2 files changed, 82 insertions, 21 deletions

diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 7be868bf25c6..3b79bd938330 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -39,6 +39,16 @@ struct jump_label_module_entry {
         struct module *mod;
 };
 
+void jump_label_lock(void)
+{
+        mutex_lock(&jump_label_mutex);
+}
+
+void jump_label_unlock(void)
+{
+        mutex_unlock(&jump_label_mutex);
+}
+
 static int jump_label_cmp(const void *a, const void *b)
 {
         const struct jump_entry *jea = a;
@@ -152,7 +162,7 @@ void jump_label_update(unsigned long key, enum jump_label_type type)
         struct jump_label_module_entry *e_module;
         int count;
 
-        mutex_lock(&jump_label_mutex);
+        jump_label_lock();
         entry = get_jump_label_entry((jump_label_t)key);
         if (entry) {
                 count = entry->nr_entries;
@@ -168,13 +178,14 @@ void jump_label_update(unsigned long key, enum jump_label_type type)
                         count = e_module->nr_entries;
                         iter = e_module->table;
                         while (count--) {
-                                if (kernel_text_address(iter->code))
+                                if (iter->key &&
+                                                kernel_text_address(iter->code))
                                         arch_jump_label_transform(iter, type);
                                 iter++;
                         }
                 }
         }
-        mutex_unlock(&jump_label_mutex);
+        jump_label_unlock();
 }
 
 static int addr_conflict(struct jump_entry *entry, void *start, void *end)
@@ -231,6 +242,7 @@ out:
  * overlaps with any of the jump label patch addresses. Code
  * that wants to modify kernel text should first verify that
  * it does not overlap with any of the jump label addresses.
+ * Caller must hold jump_label_mutex.
  *
  * returns 1 if there is an overlap, 0 otherwise
  */
@@ -241,7 +253,6 @@ int jump_label_text_reserved(void *start, void *end)
         struct jump_entry *iter_stop = __start___jump_table;
         int conflict = 0;
 
-        mutex_lock(&jump_label_mutex);
         iter = iter_start;
         while (iter < iter_stop) {
                 if (addr_conflict(iter, start, end)) {
@@ -256,10 +267,16 @@ int jump_label_text_reserved(void *start, void *end)
         conflict = module_conflict(start, end);
 #endif
 out:
-        mutex_unlock(&jump_label_mutex);
         return conflict;
 }
 
+/*
+ * Not all archs need this.
+ */
+void __weak arch_jump_label_text_poke_early(jump_label_t addr)
+{
+}
+
 static __init int init_jump_label(void)
 {
         int ret;
@@ -267,7 +284,7 @@ static __init int init_jump_label(void)
         struct jump_entry *iter_stop = __stop___jump_table;
         struct jump_entry *iter;
 
-        mutex_lock(&jump_label_mutex);
+        jump_label_lock();
         ret = build_jump_label_hashtable(__start___jump_table,
                                          __stop___jump_table);
         iter = iter_start;
@@ -275,7 +292,7 @@ static __init int init_jump_label(void)
                 arch_jump_label_text_poke_early(iter->code);
                 iter++;
         }
-        mutex_unlock(&jump_label_mutex);
+        jump_label_unlock();
         return ret;
 }
 early_initcall(init_jump_label);
@@ -366,6 +383,39 @@ static void remove_jump_label_module(struct module *mod)
         }
 }
 
