
{
- unregister_jprobe(&lkdtm);
- printk(KERN_INFO "lkdtm : Crash point unregistered\n");
+ debugfs_remove_recursive(lkdtm_debugfs_root);
+
+ unregister_jprobe(&lkdtm);
+ printk(KERN_INFO "lkdtm: Crash point unregistered\n");
}
module_init(lkdtm_module_init);
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-15 13:42:15 +0000