From 3af57e3483dc12e87e4d2b5d53a2b8e17be2b00d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marco=20Trevisan=20=28Trevi=C3=B1o=29?= <mail@3v1n0.net>
Date: Wed, 17 Jun 2026 18:41:49 +0200
Subject: [PATCH] secugen: Check transfers have a minimal lengths

---
 libfprint/drivers/secugen.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/libfprint/drivers/secugen.c b/libfprint/drivers/secugen.c
index 36246010..e5d65ff3 100644
--- a/libfprint/drivers/secugen.c
+++ b/libfprint/drivers/secugen.c
@@ -526,6 +526,13 @@ init_i2c_readback_cb (FpiUsbTransfer *transfer,
       return;
     }
 
+  if (transfer->actual_length < 1)
+    {
+      fpi_ssm_mark_failed (transfer->ssm,
+                           fpi_device_error_new (FP_DEVICE_ERROR_PROTO));
+      return;
+    }
+
   self->last_reg_rd = transfer->buffer[0];
   self->init_reg_idx++;
 
@@ -555,6 +562,13 @@ init_late_readback_cb (FpiUsbTransfer *transfer,
       return;
     }
 
+  if (transfer->actual_length < 1)
+    {
+      fpi_ssm_mark_failed (transfer->ssm,
+                           fpi_device_error_new (FP_DEVICE_ERROR_PROTO));
+      return;
+    }
+
   self->last_reg_rd = transfer->buffer[0];
   self->init_reg_idx++;
 
@@ -584,6 +598,13 @@ init_window_readback_cb (FpiUsbTransfer *transfer,
       return;
     }
 
+  if (transfer->actual_length < 1)
+    {
+      fpi_ssm_mark_failed (transfer->ssm,
+                           fpi_device_error_new (FP_DEVICE_ERROR_PROTO));
+      return;
+    }
+
   self->last_reg_rd = transfer->buffer[0];
   self->init_reg_idx++;
 
@@ -740,6 +761,13 @@ init_frame_readback_cb (FpiUsbTransfer *transfer,
       return;
     }
 
+  if (transfer->actual_length < 1)
+    {
+      fpi_ssm_mark_failed (transfer->ssm,
+                           fpi_device_error_new (FP_DEVICE_ERROR_PROTO));
+      return;
+    }
+
   self->last_reg_rd = transfer->buffer[0];
   self->init_reg_idx++;