[Patch] fs/binfmt_elf.c: fix wrong return values

create_elf_tables() returns 0 on success. But when strnlen_user() "fails",
it returns 0 directly. So this is wrong.

Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/binfmt_elf.c

@@ -256,7 +256,7 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
 			return -EFAULT;
 		len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
 		if (!len || len > MAX_ARG_STRLEN)
-			return 0;
+			return -EINVAL;
 		p += len;
 	}
 	if (__put_user(0, argv))
@@ -268,7 +268,7 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
 			return -EFAULT;
 		len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
 		if (!len || len > MAX_ARG_STRLEN)
-			return 0;
+			return -EINVAL;
 		p += len;
 	}
 	if (__put_user(0, envp))