X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Fkprobes.c;h=a5e74ddee0e2f3a9937e46e95eae61e9b44b8746;hb=d1ec64409bf6fed877d0e55e23587b2b6f5d7d58;hp=a1e233a19586e39386d8ab89d4b68cc788863bb2;hpb=017c39bdb1b3ac1da6db339474a77b528043c05a;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/kprobes.c b/kernel/kprobes.c index a1e233a..a5e74dd 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #include @@ -67,7 +68,7 @@ static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE]; static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE]; /* NOTE: change this value only with kprobe_mutex held */ -static bool kprobe_enabled; +static bool kprobes_all_disarmed; static DEFINE_MUTEX(kprobe_mutex); /* Protects kprobe_table */ static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL; @@ -123,7 +124,7 @@ static int collect_garbage_slots(void); static int __kprobes check_safety(void) { int ret = 0; -#if defined(CONFIG_PREEMPT) && defined(CONFIG_PM) +#if defined(CONFIG_PREEMPT) && defined(CONFIG_FREEZER) ret = freeze_processes(); if (ret == 0) { struct task_struct *p, *q; @@ -327,7 +328,7 @@ static int __kprobes aggr_pre_handler(struct kprobe *p, struct pt_regs *regs) struct kprobe *kp; list_for_each_entry_rcu(kp, &p->list, list) { - if (kp->pre_handler) { + if (kp->pre_handler && likely(!kprobe_disabled(kp))) { set_kprobe_instance(kp); if (kp->pre_handler(kp, regs)) return 1; @@ -343,7 +344,7 @@ static void __kprobes aggr_post_handler(struct kprobe *p, struct pt_regs *regs, struct kprobe *kp; list_for_each_entry_rcu(kp, &p->list, list) { - if (kp->post_handler) { + if (kp->post_handler && likely(!kprobe_disabled(kp))) { set_kprobe_instance(kp); kp->post_handler(kp, regs, flags); reset_kprobe_instance(); @@ -517,20 +518,28 @@ static inline void copy_kprobe(struct kprobe *old_p, struct kprobe *p) } /* -* Add the new probe to old_p->list. Fail if this is the +* Add the new probe to ap->list. Fail if this is the * second jprobe at the address - two jprobes can't coexist */ -static int __kprobes add_new_kprobe(struct kprobe *old_p, struct kprobe *p) +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 (old_p->break_handler) + if (ap->break_handler) return -EEXIST; - list_add_tail_rcu(&p->list, &old_p->list); - old_p->break_handler = aggr_break_handler; + list_add_tail_rcu(&p->list, &ap->list); + ap->break_handler = aggr_break_handler; } else - list_add_rcu(&p->list, &old_p->list); - if (p->post_handler && !old_p->post_handler) - old_p->post_handler = aggr_post_handler; + 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. */ + arch_arm_kprobe(ap); + } return 0; } @@ -543,11 +552,13 @@ static inline void add_aggr_kprobe(struct kprobe *ap, struct kprobe *p) copy_kprobe(p, ap); flush_insn_slot(ap); ap->addr = p->addr; + ap->flags = p->flags; ap->pre_handler = aggr_pre_handler; ap->fault_handler = aggr_fault_handler; - if (p->post_handler) + /* We don't care the kprobe which has gone. */ + if (p->post_handler && !kprobe_gone(p)) ap->post_handler = aggr_post_handler; - if (p->break_handler) + if (p->break_handler && !kprobe_gone(p)) ap->break_handler = aggr_break_handler; INIT_LIST_HEAD(&ap->list); @@ -564,20 +575,59 @@ static int __kprobes register_aggr_kprobe(struct kprobe *old_p, struct kprobe *p) { int ret = 0; - struct kprobe *ap; + struct kprobe *ap = old_p; - if (old_p->pre_handler == aggr_pre_handler) { - copy_kprobe(old_p, p); - ret = add_new_kprobe(old_p, p); - } else { + if (old_p->pre_handler != aggr_pre_handler) { + /* If old_p is not an aggr_probe, create new aggr_kprobe. */ ap = kzalloc(sizeof(struct kprobe), GFP_KERNEL); if (!ap) return -ENOMEM; add_aggr_kprobe(ap, old_p); - copy_kprobe(ap, p); - ret = add_new_kprobe(ap, p); } - return ret; + + if (kprobe_gone(ap)) { + /* + * Attempting to insert new probe at the same location that + * had a probe in the module vaddr area which already + * freed. So, the instruction slot has already been + * released. We need a new slot for the new probe. + */ + ret = arch_prepare_kprobe(ap); + if (ret) + /* + * Even if fail to allocate new slot, don't need to + * free aggr_probe. It will be used next time, or + * freed by unregister_kprobe. + */ + return ret; + + /* + * Clear gone flag to prevent allocating new slot again, and + * set disabled flag because it is not armed yet. + */ + 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) @@ -619,8 +669,7 @@ static kprobe_opcode_t __kprobes *kprobe_addr(struct kprobe *p) return (kprobe_opcode_t *)(((char *)addr) + p->offset); } -static int __kprobes __register_kprobe(struct kprobe *p, - unsigned long called_from) +int __kprobes register_kprobe(struct kprobe *p) { int ret = 0; struct kprobe *old_p; @@ -639,28 +688,32 @@ static int __kprobes __register_kprobe(struct kprobe *p, return -EINVAL; } - p->mod_refcounted = 0; + /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */ + p->flags &= KPROBE_FLAG_DISABLED; /* * Check if are we probing a module. */ probed_mod = __module_text_address((unsigned long) p->addr); if (probed_mod) { - struct module *calling_mod; - calling_mod = __module_text_address(called_from); /* - * We must allow modules to probe themself and in this case - * avoid incrementing the module refcount, so as to allow - * unloading of self probing modules. + * We must hold a refcount of the probed module while updating + * its code to prohibit unexpected unloading. */ - if (calling_mod != probed_mod) { - if (unlikely(!try_module_get(probed_mod))) { - preempt_enable(); - return -EINVAL; - } - p->mod_refcounted = 1; - } else - probed_mod = NULL; + if (unlikely(!try_module_get(probed_mod))) { + preempt_enable(); + return -EINVAL; + } + /* + * If the module freed .init.text, we couldn't insert + * kprobes in there. + */ + if (within_module_init((unsigned long)p->addr, probed_mod) && + probed_mod->state != MODULE_STATE_COMING) { + module_put(probed_mod); + preempt_enable(); + return -EINVAL; + } } preempt_enable(); @@ -673,59 +726,79 @@ static int __kprobes __register_kprobe(struct kprobe *p, goto out; } + mutex_lock(&text_mutex); ret = arch_prepare_kprobe(p); if (ret) - goto out; + goto out_unlock_text; INIT_HLIST_NODE(&p->hlist); hlist_add_head_rcu(&p->hlist, &kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]); - if (kprobe_enabled) + if (!kprobes_all_disarmed && !kprobe_disabled(p)) arch_arm_kprobe(p); +out_unlock_text: + mutex_unlock(&text_mutex); out: mutex_unlock(&kprobe_mutex); - if (ret && probed_mod) + if (probed_mod) module_put(probed_mod); + return ret; } +EXPORT_SYMBOL_GPL(register_kprobe); -/* - * Unregister a kprobe without a scheduler synchronization. - */ -static int __kprobes __unregister_kprobe_top(struct kprobe *p) +/* 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 -EINVAL; + 