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-rw-r--r--kernel/kprobes.c51
1 files changed, 49 insertions, 2 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 66f1818d4762..4f918dd28fb7 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -599,11 +599,12 @@ static void kprobe_optimizer(struct work_struct *work)
mutex_unlock(&module_mutex);
mutex_unlock(&text_mutex);
cpus_read_unlock();
- mutex_unlock(&kprobe_mutex);
/* Step 5: Kick optimizer again if needed */
if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list))
kick_kprobe_optimizer();
+
+ mutex_unlock(&kprobe_mutex);
}
/* Wait for completing optimization and unoptimization */
@@ -1217,6 +1218,26 @@ __releases(hlist_lock)
}
NOKPROBE_SYMBOL(kretprobe_table_unlock);
+struct kprobe kprobe_busy = {
+ .addr = (void *) get_kprobe,
+};
+
+void kprobe_busy_begin(void)
+{
+ struct kprobe_ctlblk *kcb;
+
+ preempt_disable();
+ __this_cpu_write(current_kprobe, &kprobe_busy);
+ kcb = get_kprobe_ctlblk();
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+}
+
+void kprobe_busy_end(void)
+{
+ __this_cpu_write(current_kprobe, NULL);
+ preempt_enable();
+}
+
/*
* This function is called from finish_task_switch when task tk becomes dead,
* so that we can recycle any function-return probe instances associated
@@ -1234,6 +1255,8 @@ void kprobe_flush_task(struct task_struct *tk)
/* Early boot. kretprobe_table_locks not yet initialized. */
return;
+ kprobe_busy_begin();
+
INIT_HLIST_HEAD(&empty_rp);
hash = hash_ptr(tk, KPROBE_HASH_BITS);
head = &kretprobe_inst_table[hash];
@@ -1247,6 +1270,8 @@ void kprobe_flush_task(struct task_struct *tk)
hlist_del(&ri->hlist);
kfree(ri);
}
+
+ kprobe_busy_end();
}
NOKPROBE_SYMBOL(kprobe_flush_task);
@@ -1964,6 +1989,10 @@ int register_kretprobe(struct kretprobe *rp)
if (!kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset))
return -EINVAL;
+ /* If only rp->kp.addr is specified, check reregistering kprobes */
+ if (rp->kp.addr && check_kprobe_rereg(&rp->kp))
+ return -EINVAL;
+
if (kretprobe_blacklist_size) {
addr = kprobe_addr(&rp->kp);
if (IS_ERR(addr))
@@ -1975,6 +2004,9 @@ int register_kretprobe(struct kretprobe *rp)
}
}
+ if (rp->data_size > KRETPROBE_MAX_DATA_SIZE)
+ return -E2BIG;
+
rp->kp.pre_handler = pre_handler_kretprobe;
rp->kp.post_handler = NULL;
rp->kp.fault_handler = NULL;
@@ -2092,6 +2124,9 @@ static void kill_kprobe(struct kprobe *p)
{
struct kprobe *kp;
+ if (WARN_ON_ONCE(kprobe_gone(p)))
+ return;
+
p->flags |= KPROBE_FLAG_GONE;
if (kprobe_aggrprobe(p)) {
/*
@@ -2109,6 +2144,14 @@ static void kill_kprobe(struct kprobe *p)
* the original probed function (which will be freed soon) any more.
*/
arch_remove_kprobe(p);
+
+ /*
+ * The module is going away. We should disarm the kprobe which
+ * is using ftrace, because ftrace framework is still available at
+ * MODULE_STATE_GOING notification.
+ */
+ if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
+ disarm_kprobe_ftrace(p);
}
/* Disable one kprobe */
@@ -2227,7 +2270,10 @@ static int kprobes_module_callback(struct notifier_block *nb,
mutex_lock(&kprobe_mutex);
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
- hlist_for_each_entry_rcu(p, head, hlist)
+ hlist_for_each_entry_rcu(p, head, hlist) {
+ if (kprobe_gone(p))
+ continue;
+
if (within_module_init((unsigned long)p->addr, mod) ||
(checkcore &&
within_module_core((unsigned long)p->addr, mod))) {
@@ -2244,6 +2290,7 @@ static int kprobes_module_callback(struct notifier_block *nb,
*/
kill_kprobe(p);
}
+ }
}
mutex_unlock(&kprobe_mutex);
return NOTIFY_DONE;