s390/Kconfig: make use of 'depends on cc-option'

[linux-2.6-microblaze.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index f9572f4..1f6c45f 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2525,39 +2525,19 @@ SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
 #ifdef __ARCH_WANT_SYS_CLONE3
 noinline static int copy_clone_args_from_user(struct kernel_clone_args *kargs,
                                              struct clone_args __user *uargs,
-                                             size_t size)
+                                             size_t usize)
 {
+       int err;
        struct clone_args args;
 
-       if (unlikely(size > PAGE_SIZE))
+       if (unlikely(usize > PAGE_SIZE))
                return -E2BIG;
-
-       if (unlikely(size < sizeof(struct clone_args)))
+       if (unlikely(usize < CLONE_ARGS_SIZE_VER0))
                return -EINVAL;
 
-       if (unlikely(!access_ok(uargs, size)))
-               return -EFAULT;
-
-       if (size > sizeof(struct clone_args)) {
-               unsigned char __user *addr;
-               unsigned char __user *end;
-               unsigned char val;
-
-               addr = (void __user *)uargs + sizeof(struct clone_args);
-               end = (void __user *)uargs + size;
-
-               for (; addr < end; addr++) {
-                       if (get_user(val, addr))
-                               return -EFAULT;
-                       if (val)
-                               return -E2BIG;
-               }
-
-               size = sizeof(struct clone_args);
-       }
-
-       if (copy_from_user(&args, uargs, size))
-               return -EFAULT;
+       err = copy_struct_from_user(&args, sizeof(args), uargs, usize);
+       if (err)
+               return err;
 
        /*
         * Verify that higher 32bits of exit_signal are unset and that
@@ -2604,6 +2584,17 @@ static bool clone3_args_valid(const struct kernel_clone_args *kargs)
        return true;
 }
 
+/**
+ * clone3 - create a new process with specific properties
+ * @uargs: argument structure
+ * @size:  size of @uargs
+ *
+ * clone3() is the extensible successor to clone()/clone2().
+ * It takes a struct as argument that is versioned by its size.
+ *
+ * Return: On success, a positive PID for the child process.
+ *         On error, a negative errno number.
+ */
 SYSCALL_DEFINE2(clone3, struct clone_args __user *, uargs, size_t, size)
 {
        int err;