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_p; - return -EINVAL; + goto valid; + return NULL; } -valid_p: +valid: + return old_p; +} + +/* + * Unregister a kprobe without a scheduler synchronization. + */ +static int __kprobes __unregister_kprobe_top(struct kprobe *p) +{ + struct kprobe *old_p, *list_p; + + old_p = __get_valid_kprobe(p); + if (old_p == NULL) + return -EINVAL; + if (old_p == p || (old_p->pre_handler == aggr_pre_handler && list_is_singular(&old_p->list))) { /* * Only probe on the hash list. Disarm only if kprobes are - * enabled - otherwise, the breakpoint would already have - * been removed. We save on flushing icache. + * enabled and not gone - otherwise, the breakpoint would + * already have been removed. We save on flushing icache. */ - if (kprobe_enabled) + if (!kprobes_all_disarmed && !kprobe_disabled(old_p)) { + mutex_lock(&text_mutex); arch_disarm_kprobe(p); + mutex_unlock(&text_mutex); + } hlist_del_rcu(&old_p->hlist); } else { - if (p->break_handler) + if (p->break_handler && !kprobe_gone(p)) old_p->break_handler = NULL; - if (p->post_handler) { + if (p->post_handler && !kprobe_gone(p)) { list_for_each_entry_rcu(list_p, &old_p->list, list) { if ((list_p != p) && (list_p->post_handler)) goto noclean; @@ -734,45 +807,38 @@ valid_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)) + arch_disarm_kprobe(old_p); + } } return 0; } static void __kprobes __unregister_kprobe_bottom(struct kprobe *p) { - struct module *mod; struct kprobe *old_p; - if (p->mod_refcounted) { - /* - * Since we've already incremented refcount, - * we don't need to disable preemption. - */ - mod = module_text_address((unsigned long)p->addr); - if (mod) - module_put(mod); - } - - if (list_empty(&p->list) || list_is_singular(&p->list)) { - if (!list_empty(&p->list)) { - /* "p" is the last child of an aggr_kprobe */ - old_p = list_entry(p->list.next, struct kprobe, list); - list_del(&p->list); - kfree(old_p); - } + if (list_empty(&p->list)) arch_remove_kprobe(p); + else if (list_is_singular(&p->list)) { + /* "p" is the last child of an aggr_kprobe */ + old_p = list_entry(p->list.next, struct kprobe, list); + list_del(&p->list); + arch_remove_kprobe(old_p); + kfree(old_p); } } -static int __kprobes __register_kprobes(struct kprobe **kps, int num, - unsigned long called_from) +int __kprobes register_kprobes(struct kprobe **kps, int num) { int i, ret = 0; if (num <= 0) return -EINVAL; for (i = 0; i < num; i++) { - ret = __register_kprobe(kps[i], called_from); + ret = register_kprobe(kps[i]); if (ret < 0) { if (i > 0) unregister_kprobes(kps, i); @@ -781,26 +847,13 @@ static int __kprobes __register_kprobes(struct kprobe **kps, int num, } return ret; } - -/* - * Registration and unregistration functions for kprobe. - */ -int __kprobes register_kprobe(struct kprobe *p) -{ - return __register_kprobes(&p, 1, - (unsigned long)__builtin_return_address(0)); -} +EXPORT_SYMBOL_GPL(register_kprobes); void __kprobes unregister_kprobe(struct kprobe *p) { unregister_kprobes(&p, 1); } - -int __kprobes register_kprobes(struct kprobe **kps, int num) -{ - return __register_kprobes(kps, num, - (unsigned long)__builtin_return_address(0)); -} +EXPORT_SYMBOL_GPL(unregister_kprobe); void __kprobes unregister_kprobes(struct kprobe **kps, int num) { @@ -819,6 +872,7 @@ void __kprobes unregister_kprobes(struct kprobe **kps, int num) if (kps[i]->addr) __unregister_kprobe_bottom(kps[i]); } +EXPORT_SYMBOL_GPL(unregister_kprobes); static struct notifier_block kprobe_exceptions_nb = { .notifier_call = kprobe_exceptions_notify, @@ -830,8 +884,7 @@ unsigned long __weak arch_deref_entry_point(void *entry) return (unsigned long)entry; } -static int __kprobes __register_jprobes(struct jprobe **jps, int num, - unsigned long called_from) +int __kprobes register_jprobes(struct jprobe **jps, int num) { struct jprobe *jp; int ret = 0, i; @@ -849,7 +902,7 @@ static int __kprobes __register_jprobes(struct jprobe **jps, int num, /* Todo: Verify probepoint is a function entry point */ jp->kp.pre_handler = setjmp_pre_handler; jp->kp.break_handler = longjmp_break_handler; - ret = __register_kprobe(&jp->kp, called_from); + ret = register_kprobe(&jp->kp); } if (ret < 0) { if (i > 0) @@ -859,23 +912,19 @@ static int __kprobes __register_jprobes(struct jprobe **jps, int num, } return ret; } +EXPORT_SYMBOL_GPL(register_jprobes); int __kprobes register_jprobe(struct jprobe *jp) { - return __register_jprobes(&jp, 1, - (unsigned long)__builtin_return_address(0)); + return register_jprobes(&jp, 1); } +EXPORT_SYMBOL_GPL(register_jprobe); void __kprobes unregister_jprobe(struct jprobe *jp) { unregister_jprobes(&jp, 1); } - -int __kprobes register_jprobes(struct jprobe **jps, int num) -{ - return __register_jprobes(jps, num, - (unsigned long)__builtin_return_address(0)); -} +EXPORT_SYMBOL_GPL(unregister_jprobe); void __kprobes unregister_jprobes(struct jprobe **jps, int num) { @@ -895,6 +944,7 @@ void __kprobes unregister_jprobes(struct jprobe **jps, int num) __unregister_kprobe_bottom(&jps[i]->kp); } } +EXPORT_SYMBOL_GPL(unregister_jprobes); #ifdef CONFIG_KRETPROBES /* @@ -920,10 +970,8 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p, ri->rp = rp; ri->task = current; - if (rp->entry_handler && rp->entry_handler(ri, regs)) { - spin_unlock_irqrestore(&rp->lock, flags); + if (rp->entry_handler && rp->entry_handler(ri, regs)) return 0; - } arch_prepare_kretprobe(ri, regs); @@ -939,8 +987,7 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p, return 0; } -static int __kprobes __register_kretprobe(struct kretprobe *rp, - unsigned long called_from) +int __kprobes register_kretprobe(struct kretprobe *rp) { int ret = 0; struct kretprobe_instance *inst; @@ -986,21 +1033,21 @@ static int __kprobes __register_kretprobe(struct kretprobe *rp, rp->nmissed = 0; /* Establish function entry probe point */ - ret = __register_kprobe(&rp->kp, called_from); + ret = register_kprobe(&rp->kp); if (ret != 0) free_rp_inst(rp); return ret; } +EXPORT_SYMBOL_GPL(register_kretprobe); -static int __kprobes __register_kretprobes(struct kretprobe **rps, int num, - unsigned long called_from) +int __kprobes register_kretprobes(struct kretprobe **rps, int num) { int ret = 0, i; if (num <= 0) return -EINVAL; for (i = 0; i < num; i++) { - ret = __register_kretprobe(rps[i], called_from); + ret = register_kretprobe(rps[i]); if (ret < 0) { if (i > 0) unregister_kretprobes(rps, i); @@ -1009,23 +1056,13 @@ static int __kprobes __register_kretprobes(struct kretprobe **rps, int num, } return ret; } - -int __kprobes register_kretprobe(struct kretprobe *rp) -{ - return __register_kretprobes(&rp, 1, - (unsigned long)__builtin_return_address(0)); -} +EXPORT_SYMBOL_GPL(register_kretprobes); void __kprobes unregister_kretprobe(struct kretprobe *rp) { unregister_kretprobes(&rp, 