*/
static struct kprobe_blackpoint kprobe_blacklist[] = {
{"preempt_schedule",},
+ {"native_get_debugreg",},
+ {"irq_entries_start",},
+ {"common_interrupt",},
{NULL} /* Terminator */
};
#define INSNS_PER_PAGE (PAGE_SIZE/(MAX_INSN_SIZE * sizeof(kprobe_opcode_t)))
struct kprobe_insn_page {
- struct hlist_node hlist;
+ struct list_head list;
kprobe_opcode_t *insns; /* Page of instruction slots */
char slot_used[INSNS_PER_PAGE];
int nused;
};
static DEFINE_MUTEX(kprobe_insn_mutex); /* Protects kprobe_insn_pages */
-static struct hlist_head kprobe_insn_pages;
+static LIST_HEAD(kprobe_insn_pages);
static int kprobe_garbage_slots;
static int collect_garbage_slots(void);
static kprobe_opcode_t __kprobes *__get_insn_slot(void)
{
struct kprobe_insn_page *kip;
- struct hlist_node *pos;
retry:
- hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) {
+ list_for_each_entry(kip, &kprobe_insn_pages, list) {
if (kip->nused < INSNS_PER_PAGE) {
int i;
for (i = 0; i < INSNS_PER_PAGE; i++) {
kfree(kip);
return NULL;
}
- INIT_HLIST_NODE(&kip->hlist);
- hlist_add_head(&kip->hlist, &kprobe_insn_pages);
+ INIT_LIST_HEAD(&kip->list);
+ list_add(&kip->list, &kprobe_insn_pages);
memset(kip->slot_used, SLOT_CLEAN, INSNS_PER_PAGE);
kip->slot_used[0] = SLOT_USED;
kip->nused = 1;
* so as not to have to set it up again the
* next time somebody inserts a probe.
*/
- hlist_del(&kip->hlist);
- if (hlist_empty(&kprobe_insn_pages)) {
- INIT_HLIST_NODE(&kip->hlist);
- hlist_add_head(&kip->hlist,
- &kprobe_insn_pages);
- } else {
+ if (!list_is_singular(&kprobe_insn_pages)) {
+ list_del(&kip->list);
module_free(NULL, kip->insns);
kfree(kip);
}
static int __kprobes collect_garbage_slots(void)
{
- struct kprobe_insn_page *kip;
- struct hlist_node *pos, *next;
- int safety;
+ struct kprobe_insn_page *kip, *next;
/* Ensure no-one is preepmted on the garbages */
- mutex_unlock(&kprobe_insn_mutex);
- safety = check_safety();
- mutex_lock(&kprobe_insn_mutex);
- if (safety != 0)
+ if (check_safety())
return -EAGAIN;
- hlist_for_each_entry_safe(kip, pos, next, &kprobe_insn_pages, hlist) {
+ list_for_each_entry_safe(kip, next, &kprobe_insn_pages, list) {
int i;
if (kip->ngarbage == 0)
continue;
void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty)
{
struct kprobe_insn_page *kip;
- struct hlist_node *pos;
mutex_lock(&kprobe_insn_mutex);
- hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) {
+ list_for_each_entry(kip, &kprobe_insn_pages, list) {
if (kip->insns <= slot &&
slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) {
int i = (slot - kip->insns) / MAX_INSN_SIZE;
if (dirty) {
kip->slot_used[i] = SLOT_DIRTY;
kip->ngarbage++;
- } else {
+ } else
collect_one_slot(kip, i);
- }
break;
}
}
return NULL;
}
+/* Arm a kprobe with text_mutex */
+static void __kprobes arm_kprobe(struct kprobe *kp)
+{
+ mutex_lock(&text_mutex);
+ arch_arm_kprobe(kp);
+ mutex_unlock(&text_mutex);
+}
+
+/* Disarm a kprobe with text_mutex */
+static void __kprobes disarm_kprobe(struct kprobe *kp)
+{
+ mutex_lock(&text_mutex);
+ arch_disarm_kprobe(kp);
+ mutex_unlock(&text_mutex);
+}
+
/*
* Aggregate handlers for multiple kprobes support - these handlers
* take care of invoking the individual kprobe handlers on p->list
struct kprobe *kp;
list_for_each_entry_rcu(kp, &p->list, list) {
