lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Mon, 06 Oct 2014 19:54:06 +0400
From:	Andrey Ryabinin <a.ryabinin@...sung.com>
To:	linux-kernel@...r.kernel.org
Cc:	Andrey Ryabinin <a.ryabinin@...sung.com>,
	Dmitry Vyukov <dvyukov@...gle.com>,
	Konstantin Serebryany <kcc@...gle.com>,
	Dmitry Chernenkov <dmitryc@...gle.com>,
	Andrey Konovalov <adech.fo@...il.com>,
	Yuri Gribov <tetra2005@...il.com>,
	Konstantin Khlebnikov <koct9i@...il.com>,
	Sasha Levin <sasha.levin@...cle.com>,
	Christoph Lameter <cl@...ux.com>,
	Joonsoo Kim <iamjoonsoo.kim@....com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Dave Hansen <dave.hansen@...el.com>,
	Andi Kleen <andi@...stfloor.org>,
	Vegard Nossum <vegard.nossum@...il.com>,
	"H. Peter Anvin" <hpa@...or.com>, Dave Jones <davej@...hat.com>,
	x86@...nel.org, linux-mm@...ck.org
Subject: [PATCH v4 12/13] lib: add kasan test module

This is a test module doing various nasty things like
out of bounds accesses, use after free. It is useful for testing
kernel debugging features like kernel address sanitizer.

It mostly concentrates on testing of slab allocator, but we
might want to add more different stuff here in future (like
stack/global variables out of bounds accesses and so on).

Signed-off-by: Andrey Ryabinin <a.ryabinin@...sung.com>
---
 lib/Kconfig.kasan |   8 ++
 lib/Makefile      |   1 +
 lib/test_kasan.c  | 254 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 263 insertions(+)
 create mode 100644 lib/test_kasan.c

diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index d16b899..94293c8 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -19,4 +19,12 @@ config KASAN_SHADOW_OFFSET
 	hex
 	default 0xdfffe90000000000 if X86_64
 
