diff --git a/src/os/uefi/device.rs b/src/os/uefi/device.rs
index 4b0bf31..90a97b8 100644
--- a/src/os/uefi/device.rs
+++ b/src/os/uefi/device.rs
@@ -46,6 +46,8 @@ fn device_path_relation(a_path: &DevicePath, b_path: &DevicePath) -> DevicePath
 }
 
 fn esp_live_image(esp_handle: Handle, esp_device_path: &DevicePath) -> Option<Vec<u8>> {
+    const MAX_LIVE_IMAGE_PRELOAD: usize = 128 * 1024 * 1024;
+
     let mut esp_fs = match FileSystem::handle_protocol(esp_handle) {
         Ok(esp_fs) => esp_fs,
         Err(err) => {
@@ -87,9 +89,37 @@ fn esp_live_image(esp_handle: Handle, esp_device_path: &DevicePath) -> Option<V
     };
 
     let mut buffer = Vec::new();
+    let mut chunk = [0_u8; 64 * 1024];
+
+    loop {
+        let read = match live_image.read(&mut chunk) {
+            Ok(read) => read,
+            Err(err) => {
+                log::warn!(
+                    "Failed while reading {}\\redox-live.iso: {:?}",
+                    device_path_to_string(esp_device_path),
+                    err
+                );
+                return None;
+            }
+        };
+
+        if read == 0 {
+            break;
+        }
 
-    live_image.read_to_end(&mut buffer).unwrap();
+        if buffer.len().saturating_add(read) > MAX_LIVE_IMAGE_PRELOAD {
+            log::warn!(
+                "Skipping {}\\redox-live.iso preload: file exceeds {} MiB safety limit",
+                device_path_to_string(esp_device_path),
+                MAX_LIVE_IMAGE_PRELOAD / 1024 / 1024
+            );
+            return None;
+        }
+
+        buffer.extend_from_slice(&chunk[..read]);
+    }
 
     Some(buffer)
 }
@@ -130,7 +160,7 @@ pub fn disk_device_priority() -> Vec<DiskDevice> {
             return vec![DiskDevice {
                 handle: esp_handle,
                 // Support both a copy of livedisk.iso and a standalone redoxfs partition
-                partition_offset: if &buffer[512..520] == b"EFI PART" {
+                partition_offset: if buffer.len() >= 520 && &buffer[512..520] == b"EFI PART" {
                     //TODO: get block from partition table
                     2 * crate::MIBI as u64
                 } else {