[S390] uaccess error handling.

Consider return values for all user space access function and
return -EFAULT on error.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index 2001767e1dc7..5b33f823863a 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -757,7 +757,9 @@ asmlinkage long sys32_sysctl(struct __sysctl_args32 __user *args)
                             put_user(oldlen, (u32 __user *)compat_ptr(tmp.oldlenp)))
                                 error = -EFAULT;
                 }
-                copy_to_user(args->__unused, tmp.__unused, sizeof(tmp.__unused));
+                if (copy_to_user(args->__unused, tmp.__unused,
+                                 sizeof(tmp.__unused)))
+                        error = -EFAULT;
         }
         return error;
 }