irq/matrix: Fix memory overallocation

[mirror_ubuntu-bionic-kernel.git] / kernel / kprobes.c

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 0df0b66b17c2194406a18ec4ed135d273b144c1d..6ede02bb05ac406090301aceeadc63cf1e6425a7 100644 (file)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -483,6 +483,7 @@ static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer);
  */
 static void do_optimize_kprobes(void)
 {
+       lockdep_assert_held(&text_mutex);
        /*
         * The optimization/unoptimization refers online_cpus via
         * stop_machine() and cpu-hotplug modifies online_cpus.
@@ -500,9 +501,7 @@ static void do_optimize_kprobes(void)
            list_empty(&optimizing_list))
                return;
 
-       mutex_lock(&text_mutex);
        arch_optimize_kprobes(&optimizing_list);
-       mutex_unlock(&text_mutex);
 }
 
 /*
@@ -513,6 +512,7 @@ static void do_unoptimize_kprobes(void)
 {
        struct optimized_kprobe *op, *tmp;
 
+       lockdep_assert_held(&text_mutex);
        /* See comment in do_optimize_kprobes() */
        lockdep_assert_cpus_held();
 
@@ -520,7 +520,6 @@ static void do_unoptimize_kprobes(void)
        if (list_empty(&unoptimizing_list))
                return;
 
-       mutex_lock(&text_mutex);
        arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
        /* Loop free_list for disarming */
        list_for_each_entry_safe(op, tmp, &freeing_list, list) {
@@ -537,7 +536,6 @@ static void do_unoptimize_kprobes(void)
                } else
                        list_del_init(&op->list);
        }
-       mutex_unlock(&text_mutex);
 }
 
 /* Reclaim all kprobes on the free_list */
@@ -546,8 +544,14 @@ static void do_free_cleaned_kprobes(void)
        struct optimized_kprobe *op, *tmp;
 
        list_for_each_entry_safe(op, tmp, &freeing_list, list) {
-               BUG_ON(!kprobe_unused(&op->kp));
                list_del_init(&op->list);
+               if (WARN_ON_ONCE(!kprobe_unused(&op->kp))) {
+                       /*
+                        * This must not happen, but if there is a kprobe
+                        * still in use, keep it on kprobes hash list.
+                        */
+                       continue;
+               }
                free_aggr_kprobe(&op->kp);
        }
 }
@@ -563,6 +567,7 @@ static void kprobe_optimizer(struct work_struct *work)
 {
        mutex_lock(&kprobe_mutex);
        cpus_read_lock();
+       mutex_lock(&text_mutex);
        /* Lock modules while optimizing kprobes */
        mutex_lock(&module_mutex);
 
@@ -590,6 +595,7 @@ static void kprobe_optimizer(struct work_struct *work)
        do_free_cleaned_kprobes();
 
        mutex_unlock(&module_mutex);
+       mutex_unlock(&text_mutex);
        cpus_read_unlock();
        mutex_unlock(&kprobe_mutex);
 
@@ -703,7 +709,6 @@ static void unoptimize_kprobe(struct kprobe *p, bool force)
 static int reuse_unused_kprobe(struct kprobe *ap)
 {
        struct optimized_kprobe *op;
-       int ret;
 
        BUG_ON(!kprobe_unused(ap));
        /*
@@ -715,9 +720,8 @@ static int reuse_unused_kprobe(struct kprobe *ap)
        /* Enable the probe again */
        ap->flags &= ~KPROBE_FLAG_DISABLED;
        /* Optimize it again (remove from op->list) */
-       ret = kprobe_optready(ap);
-       if (ret)
-               return ret;
+       if (!kprobe_optready(ap))
+               return -EINVAL;
 
        optimize_kprobe(ap);
        return 0;
@@ -1501,7 +1505,8 @@ static int check_kprobe_address_safe(struct kprobe *p,
        /* Ensure it is not in reserved area nor out of text */
        if (!kernel_text_address((unsigned long) p->addr) ||
            within_kprobe_blacklist((unsigned long) p->addr) ||
-           jump_label_text_reserved(p->addr, p->addr)) {
+           jump_label_text_reserved(p->addr, p->addr) ||
+           find_bug((unsigned long)p->addr)) {
                ret = -EINVAL;
                goto out;
        }