Add basic success/failure checking of copy_in_user() which copies data
from userspace to userspace (or kernel to kernel), and its unchecking
cousin __copy_in_user() which assumes that access_ok() has already been
used as appropriate.
The following cases are checked:
- __copy_in_user/copy_in_user from user to user should succeed.
- __copy_in_user/copy_in_user involving 1 or 2 kernel pointers should
not succeed.
- __copy_in_user/copy_in_user from kernel to kernel should succeed when
user address limit is set for kernel accesses.
New tests:
- legitimate copy_in_user
- legitimate __copy_in_user
- illegal all-kernel copy_in_user
- illegal copy_in_user to kernel
- illegal copy_in_user from kernel
- illegal all-kernel __copy_in_user
- illegal __copy_in_user to kernel
- illegal __copy_in_user from kernel
- legitimate all-kernel copy_in_user
- legitimate all-kernel __copy_in_user
Signed-off-by: James Hogan <james.ho...@imgtec.com>
Cc: Kees Cook <keesc...@chromium.org>
Cc: Andrew Morton <a...@linux-foundation.org>
---
lib/test_user_copy.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c
index 4ec2cfa916c1..310e796beef6 100644
--- a/lib/test_user_copy.c
+++ b/lib/test_user_copy.c
@@ -64,6 +64,8 @@ static int __init test_user_copy_init(void)
"legitimate copy_from_user failed");
ret |= test(copy_to_user(usermem, kmem, PAGE_SIZE),
"legitimate copy_to_user failed");
+ ret |= test(copy_in_user(usermem, usermem + PAGE_SIZE, PAGE_SIZE),
+ "legitimate copy_in_user failed");
ret |= test(get_user(value, (unsigned long __user *)usermem),
"legitimate get_user failed");
ret |= test(put_user(value, (unsigned long __user *)usermem),
@@ -79,6 +81,8 @@ static int __init test_user_copy_init(void)
"legitimate __copy_from_user failed");
ret |= test(__copy_to_user(usermem, kmem, PAGE_SIZE),
"legitimate __copy_to_user failed");
+ ret |= test(__copy_in_user(usermem, usermem + PAGE_SIZE, PAGE_SIZE),
+ "legitimate __copy_in_user failed");
ret |= test(__get_user(value, (unsigned long __user *)usermem),
"legitimate __get_user failed");
ret |= test(__put_user(value, (unsigned long __user *)usermem),
@@ -99,6 +103,15 @@ static int __init test_user_copy_init(void)
ret |= test(!copy_to_user((char __user *)kmem, bad_usermem,
PAGE_SIZE),
"illegal reversed copy_to_user passed");
+ ret |= test(!copy_in_user((char __user *)kmem,
+ (char __user *)(kmem + PAGE_SIZE), PAGE_SIZE),
+ "illegal all-kernel copy_in_user passed");
+ ret |= test(!copy_in_user((char __user *)kmem, usermem,
+ PAGE_SIZE),
+ "illegal copy_in_user to kernel passed");
+ ret |= test(!copy_in_user(usermem, (char __user *)kmem,
+ PAGE_SIZE),
+ "illegal copy_in_user from kernel passed");
ret |= test(!get_user(value, (unsigned long __user *)kmem),
"illegal get_user passed");
ret |= test(!put_user(value, (unsigned long __user *)kmem),
@@ -130,6 +143,16 @@ static int __init test_user_copy_init(void)
ret |= test(!__copy_to_user((char __user *)kmem, bad_usermem,
PAGE_SIZE),
"illegal reversed __copy_to_user passed");
+ ret |= test(!__copy_in_user((char __user *)kmem,
+ (char __user *)(kmem + PAGE_SIZE),
+ PAGE_SIZE),
+ "illegal all-kernel __copy_in_user passed");
+ ret |= test(!__copy_in_user((char __user *)kmem, usermem,
+ PAGE_SIZE),
+ "illegal __copy_in_user to kernel passed");
+ ret |= test(!__copy_in_user(usermem, (char __user *)kmem,
+ PAGE_SIZE),
+ "illegal __copy_in_user from kernel passed");
ret |= test(!__get_user(value, (unsigned long __user *)kmem),
"illegal __get_user passed");
ret |= test(!__put_user(value, (unsigned long __user *)kmem),
@@ -152,6 +175,9 @@ static int __init test_user_copy_init(void)
ret |= test(copy_to_user((char __user *)kmem, kmem + PAGE_SIZE,
PAGE_SIZE),
"legitimate all-kernel copy_to_user failed");
+ ret |= test(copy_in_user((char __user *)kmem,
+ (char __user *)(kmem + PAGE_SIZE), PAGE_SIZE),
+ "legitimate all-kernel copy_in_user failed");
ret |= test(get_user(value, (unsigned long __user *)kmem),
"legitimate kernel get_user failed");
ret |= test(put_user(value, (unsigned long __user *)kmem),
@@ -170,6 +196,10 @@ static int __init test_user_copy_init(void)
ret |= test(__copy_to_user((char __user *)kmem, kmem + PAGE_SIZE,
PAGE_SIZE),
"legitimate all-kernel __copy_to_user failed");
+ ret |= test(__copy_in_user((char __user *)kmem,
+ (char __user *)(kmem + PAGE_SIZE),
+ PAGE_SIZE),
+ "legitimate all-kernel __copy_in_user failed");
ret |= test(__get_user(value, (unsigned long __user *)kmem),
"legitimate kernel __get_user failed");
ret |= test(__put_user(value, (unsigned long __user *)kmem),
--
2.3.6
--
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