- if (kp->pre_handler && !kprobe_gone(kp)) {
+ if (kp->pre_handler && likely(!kprobe_disabled(kp))) {
set_kprobe_instance(kp);
if (kp->pre_handler(kp, regs))
return 1;
struct kprobe *kp;
list_for_each_entry_rcu(kp, &p->list, list) {
- if (kp->post_handler && !kprobe_gone(kp)) {
+ if (kp->post_handler && likely(!kprobe_disabled(kp))) {
set_kprobe_instance(kp);
kp->post_handler(kp, regs, flags);
reset_kprobe_instance();
*/
static int __kprobes add_new_kprobe(struct kprobe *ap, struct kprobe *p)
{
+ BUG_ON(kprobe_gone(ap) || kprobe_gone(p));
if (p->break_handler) {
if (ap->break_handler)
return -EEXIST;
list_add_rcu(&p->list, &ap->list);
if (p->post_handler && !ap->post_handler)
ap->post_handler = aggr_post_handler;
+
+ if (kprobe_disabled(ap) && !kprobe_disabled(p)) {
+ ap->flags &= ~KPROBE_FLAG_DISABLED;
+ if (!kprobes_all_disarmed)
+ /* Arm the breakpoint again. */
+ arm_kprobe(ap);
+ }
return 0;
}
* freed by unregister_kprobe.
*/
return ret;
- /* Clear gone flag to prevent allocating new slot again. */
- ap->flags &= ~KPROBE_FLAG_GONE;
+
/*
- * If the old_p has gone, its breakpoint has been disarmed.
- * We have to arm it again after preparing real kprobes.
+ * Clear gone flag to prevent allocating new slot again, and
+ * set disabled flag because it is not armed yet.
*/
- if (!kprobes_all_disarmed)
- arch_arm_kprobe(ap);
+ ap->flags = (ap->flags & ~KPROBE_FLAG_GONE)
+ | KPROBE_FLAG_DISABLED;
}
copy_kprobe(ap, p);
return add_new_kprobe(ap, p);
}
+/* Try to disable aggr_kprobe, and return 1 if succeeded.*/
+static int __kprobes try_to_disable_aggr_kprobe(struct kprobe *p)
+{
+ struct kprobe *kp;
+
+ list_for_each_entry_rcu(kp, &p->list, list) {
+ if (!kprobe_disabled(kp))
+ /*
+ * There is an active probe on the list.
+ * We can't disable aggr_kprobe.
+ */
+ return 0;
+ }
+ p->flags |= KPROBE_FLAG_DISABLED;
+ return 1;
+}
+
static int __kprobes in_kprobes_functions(unsigned long addr)
{
struct kprobe_blackpoint *kb;
return (kprobe_opcode_t *)(((char *)addr) + p->offset);
}
+/* Check passed kprobe is valid and return kprobe in kprobe_table. */
+static struct kprobe * __kprobes __get_valid_kprobe(struct kprobe *p)
+{
+ struct kprobe *old_p, *list_p;
+
+ old_p = get_kprobe(p->addr);
+ if (unlikely(!old_p))
+ return NULL;
+
+ if (p != old_p) {
+ list_for_each_entry_rcu(list_p, &old_p->list, list)
+ if (list_p == p)
+ /* kprobe p is a valid probe */
+ goto valid;
+ return NULL;
+ }
+valid:
+ return old_p;
+}
+
+/* Return error if the kprobe is being re-registered */
+static inline int check_kprobe_rereg(struct kprobe *p)
+{
+ int ret = 0;
+ struct kprobe *old_p;
+
+ mutex_lock(&kprobe_mutex);
+ old_p = __get_valid_kprobe(p);
+ if (old_p)
+ ret = -EINVAL;
+ mutex_unlock(&kprobe_mutex);
+ return ret;
+}
+
int __kprobes register_kprobe(struct kprobe *p)
{
int ret = 0;
return -EINVAL;
p->addr = addr;
+ ret = check_kprobe_rereg(p);
+ if (ret)
+ return ret;
+
preempt_disable();
- if (!__kernel_text_address((unsigned long) p->addr) ||
+ if (!kernel_text_address((unsigned long) p->addr) ||
in_kprobes_functions((unsigned long) p->addr)) {
preempt_enable();
return -EINVAL;
}
- p->flags = 0;
+ /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
+ p->flags &= KPROBE_FLAG_DISABLED;
+
/*
* Check if are we probing a module.