+config TEST_KASAN
+	tristate "Module for testing kasan for bug detection"
+	depends on m
+	help
+	  This is a test module doing various nasty things like
+	  out of bounds accesses, use after free. It is useful for testing
+	  kernel debugging features like kernel address sanitizer.
+
 endif
diff --git a/lib/Makefile b/lib/Makefile
index 84000ec..b387570 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_TEST_LKM) += test_module.o
 obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
 obj-$(CONFIG_TEST_BPF) += test_bpf.o
 obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o
+obj-$(CONFIG_TEST_KASAN) += test_kasan.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
diff --git a/lib/test_kasan.c b/lib/test_kasan.c
new file mode 100644
index 0000000..66a04eb
--- /dev/null
+++ b/lib/test_kasan.c
@@ -0,0 +1,254 @@
+/*
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Author: Andrey Ryabinin <a.ryabinin@...sung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#define pr_fmt(fmt) "kasan test: %s " fmt, __func__
+
+#include <linux/kernel.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/module.h>
+
+static noinline void __init kmalloc_oob_right(void)
+{
+	char *ptr;
+	size_t size = 123;
+
+	pr_info("out-of-bounds to right\n");
+	ptr = kmalloc(size , GFP_KERNEL);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	ptr[size] = 'x';
+	kfree(ptr);
+}
+
+static noinline void __init kmalloc_oob_left(void)
+{
+	char *ptr;
+	size_t size = 15;
+
+	pr_info("out-of-bounds to left\n");
+	ptr = kmalloc(size, GFP_KERNEL);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	*ptr = *(ptr - 1);
+	kfree(ptr);
+}
+
+static noinline void __init kmalloc_node_oob_right(void)
+{
+	char *ptr;
+	size_t size = 4096;
+
+	pr_info("kmalloc_node(): out-of-bounds to right\n");
+	ptr = kmalloc_node(size , GFP_KERNEL, 0);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	ptr[size] = 0;
+	kfree(ptr);
+}
+
+static noinline void __init kmalloc_large_oob_rigth(void)
+{
+	char *ptr;
+	size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
+
+	pr_info("kmalloc large allocation: out-of-bounds to right\n");
+	ptr = kmalloc(size , GFP_KERNEL);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	ptr[size] = 0;
+	kfree(ptr);
+}
+
+static noinline void __init kmalloc_oob_krealloc_more(void)
+{
+	char *ptr1, *ptr2;
+	size_t size1 = 17;
+	size_t size2 = 19;
+
+	pr_info("out-of-bounds after krealloc more\n");
+	ptr1 = kmalloc(size1, GFP_KERNEL);
+	ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
+	if (!ptr1 || !ptr2) {
+		pr_err("Allocation failed\n");
+		kfree(ptr1);
+		return;
+	}
+
+	ptr2[size2] = 'x';
+	kfree(ptr2);
+}
+
+static noinline void __init kmalloc_oob_krealloc_less(void)
+{
+	char *ptr1, *ptr2;
+	size_t size1 = 17;
+	size_t size2 = 15;
+
+	pr_info("out-of-bounds after krealloc less\n");
+	ptr1 = kmalloc(size1, GFP_KERNEL);
+	ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
+	if (!ptr1 || !ptr2) {
+		pr_err("Allocation failed\n");
+		kfree(ptr1);
+		return;
+	}
+	ptr2[size1] = 'x';
+	kfree(ptr2);
+}
+
+static noinline void __init kmalloc_oob_16(void)
+{
+	struct {
+		u64 words[2];
+	} *ptr1, *ptr2;
+
+	pr_info("kmalloc out-of-bounds for 16-bytes access\n");
+	ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL);
+	ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL);
+	if (!ptr1 || !ptr2) {
+		pr_err("Allocation failed\n");
+		kfree(ptr1);
+		kfree(ptr2);
+		return;
+	}
+	*ptr1 = *ptr2;
+	kfree(ptr1);
+	kfree(ptr2);
+}
+
+static noinline void __init kmalloc_oob_in_memset(void)
+{
+	char *ptr;
+	size_t size = 666;
+
+	pr_info("out-of-bounds in memset\n");
+	ptr = kmalloc(size, GFP_KERNEL);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	memset(ptr, 0, size+5);
+	kfree(ptr);
+}
+
+static noinline void __init kmalloc_uaf(void)
+{
+	char *ptr;
+	size_t size = 10;
+
+	pr_info("use-after-free\n");
+	ptr = kmalloc(size, GFP_KERNEL);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	kfree(ptr);
+	*(ptr + 8) = 'x';
+}
+
+static noinline void __init kmalloc_uaf_memset(void)
+{
+	char *ptr;
+	size_t size = 33;
+
+	pr_info("use-after-free in memset\n");
+	ptr = kmalloc(size, GFP_KERNEL);
+	if (!ptr) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	kfree(ptr);
+	memset(ptr, 0, size);
+}
+
+static noinline void __init kmalloc_uaf2(void)
+{
+	char *ptr1, *ptr2;
+	size_t size = 43;
+
+	pr_info("use-after-free after another kmalloc\n");
+	ptr1 = kmalloc(size, GFP_KERNEL);
+	if (!ptr1) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	kfree(ptr1);
+	ptr2 = kmalloc(size, GFP_KERNEL);
+	if (!ptr2) {
+		pr_err("Allocation failed\n");
+		return;
+	}
+
+	ptr1[40] = 'x';
+	kfree(ptr2);
+}
+
+static noinline void __init kmem_cache_oob(void)
+{
+	char *p;
+	size_t size = 200;
+	struct kmem_cache *cache = kmem_cache_create("test_cache",
+						size, 0,
+						0, NULL);
+	if (!cache) {
+		pr_err("Cache allocation failed\n");
+		return;
+	}
+	pr_info("out-of-bounds in kmem_cache_alloc\n");
+	p = kmem_cache_alloc(cache, GFP_KERNEL);
+	if (!p) {
+		pr_err("Allocation failed\n");
+		kmem_cache_destroy(cache);
+		return;
+	}
+
+	*p = p[size];
+	kmem_cache_free(cache, p);
+	kmem_cache_destroy(cache);
+}
+
+int __init kmalloc_tests_init(void)
+{
+	kmalloc_oob_right();
+	kmalloc_oob_left();
+	kmalloc_node_oob_right();
+	kmalloc_large_oob_rigth();
+	kmalloc_oob_krealloc_more();
+	kmalloc_oob_krealloc_less();
+	kmalloc_oob_16();
+	kmalloc_oob_in_memset();
+	kmalloc_uaf();
+	kmalloc_uaf_memset();
+	kmalloc_uaf2();
+	kmem_cache_oob();
+	return -EAGAIN;
+}
+
+module_init(kmalloc_tests_init);
+MODULE_LICENSE("GPL");
-- 
2.1.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists