test: fix sparse warnings in user_copy tests

Sparse fix for "test: check copy_to/from_user boundary validation":

To keep sparse happy with the horrible things being done with the user
memory pointers, declare both __user and non-__user cases ahead of time to
avoid needing to do the casts later.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c
index b61f3e406e0b8d969c8c7da1c3ef697cc4842914..0ecef3e4690eb484a2e548ce49374145a776ef62 100644 (file)
--- a/lib/test_user_copy.c
+++ b/lib/test_user_copy.c
@@ -38,6 +38,7 @@ 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;
 
@@ -55,6 +56,7 @@ static int __init test_user_copy_init(void)
        }
 
        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),
@@ -70,13 +72,13 @@ static int __init test_user_copy_init(void)
        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((char *)usermem, (char __user *)kmem,
+       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, (char *)usermem,
+       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),