Received-SPF: pass (google.com: domain of linux-kernel+bounces-71155-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
From: kovalev@altlinux.org
To: linux-kernel@vger.kernel.org
Cc: keescook@chromium.org,
	gregkh@linuxfoundation.org,
	bryantan@vmware.com,
	vdasa@vmware.com,
	pv-drivers@vmware.com,
	arnd@arndb.de,
	harshit.m.mogalapalli@oracle.com,
	nickel@altlinux.org,
	oficerovas@altlinux.org,
	dutyrok@altlinux.org,
	kovalev@altlinux.org
Subject: [PATCH] VMCI: Fix possible memcpy() run-time warning in vmci_datagram_invoke_guest_handler()
Date: Mon, 19 Feb 2024 13:53:15 +0300
Message-Id: <20240219105315.76955-1-kovalev@altlinux.org>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

From: Vasiliy Kovalev <kovalev@altlinux.org>

The changes are similar to those given in the commit 19b070fefd0d
("VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()").

Fix filling of the msg and msg_payload in dg_info struct, which prevents a
possible "detected field-spanning write" of memcpy warning that is issued
by the tracking mechanism __fortify_memcpy_chk.

Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
---
 drivers/misc/vmw_vmci/vmci_datagram.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/vmw_vmci/vmci_datagram.c b/drivers/misc/vmw_vmci/vmci_datagram.c
index d1d8224c8800c4..a0ad1f3a69f7e9 100644
--- a/drivers/misc/vmw_vmci/vmci_datagram.c
+++ b/drivers/misc/vmw_vmci/vmci_datagram.c
@@ -378,7 +378,8 @@ int vmci_datagram_invoke_guest_handler(struct vmci_datagram *dg)
 
 		dg_info->in_dg_host_queue = false;
 		dg_info->entry = dst_entry;
-		memcpy(&dg_info->msg, dg, VMCI_DG_SIZE(dg));
+		dg_info->msg = *dg;
+		memcpy(&dg_info->msg_payload, dg + 1, dg->payload_size);
 
 		INIT_WORK(&dg_info->work, dg_delayed_dispatch);
 		schedule_work(&dg_info->work);
-- 
2.33.8