static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
-static atomic_t kprobe_count;
/* NOTE: change this value only with kprobe_mutex held */
static bool kprobe_enabled;
DEFINE_SPINLOCK(kretprobe_lock); /* Protects kretprobe_inst_table */
static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
-static struct notifier_block kprobe_page_fault_nb = {
- .notifier_call = kprobe_exceptions_notify,
- .priority = 0x7fffffff /* we need to notified first */
-};
-
#ifdef __ARCH_WANT_KPROBES_INSN_SLOT
/*
* kprobe->ainsn.insn points to the copy of the instruction to be
return 0;
}
+/*
+ * If we have a symbol_name argument, look it up and add the offset field
+ * to it. This way, we can specify a relative address to a symbol.
+ */
+static kprobe_opcode_t __kprobes *kprobe_addr(struct kprobe *p)
+{
+ kprobe_opcode_t *addr = p->addr;
+ if (p->symbol_name) {
+ if (addr)
+ return NULL;
+ kprobe_lookup_name(p->symbol_name, addr);
+ }
+
+ if (!addr)
+ return NULL;
+ return (kprobe_opcode_t *)(((char *)addr) + p->offset);
+}
+
static int __kprobes __register_kprobe(struct kprobe *p,
unsigned long called_from)
{
int ret = 0;
struct kprobe *old_p;
struct module *probed_mod;
+ kprobe_opcode_t *addr;
- /*
- * If we have a symbol_name argument look it up,
- * and add it to the address. That way the addr
- * field can either be global or relative to a symbol.
- */
- if (p->symbol_name) {
- if (p->addr)
- return -EINVAL;
- kprobe_lookup_name(p->symbol_name, p->addr);
- }
-
- if (!p->addr)
+ addr = kprobe_addr(p);
+ if (!addr)
return -EINVAL;
- p->addr = (kprobe_opcode_t *)(((char *)p->addr)+ p->offset);
+ p->addr = addr;
if (!kernel_text_address((unsigned long) p->addr) ||
in_kprobes_functions((unsigned long) p->addr))
old_p = get_kprobe(p->addr);
if (old_p) {
ret = register_aggr_kprobe(old_p, p);
- if (!ret)
- atomic_inc(&kprobe_count);
goto out;
}
hlist_add_head_rcu(&p->hlist,
&kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]);
- if (kprobe_enabled) {
- if (atomic_add_return(1, &kprobe_count) == \
- (ARCH_INACTIVE_KPROBE_COUNT + 1))
- register_page_fault_notifier(&kprobe_page_fault_nb);
-
+ if (kprobe_enabled)
arch_arm_kprobe(p);
- }
+
out:
mutex_unlock(&kprobe_mutex);
}
mutex_unlock(&kprobe_mutex);
}
-
- /* Call unregister_page_fault_notifier()
- * if no probes are active
- */
- mutex_lock(&kprobe_mutex);
- if (atomic_add_return(-1, &kprobe_count) == \
- ARCH_INACTIVE_KPROBE_COUNT)
- unregister_page_fault_notifier(&kprobe_page_fault_nb);
- mutex_unlock(&kprobe_mutex);
- return;
}
static struct notifier_block kprobe_exceptions_nb = {
unregister_kprobe(&jp->kp);
}
-#ifdef ARCH_SUPPORTS_KRETPROBES
-
+#ifdef CONFIG_KRETPROBES
/*
* This kprobe pre_handler is registered with every kretprobe. When probe
* hits it will set up the return probe.
struct kretprobe_instance, uflist);
ri->rp = rp;
ri->task = current;
+
+ if (rp->entry_handler && rp->entry_handler(ri, regs)) {
+ spin_unlock_irqrestore(&kretprobe_lock, flags);
+ return 0;
+ }
+
arch_prepare_kretprobe(ri, regs);
/* XXX(hch): why is there no hlist_move_head? */
int ret = 0;
struct kretprobe_instance *inst;
int i;
+ void *addr;
+
+ if (kretprobe_blacklist_size) {
+ addr = kprobe_addr(&rp->kp);
+ if (!addr)
+ return -EINVAL;
+
+ for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
+ if (kretprobe_blacklist[i].addr == addr)
+ return -EINVAL;
+ }
+ }
rp->kp.pre_handler = pre_handler_kretprobe;
rp->kp.post_handler = NULL;
INIT_HLIST_HEAD(&rp->used_instances);
INIT_HLIST_HEAD(&rp->free_instances);
for (i = 0; i < rp->maxactive; i++) {
- inst = kmalloc(sizeof(struct kretprobe_instance), GFP_KERNEL);
+ inst = kmalloc(sizeof(struct kretprobe_instance) +
+ rp->data_size, GFP_KERNEL);
if (inst == NULL) {
free_rp_inst(rp);
return -ENOMEM;
return ret;
}
-#else /* ARCH_SUPPORTS_KRETPROBES */
-
+#else /* CONFIG_KRETPROBES */
int __kprobes register_kretprobe(struct kretprobe *rp)
{
return -ENOSYS;
{
return 0;
}
-
-#endif /* ARCH_SUPPORTS_KRETPROBES */
+#endif /* CONFIG_KRETPROBES */
void __kprobes unregister_kretprobe(struct kretprobe *rp)
{
INIT_HLIST_HEAD(&kprobe_table[i]);
INIT_HLIST_HEAD(&kretprobe_inst_table[i]);
}
- atomic_set(&kprobe_count, 0);
+
+ if (kretprobe_blacklist_size) {
+ /* lookup the function address from its name */
+ for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
+ kprobe_lookup_name(kretprobe_blacklist[i].name,
+ kretprobe_blacklist[i].addr);
+ if (!kretprobe_blacklist[i].addr)
+ printk("kretprobe: lookup failed: %s\n",
+ kretprobe_blacklist[i].name);
+ }
+ }
/* By default, kprobes are enabled */
kprobe_enabled = true;
if (!err)
err = register_die_notifier(&kprobe_exceptions_nb);
+ if (!err)
+ init_test_probes();
return err;
}
if (kprobe_enabled)
goto already_enabled;
- /*
- * Re-register the page fault notifier only if there are any
- * active probes at the time of enabling kprobes globally
- */
- if (atomic_read(&kprobe_count) > ARCH_INACTIVE_KPROBE_COUNT)
- register_page_fault_notifier(&kprobe_page_fault_nb);
-
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry_rcu(p, node, head, hlist)
mutex_unlock(&kprobe_mutex);
/* Allow all currently running kprobes to complete */
synchronize_sched();
-
- mutex_lock(&kprobe_mutex);
- /* Unconditionally unregister the page_fault notifier */
- unregister_page_fault_notifier(&kprobe_page_fault_nb);
+ return;
already_disabled:
mutex_unlock(&kprobe_mutex);
git.samba.org / sfrench / cifs-2.6.git / blobdiff