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authorH. Peter Anvin <hpa@linux.intel.com>2014-02-07 11:27:30 -0800
committerH. Peter Anvin <hpa@linux.intel.com>2014-02-07 11:27:30 -0800
commita3b072cd180c12e8fe0ece9487b9065808327640 (patch)
tree62b982041be84748852d77cdf6ca5639ef40858f /lib/test_user_copy.c
parent75a1ba5b2c529db60ca49626bcaf0bddf4548438 (diff)
parent081cd62a010f97b5bc1d2b0cd123c5abc692b68a (diff)
downloadlinux-stericsson-a3b072cd180c12e8fe0ece9487b9065808327640.tar.gz
Merge tag 'efi-urgent' into x86/urgent
* Avoid WARN_ON() when mapping BGRT on Baytrail (EFI 32-bit). Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'lib/test_user_copy.c')
-rw-r--r--lib/test_user_copy.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c
new file mode 100644
index 000000000000..0ecef3e4690e
--- /dev/null
+++ b/lib/test_user_copy.c
@@ -0,0 +1,110 @@
+/*
+ * Kernel module for testing copy_to/from_user infrastructure.
+ *
+ * Copyright 2013 Google Inc. All Rights Reserved
+ *
+ * Authors:
+ * Kees Cook <keescook@chromium.org>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/mman.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+
+#define test(condition, msg) \
+({ \
+ int cond = (condition); \
+ if (cond) \
+ pr_warn("%s\n", msg); \
+ cond; \
+})
+
+static int __init test_user_copy_init(void)
+{
+ int ret = 0;
+ char *kmem;
+ char __user *usermem;
+ char *bad_usermem;
+ unsigned long user_addr;
+ unsigned long value = 0x5A;
+
+ kmem = kmalloc(PAGE_SIZE * 2, GFP_KERNEL);
+ if (!kmem)
+ return -ENOMEM;
+
+ user_addr = vm_mmap(NULL, 0, PAGE_SIZE * 2,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0);
+ if (user_addr >= (unsigned long)(TASK_SIZE)) {
+ pr_warn("Failed to allocate user memory\n");
+ kfree(kmem);
+ return -ENOMEM;
+ }
+
+ usermem = (char __user *)user_addr;
+ bad_usermem = (char *)user_addr;
+
+ /* Legitimate usage: none of these should fail. */
+ ret |= test(copy_from_user(kmem, usermem, PAGE_SIZE),
+ "legitimate copy_from_user failed");
+ ret |= test(copy_to_user(usermem, kmem, PAGE_SIZE),
+ "legitimate copy_to_user failed");
+ ret |= test(get_user(value, (unsigned long __user *)usermem),
+ "legitimate get_user failed");
+ ret |= test(put_user(value, (unsigned long __user *)usermem),
+ "legitimate put_user failed");
+
+ /* Invalid usage: none of these should succeed. */
+ ret |= test(!copy_from_user(kmem, (char __user *)(kmem + PAGE_SIZE),
+ PAGE_SIZE),
+ "illegal all-kernel copy_from_user passed");
+ ret |= test(!copy_from_user(bad_usermem, (char __user *)kmem,
+ PAGE_SIZE),
+ "illegal reversed copy_from_user passed");
+ ret |= test(!copy_to_user((char __user *)kmem, kmem + PAGE_SIZE,
+ PAGE_SIZE),
+ "illegal all-kernel copy_to_user passed");
+ ret |= test(!copy_to_user((char __user *)kmem, bad_usermem,
+ PAGE_SIZE),
+ "illegal reversed copy_to_user passed");
+ ret |= test(!get_user(value, (unsigned long __user *)kmem),
+ "illegal get_user passed");
+ ret |= test(!put_user(value, (unsigned long __user *)kmem),
+ "illegal put_user passed");
+
+ vm_munmap(user_addr, PAGE_SIZE * 2);
+ kfree(kmem);
+
+ if (ret == 0) {
+ pr_info("tests passed.\n");
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+module_init(test_user_copy_init);
+
+static void __exit test_user_copy_exit(void)
+{
+ pr_info("unloaded.\n");
+}
+
+module_exit(test_user_copy_exit);
+
+MODULE_AUTHOR("Kees Cook <keescook@chromium.org>");
+MODULE_LICENSE("GPL");