From 3377cc74dffddcca25eee4256dd3d5635fdac6ba Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Thu, 5 Aug 2021 23:46:15 +0200
Subject: [PATCH] Kernel: Use try_copy_kstring_from_user() in sys$mount()

---
 Kernel/Syscalls/mount.cpp | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/Kernel/Syscalls/mount.cpp b/Kernel/Syscalls/mount.cpp
index f9444595e8..5bfcb5fec3 100644
--- a/Kernel/Syscalls/mount.cpp
+++ b/Kernel/Syscalls/mount.cpp
@@ -30,12 +30,15 @@ KResultOr<FlatPtr> Process::sys$mount(Userspace<const Syscall::SC_mount_params*>
         return EFAULT;
 
     auto source_fd = params.source_fd;
-    auto target = copy_string_from_user(params.target);
-    if (target.is_null())
-        return EFAULT;
-    auto fs_type = copy_string_from_user(params.fs_type);
-    if (fs_type.is_null())
-        return EFAULT;
+    auto target_or_error = try_copy_kstring_from_user(params.target);
+    if (target_or_error.is_error())
+        return target_or_error.error();
+    auto fs_type_or_error = try_copy_kstring_from_user(params.fs_type);
+    if (fs_type_or_error.is_error())
+        return fs_type_or_error.error();
+
+    auto target = target_or_error.value()->view();
+    auto fs_type = fs_type_or_error.value()->view();
 
     auto description = fds().file_description(source_fd);
     if (!description.is_null())