syscall: Check user manageability in deviceyByKind()

1 files changed, 4 insertions, 0 deletions

diff --git a/src/syscall.zig b/src/syscall.zig
index 32e8748..e3b54c9 100644
--- a/src/syscall.zig
+++ b/src/syscall.zig
@@ -135,12 +135,16 @@ fn threadId(proc: *const process.Info) usize {
     return proc.thread_id;
 }
 
+pub const DeviceError = error{KindNotUserManagable};
+
 // devicesByKind(kind: hwinfo.DevKind, devices: [*]hwinfo.Dev, len: usize) !usize
 fn devicesByKind(trap_frame: *const TrapFrame) !usize {
     const kind: hwinfo.DevKind = @enumFromInt(trap_frame.general_purpose_registers[10]);
     const devices: [*]hwinfo.Dev = @ptrFromInt(trap_frame.general_purpose_registers[11]);
     const len = trap_frame.general_purpose_registers[12];
 
+    if (!kind.isUserManagable()) return DeviceError.KindNotUserManagable;
+
     var i: usize = 0;
     var devs = try hwinfo.byKind(kind);
     while (try devs.next()) |dev| {