From f66a7e2e482f6dbcf171018a60e6807d5a66a6ba Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Mon, 6 Jan 2020 00:51:43 +0100
Subject: [PATCH] [NTOS:KE:X64] Zero out the context in KiDispatchException

---
 ntoskrnl/ke/amd64/except.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/ntoskrnl/ke/amd64/except.c b/ntoskrnl/ke/amd64/except.c
index 23ff7e016a9..40b01064d84 100644
--- a/ntoskrnl/ke/amd64/except.c
+++ b/ntoskrnl/ke/amd64/except.c
@@ -245,10 +245,13 @@ KiDispatchException(IN PEXCEPTION_RECORD ExceptionRecord,
     /* Increase number of Exception Dispatches */
     KeGetCurrentPrcb()->KeExceptionDispatchCount++;
 
+    /* Zero out the context to avoid leaking kernel stack memor to user mode */
+    RtlZeroMemory(&Context, sizeof(Context));
+
     /* Set the context flags */
     Context.ContextFlags = CONTEXT_ALL;
 
-    /* Get a Context */
+    /* Get the Context from the trap and exception frame */
     KeTrapFrameToContext(TrapFrame, ExceptionFrame, &Context);
 
     /* Look at our exception code */