Kernel: Use Userspace<T> for the uname syscall

1 files changed, 12 insertions, 6 deletions

diff --git a/Kernel/Syscalls/uname.cpp b/Kernel/Syscalls/uname.cpp
index 140e084b37..33172798dd 100644
--- a/Kernel/Syscalls/uname.cpp
+++ b/Kernel/Syscalls/uname.cpp
@@ -28,7 +28,7 @@
 
 namespace Kernel {
 
-int Process::sys$uname(utsname* buf)
+int Process::sys$uname(Userspace<utsname*> buf)
 {
     extern String* g_hostname;
     extern Lock* g_hostname_lock;
@@ -36,14 +36,20 @@ int Process::sys$uname(utsname* buf)
     REQUIRE_PROMISE(stdio);
     if (!validate_write_typed(buf))
         return -EFAULT;
+
+
     LOCKER(*g_hostname_lock, Lock::Mode::Shared);
     if (g_hostname->length() + 1 > sizeof(utsname::nodename))
         return -ENAMETOOLONG;
-    copy_to_user(buf->sysname, "SerenityOS", 11);
-    copy_to_user(buf->release, "1.0-dev", 8);
-    copy_to_user(buf->version, "FIXME", 6);
-    copy_to_user(buf->machine, "i686", 5);
-    copy_to_user(buf->nodename, g_hostname->characters(), g_hostname->length() + 1);
+
+    // We have already validated the entire utsname struct at this
+    // point, there is no need to re-validate every write to the struct.
+    utsname* user_buf = buf.unsafe_userspace_ptr();
+    copy_to_user(user_buf->sysname, "SerenityOS", 11);
+    copy_to_user(user_buf->release, "1.0-dev", 8);
+    copy_to_user(user_buf->version, "FIXME", 6);
+    copy_to_user(user_buf->machine, "i686", 5);
+    copy_to_user(user_buf->nodename, g_hostname->characters(), g_hostname->length() + 1);
     return 0;
 }