+static void remove_jump_label_module_init(struct module *mod)
+{
+        struct hlist_head *head;
+        struct hlist_node *node, *node_next, *module_node, *module_node_next;
+        struct jump_label_entry *e;
+        struct jump_label_module_entry *e_module;
+        struct jump_entry *iter;
+        int i, count;
+
+        /* if the module doesn't have jump label entries, just return */
+        if (!mod->num_jump_entries)
+                return;
+
+        for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
+                head = &jump_label_table[i];
+                hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
+                        hlist_for_each_entry_safe(e_module, module_node,
+                                                  module_node_next,
+                                                  &(e->modules), hlist) {
+                                if (e_module->mod != mod)
+                                        continue;
+                                count = e_module->nr_entries;
+                                iter = e_module->table;
+                                while (count--) {
+                                        if (within_module_init(iter->code, mod))
+                                                iter->key = 0;
+                                        iter++;
+                                }
+                        }
+                }
+        }
+}
+
 static int
 jump_label_module_notify(struct notifier_block *self, unsigned long val,
                          void *data)
@@ -375,16 +425,21 @@ jump_label_module_notify(struct notifier_block *self, unsigned long val,
 
         switch (val) {
         case MODULE_STATE_COMING:
-                mutex_lock(&jump_label_mutex);
+                jump_label_lock();
                 ret = add_jump_label_module(mod);
                 if (ret)
                         remove_jump_label_module(mod);
-                mutex_unlock(&jump_label_mutex);
+                jump_label_unlock();
                 break;
         case MODULE_STATE_GOING:
-                mutex_lock(&jump_label_mutex);
+                jump_label_lock();
                 remove_jump_label_module(mod);
-                mutex_unlock(&jump_label_mutex);
+                jump_label_unlock();
+                break;
+        case MODULE_STATE_LIVE:
+                jump_label_lock();
+                remove_jump_label_module_init(mod);
+                jump_label_unlock();
                 break;
         }
         return ret;
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 99865c33a60d..9737a76e106f 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1145,14 +1145,13 @@ int __kprobes register_kprobe(struct kprobe *p)
         if (ret)
                 return ret;
 
+        jump_label_lock();
         preempt_disable();
         if (!kernel_text_address((unsigned long) p->addr) ||
             in_kprobes_functions((unsigned long) p->addr) ||
             ftrace_text_reserved(p->addr, p->addr) ||
-            jump_label_text_reserved(p->addr, p->addr)) {
-                preempt_enable();
-                return -EINVAL;
-        }
+            jump_label_text_reserved(p->addr, p->addr))
+                goto fail_with_jump_label;
 
         /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
         p->flags &= KPROBE_FLAG_DISABLED;
@@ -1166,10 +1165,9 @@ int __kprobes register_kprobe(struct kprobe *p)
                  * We must hold a refcount of the probed module while updating
                  * its code to prohibit unexpected unloading.
                  */
-                if (unlikely(!try_module_get(probed_mod))) {
-                        preempt_enable();
-                        return -EINVAL;
-                }
+                if (unlikely(!try_module_get(probed_mod)))
+                        goto fail_with_jump_label;
+
                 /*
                  * If the module freed .init.text, we couldn't insert
                  * kprobes in there.
@@ -1177,16 +1175,18 @@ int __kprobes register_kprobe(struct kprobe *p)
                 if (within_module_init((unsigned long)p->addr, probed_mod) &&
                     probed_mod->state != MODULE_STATE_COMING) {
                         module_put(probed_mod);
-                        preempt_enable();
-                        return -EINVAL;
+                        goto fail_with_jump_label;
                 }
         }
         preempt_enable();
+        jump_label_unlock();
 
         p->nmissed = 0;
         INIT_LIST_HEAD(&p->list);
         mutex_lock(&kprobe_mutex);
 
+        jump_label_lock(); /* needed to call jump_label_text_reserved() */
+
         get_online_cpus();      /* For avoiding text_mutex deadlock. */
         mutex_lock(&text_mutex);
 
@@ -1214,12 +1214,18 @@ int __kprobes register_kprobe(struct kprobe *p)
 out:
         mutex_unlock(&text_mutex);
         put_online_cpus();
+        jump_label_unlock();
         mutex_unlock(&kprobe_mutex);
 
         if (probed_mod)
                 module_put(probed_mod);
 
         return ret;
+
+fail_with_jump_label:
+        preempt_enable();
+        jump_label_unlock();
+        return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(register_kprobe);