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-rw-r--r--mm/kasan/kasan_test_module.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/mm/kasan/kasan_test_module.c b/mm/kasan/kasan_test_module.c
new file mode 100644
index 000000000000..e4ca82dc2c16
--- /dev/null
+++ b/mm/kasan/kasan_test_module.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Author: Andrey Ryabinin <a.ryabinin@samsung.com>
+ */
+
+#define pr_fmt(fmt) "kasan test: %s " fmt, __func__
+
+#include <linux/mman.h>
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include "kasan.h"
+
+static noinline void __init copy_user_test(void)
+{
+ char *kmem;
+ char __user *usermem;
+ size_t size = 128 - KASAN_GRANULE_SIZE;
+ int __maybe_unused unused;
+
+ kmem = kmalloc(size, GFP_KERNEL);
+ if (!kmem)
+ return;
+
+ usermem = (char __user *)vm_mmap(NULL, 0, PAGE_SIZE,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0);
+ if (IS_ERR(usermem)) {
+ pr_err("Failed to allocate user memory\n");
+ kfree(kmem);
+ return;
+ }
+
+ OPTIMIZER_HIDE_VAR(size);
+
+ pr_info("out-of-bounds in copy_from_user()\n");
+ unused = copy_from_user(kmem, usermem, size + 1);
+
+ pr_info("out-of-bounds in copy_to_user()\n");
+ unused = copy_to_user(usermem, kmem, size + 1);
+
+ pr_info("out-of-bounds in __copy_from_user()\n");
+ unused = __copy_from_user(kmem, usermem, size + 1);
+
+ pr_info("out-of-bounds in __copy_to_user()\n");
+ unused = __copy_to_user(usermem, kmem, size + 1);
+
+ pr_info("out-of-bounds in __copy_from_user_inatomic()\n");
+ unused = __copy_from_user_inatomic(kmem, usermem, size + 1);
+
+ pr_info("out-of-bounds in __copy_to_user_inatomic()\n");
+ unused = __copy_to_user_inatomic(usermem, kmem, size + 1);
+
+ pr_info("out-of-bounds in strncpy_from_user()\n");
+ unused = strncpy_from_user(kmem, usermem, size + 1);
+
+ vm_munmap((unsigned long)usermem, PAGE_SIZE);
+ kfree(kmem);
+}
+
+static struct kasan_rcu_info {
+ int i;
+ struct rcu_head rcu;
+} *global_rcu_ptr;
+
+static noinline void __init kasan_rcu_reclaim(struct rcu_head *rp)
+{
+ struct kasan_rcu_info *fp = container_of(rp,
+ struct kasan_rcu_info, rcu);
+
+ kfree(fp);
+ ((volatile struct kasan_rcu_info *)fp)->i;
+}
+
+static noinline void __init kasan_rcu_uaf(void)
+{
+ struct kasan_rcu_info *ptr;
+
+ pr_info("use-after-free in kasan_rcu_reclaim\n");
+ ptr = kmalloc(sizeof(struct kasan_rcu_info), GFP_KERNEL);
+ if (!ptr) {
+ pr_err("Allocation failed\n");
+ return;
+ }
+
+ global_rcu_ptr = rcu_dereference_protected(ptr, NULL);
+ call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim);
+}
+
+static noinline void __init kasan_workqueue_work(struct work_struct *work)
+{
+ kfree(work);
+}
+
+static noinline void __init kasan_workqueue_uaf(void)
+{
+ struct workqueue_struct *workqueue;
+ struct work_struct *work;
+
+ workqueue = create_workqueue("kasan_wq_test");
+ if (!workqueue) {
+ pr_err("Allocation failed\n");
+ return;
+ }
+ work = kmalloc(sizeof(struct work_struct), GFP_KERNEL);
+ if (!work) {
+ pr_err("Allocation failed\n");
+ return;
+ }
+
+ INIT_WORK(work, kasan_workqueue_work);
+ queue_work(workqueue, work);
+ destroy_workqueue(workqueue);
+
+ pr_info("use-after-free on workqueue\n");
+ ((volatile struct work_struct *)work)->data;
+}
+
+static int __init test_kasan_module_init(void)
+{
+ /*
+ * Temporarily enable multi-shot mode. Otherwise, KASAN would only
+ * report the first detected bug and panic the kernel if panic_on_warn
+ * is enabled.
+ */
+ bool multishot = kasan_save_enable_multi_shot();
+
+ copy_user_test();
+ kasan_rcu_uaf();
+ kasan_workqueue_uaf();
+
+ kasan_restore_multi_shot(multishot);
+ return -EAGAIN;
+}
+
+module_init(test_kasan_module_init);
+MODULE_LICENSE("GPL");