*/
hlist_add_head_rcu(&p->hlist,
&kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]);
- if (!kprobes_all_disarmed)
+ if (!kprobes_all_disarmed && !kprobe_disabled(p))
arch_arm_kprobe(p);
out_unlock_text:
{
struct kprobe *old_p, *list_p;
- old_p = get_kprobe(p->addr);
- if (unlikely(!old_p))
+ old_p = __get_valid_kprobe(p);
+ if (old_p == NULL)
return -EINVAL;
- if (p != old_p) {
- list_for_each_entry_rcu(list_p, &old_p->list, list)
- if (list_p == p)
- /* kprobe p is a valid probe */
- goto valid_p;
- return -EINVAL;
- }
-valid_p:
if (old_p == p ||
(old_p->pre_handler == aggr_pre_handler &&
list_is_singular(&old_p->list))) {
* enabled and not gone - otherwise, the breakpoint would
* already have been removed. We save on flushing icache.
*/
- if (!kprobes_all_disarmed && !kprobe_gone(old_p)) {
- mutex_lock(&text_mutex);
- arch_disarm_kprobe(p);
- mutex_unlock(&text_mutex);
- }
+ if (!kprobes_all_disarmed && !kprobe_disabled(old_p))
+ disarm_kprobe(p);
hlist_del_rcu(&old_p->hlist);
} else {
if (p->break_handler && !kprobe_gone(p))
}
noclean:
list_del_rcu(&p->list);
+ if (!kprobe_disabled(old_p)) {
+ try_to_disable_aggr_kprobe(old_p);
+ if (!kprobes_all_disarmed && kprobe_disabled(old_p))
+ disarm_kprobe(old_p);
+ }
}
return 0;
}
/* Pre-allocate memory for max kretprobe instances */
if (rp->maxactive <= 0) {
#ifdef CONFIG_PREEMPT
- rp->maxactive = max(10, 2 * NR_CPUS);
+ rp->maxactive = max_t(unsigned int, 10, 2*num_possible_cpus());
#else
- rp->maxactive = NR_CPUS;
+ rp->maxactive = num_possible_cpus();
#endif
}
spin_lock_init(&rp->lock);
static void __kprobes kill_kprobe(struct kprobe *p)
{
struct kprobe *kp;
+
p->flags |= KPROBE_FLAG_GONE;
if (p->pre_handler == aggr_pre_handler) {
/*
arch_remove_kprobe(p);
}
+void __kprobes dump_kprobe(struct kprobe *kp)
+{
+ printk(KERN_WARNING "Dumping kprobe:\n");
+ printk(KERN_WARNING "Name: %s\nAddress: %p\nOffset: %x\n",
+ kp->symbol_name, kp->addr, kp->offset);
+}
+
/* Module notifier call back, checking kprobes on the module */
static int __kprobes kprobes_module_callback(struct notifier_block *nb,
unsigned long val, void *data)
else
kprobe_type = "k";
if (sym)
- seq_printf(pi, "%p %s %s+0x%x %s %s\n", p->addr, kprobe_type,
- sym, offset, (modname ? modname : " "),
- (kprobe_gone(p) ? "[GONE]" : ""));
+ seq_printf(pi, "%p %s %s+0x%x %s %s%s\n",
+ p->addr, kprobe_type, sym, offset,
+ (modname ? modname : " "),
+ (kprobe_gone(p) ? "[GONE]" : ""),
+ ((kprobe_disabled(p) && !kprobe_gone(p)) ?
