From 57c5647d98c2a026de8b681159cb188ca0439ef8 Mon Sep 17 00:00:00 2001
From: akallabeth <akallabeth@posteo.net>
Date: Sun, 11 Jan 2026 09:03:57 +0100
Subject: [PATCH] [utils,smartcard] add length validity checks

in smartcard_unpack_set_attrib_call input length validity checks were
missing.
---
 libfreerdp/utils/smartcard_pack.c | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

Index: FreeRDP-3.10.3/libfreerdp/utils/smartcard_pack.c
===================================================================
--- FreeRDP-3.10.3.orig/libfreerdp/utils/smartcard_pack.c
+++ FreeRDP-3.10.3/libfreerdp/utils/smartcard_pack.c
@@ -97,8 +97,8 @@ static BOOL smartcard_ndr_pointer_read_(
 	return TRUE;
 }
 
-static LONG smartcard_ndr_read(wStream* s, BYTE** data, size_t min, size_t elementSize,
-                               ndr_ptr_t type)
+static LONG smartcard_ndr_read_ex(wStream* s, BYTE** data, size_t min,
+                                  size_t elementSize, ndr_ptr_t type, size_t* plen)
 {
 	size_t len = 0;
 	size_t offset = 0;
@@ -107,6 +107,9 @@ static LONG smartcard_ndr_read(wStream*
 	size_t required = 0;
 
 	*data = NULL;
+	if (plen)
+		*plen = 0;
+
 	switch (type)
 	{
 		case NDR_PTR_FULL:
@@ -181,11 +184,20 @@ static LONG smartcard_ndr_read(wStream*
 	if (!r)
 		return SCARD_E_NO_MEMORY;
 	Stream_Read(s, r, len);
-	smartcard_unpack_read_size_align(s, len, 4);
+	const LONG pad = smartcard_unpack_read_size_align(s, len, 4);
+	len += (size_t)pad;
 	*data = r;
+	if (plen)
+		*plen = len;
 	return STATUS_SUCCESS;
 }
 
+static LONG smartcard_ndr_read(wStream* s, BYTE** data, size_t min, size_t elementSize,
+                               ndr_ptr_t type)
+{
+	return smartcard_ndr_read_ex(s, data, min, elementSize, type, NULL);
+}
+
 static BOOL smartcard_ndr_pointer_write(wStream* s, UINT32* index, DWORD length)
 {
 	const UINT32 ndrPtr = 0x20000 + (*index) * 4;
@@ -3207,14 +3219,17 @@ LONG smartcard_unpack_set_attrib_call(wS
 
 	if (ndrPtr)
 	{
-		// TODO: call->cbAttrLen was larger than the pointer value.
-		// TODO: Maybe need to refine the checks?
-		status = smartcard_ndr_read(s, &call->pbAttr, 0, 1, NDR_PTR_SIMPLE);
-		if (status != SCARD_S_SUCCESS)
-			return status;
-	}
-	smartcard_trace_set_attrib_call(call);
-	return SCARD_S_SUCCESS;
+        size_t len = 0;
+        status = smartcard_ndr_read_ex(s, &call->pbAttr, 0, 1, NDR_PTR_SIMPLE, &len);
+        if (status != SCARD_S_SUCCESS)
+            return status;
+        if (call->cbAttrLen > len)
+            call->cbAttrLen = WINPR_ASSERTING_INT_CAST(DWORD, len);
+    }
+    else
+        call->cbAttrLen = 0;
+    smartcard_trace_set_attrib_call(call);
+    return SCARD_S_SUCCESS;
 }
 
 LONG smartcard_unpack_locate_cards_by_atr_w_call(wStream* s, LocateCardsByATRW_Call* call)