1); } - -int __kprobes register_kretprobes(struct kretprobe **rps, int num) -{ - return __register_kretprobes(rps, num, - (unsigned long)__builtin_return_address(0)); -} +EXPORT_SYMBOL_GPL(unregister_kretprobe); void __kprobes unregister_kretprobes(struct kretprobe **rps, int num) { @@ -1047,24 +1084,30 @@ void __kprobes unregister_kretprobes(struct kretprobe **rps, int num) } } } +EXPORT_SYMBOL_GPL(unregister_kretprobes); #else /* CONFIG_KRETPROBES */ int __kprobes register_kretprobe(struct kretprobe *rp) { return -ENOSYS; } +EXPORT_SYMBOL_GPL(register_kretprobe); int __kprobes register_kretprobes(struct kretprobe **rps, int num) { return -ENOSYS; } +EXPORT_SYMBOL_GPL(register_kretprobes); + void __kprobes unregister_kretprobe(struct kretprobe *rp) { } +EXPORT_SYMBOL_GPL(unregister_kretprobe); void __kprobes unregister_kretprobes(struct kretprobe **rps, int num) { } +EXPORT_SYMBOL_GPL(unregister_kretprobes); static int __kprobes pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) @@ -1074,6 +1117,73 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p, #endif /* CONFIG_KRETPROBES */ +/* Set the kprobe gone and remove its instruction buffer. */ +static void __kprobes kill_kprobe(struct kprobe *p) +{ + struct kprobe *kp; + + p->flags |= KPROBE_FLAG_GONE; + if (p->pre_handler == aggr_pre_handler) { + /* + * If this is an aggr_kprobe, we have to list all the + * chained probes and mark them GONE. + */ + list_for_each_entry_rcu(kp, &p->list, list) + kp->flags |= KPROBE_FLAG_GONE; + p->post_handler = NULL; + p->break_handler = NULL; + } + /* + * Here, we can remove insn_slot safely, because no thread calls + * the original probed function (which will be freed soon) any more. + */ + arch_remove_kprobe(p); +} + +/* Module notifier call back, checking kprobes on the module */ +static int __kprobes kprobes_module_callback(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct module *mod = data; + struct hlist_head *head; + struct hlist_node *node; + struct kprobe *p; + unsigned int i; + int checkcore = (val == MODULE_STATE_GOING); + + if (val != MODULE_STATE_GOING && val != MODULE_STATE_LIVE) + return NOTIFY_DONE; + + /* + * When MODULE_STATE_GOING was notified, both of module .text and + * .init.text sections would be freed. When MODULE_STATE_LIVE was + * notified, only .init.text section would be freed. We need to + * disable kprobes which have been inserted in the sections. + */ + mutex_lock(&kprobe_mutex); + for (i = 0; i < KPROBE_TABLE_SIZE; i++) { + head = &kprobe_table[i]; + hlist_for_each_entry_rcu(p, node, head, hlist) + if (within_module_init((unsigned long)p->addr, mod) || + (checkcore && + within_module_core((unsigned long)p->addr, mod))) { + /* + * The vaddr this probe is installed will soon + * be vfreed buy not synced to disk. Hence, + * disarming the breakpoint isn't needed. + */ + kill_kprobe(p); + } + } + mutex_unlock(&kprobe_mutex); + return NOTIFY_DONE; +} + +static struct notifier_block kprobe_module_nb = { + .notifier_call = kprobes_module_callback, + .priority = 0 +}; + static int __init init_kprobes(void) { int i, err = 0; @@ -1124,12 +1234,15 @@ static int __init init_kprobes(void) } } - /* By default, kprobes are enabled */ - kprobe_enabled = true; + /* By default, kprobes are armed */ + kprobes_all_disarmed = false; err = arch_init_kprobes(); if (!err) err = register_die_notifier(&kprobe_exceptions_nb); + if (!err) + err = register_module_notifier(&kprobe_module_nb); + kprobes_initialized = (err == 0); if (!err) @@ -1150,10 +1263,18 @@ static void __kprobes report_probe(struct seq_file *pi, struct kprobe *p, else kprobe_type = "k"; if (sym) - seq_printf(pi, "%p %s %s+0x%x %s\n", p->addr, kprobe_type, - sym, offset, (modname ? modname : " ")); + 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\n", p->addr, kprobe_type, p->addr); + 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) @@ -1218,7 +1339,72 @@ static struct file_operations debugfs_kprobes_operations = { .release = seq_release, }; -static void __kprobes enable_all_kprobes(void) +/* 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)) + arch_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)) + arch_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; struct hlist_node *node; @@ -1227,17 +1413,20 @@ static void __kprobes enable_all_kprobes(void) mutex_lock(&kprobe_mutex); - /* If kprobes are already enabled, just return */ - if (kprobe_enabled) + /* If kprobes are armed, just return */ + if (!kprobes_all_disarmed) goto already_enabled; + mutex_lock(&text_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) - arch_arm_kprobe(p); + if (!kprobe_disabled(p)) + arch_arm_kprobe(p); } + mutex_unlock(&text_mutex); - kprobe_enabled = true; + kprobes_all_disarmed = false; printk(KERN_INFO "Kprobes globally enabled\n"); already_enabled: @@ -1245,7 +1434,7 @@ already_enabled: return; } -static void __kprobes disable_all_kprobes(void) +static void __kprobes disarm_all_kprobes(void) { struct hlist_head *head; struct hlist_node *node; @@ -1254,20 +1443,22 @@ static void __kprobes disable_all_kprobes(void) mutex_lock(&kprobe_mutex); - /* If kprobes are already disabled, just return */ - if (!kprobe_enabled) + /* If kprobes are already disarmed, just return */ + if (kprobes_all_disarmed) goto already_disabled; - kprobe_enabled = false; + kprobes_all_disarmed = true; printk(KERN_INFO "Kprobes globally disabled\n"); + mutex_lock(&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)) + if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p)) arch_disarm_kprobe(p); } } + mutex_unlock(&text_mutex); mutex_unlock(&kprobe_mutex); /* Allow all currently running kprobes to complete */ synchronize_sched(); @@ -1288,7 +1479,7 @@ static ssize_t read_enabled_file_bool(struct file *file, { char buf[3]; - if (kprobe_enabled) + if (!kprobes_all_disarmed) buf[0] = '1'; else buf[0] = '0'; @@ -1311,12 +1502,12 @@ static ssize_t write_enabled_file_bool(struct file *file, case 'y': case 'Y': case '1': - enable_all_kprobes(); + arm_all_kprobes(); break; case 'n': case 'N': case '0': - disable_all_kprobes(); + disarm_all_kprobes(); break; } @@ -1359,16 +1550,5 @@ late_initcall(debugfs_kprobe_init); module_init(init_kprobes); -EXPORT_SYMBOL_GPL(register_kprobe); -EXPORT_SYMBOL_GPL(unregister_kprobe); -EXPORT_SYMBOL_GPL(register_kprobes); -EXPORT_SYMBOL_GPL(unregister_kprobes); -EXPORT_SYMBOL_GPL(register_jprobe); -EXPORT_SYMBOL_GPL(unregister_jprobe); -EXPORT_SYMBOL_GPL(register_jprobes); -EXPORT_SYMBOL_GPL(unregister_jprobes); +/* defined in arch/.../kernel/kprobes.c */ EXPORT_SYMBOL_GPL(jprobe_return); -EXPORT_SYMBOL_GPL(register_kretprobe); -EXPORT_SYMBOL_GPL(unregister_kretprobe); -EXPORT_SYMBOL_GPL(register_kretprobes); -EXPORT_SYMBOL_GPL(unregister_kretprobes);