+ "[DISABLED]" : ""));
else
- seq_printf(pi, "%p %s %p %s\n", p->addr, kprobe_type, p->addr,
- (kprobe_gone(p) ? "[GONE]" : ""));
+ seq_printf(pi, "%p %s %p %s%s\n",
+ p->addr, kprobe_type, p->addr,
+ (kprobe_gone(p) ? "[GONE]" : ""),
+ ((kprobe_disabled(p) && !kprobe_gone(p)) ?
+ "[DISABLED]" : ""));
}
static void __kprobes *kprobe_seq_start(struct seq_file *f, loff_t *pos)
return 0;
}
-static struct seq_operations kprobes_seq_ops = {
+static const struct seq_operations kprobes_seq_ops = {
.start = kprobe_seq_start,
.next = kprobe_seq_next,
.stop = kprobe_seq_stop,
return seq_open(filp, &kprobes_seq_ops);
}
-static struct file_operations debugfs_kprobes_operations = {
+static const struct file_operations debugfs_kprobes_operations = {
.open = kprobes_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
+/* Disable one kprobe */
+int __kprobes disable_kprobe(struct kprobe *kp)
+{
+ int ret = 0;
+ struct kprobe *p;
+
+ mutex_lock(&kprobe_mutex);
+
+ /* Check whether specified probe is valid. */
+ p = __get_valid_kprobe(kp);
+ if (unlikely(p == NULL)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* If the probe is already disabled (or gone), just return */
+ if (kprobe_disabled(kp))
+ goto out;
+
+ kp->flags |= KPROBE_FLAG_DISABLED;
+ if (p != kp)
+ /* When kp != p, p is always enabled. */
+ try_to_disable_aggr_kprobe(p);
+
+ if (!kprobes_all_disarmed && kprobe_disabled(p))
+ disarm_kprobe(p);
+out:
+ mutex_unlock(&kprobe_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(disable_kprobe);
+
+/* Enable one kprobe */
+int __kprobes enable_kprobe(struct kprobe *kp)
+{
+ int ret = 0;
+ struct kprobe *p;
+
+ mutex_lock(&kprobe_mutex);
+
+ /* Check whether specified probe is valid. */
+ p = __get_valid_kprobe(kp);
+ if (unlikely(p == NULL)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (kprobe_gone(kp)) {
+ /* This kprobe has gone, we couldn't enable it. */
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (!kprobes_all_disarmed && kprobe_disabled(p))
+ arm_kprobe(p);
+
+ p->flags &= ~KPROBE_FLAG_DISABLED;
+ if (p != kp)
+ kp->flags &= ~KPROBE_FLAG_DISABLED;
+out:
+ mutex_unlock(&kprobe_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(enable_kprobe);
+
static void __kprobes arm_all_kprobes(void)
{
struct hlist_head *head;
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry_rcu(p, node, head, hlist)
- if (!kprobe_gone(p))
+ if (!kprobe_disabled(p))
arch_arm_kprobe(p);
}
mutex_unlock(&text_mutex);
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry_rcu(p, node, head, hlist) {
- if (!arch_trampoline_kprobe(p) && !kprobe_gone(p))
+ if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p))
arch_disarm_kprobe(p);
}
}
return count;
}
-static struct file_operations fops_kp = {
+static const struct file_operations fops_kp = {
.read = read_enabled_file_bool,
.write = write_enabled_file_bool,
};
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff