From 91a743bd021a262af61c79cc35f0b634b2fcf3ad Mon Sep 17 00:00:00 2001
From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Date: Fri, 1 Nov 2024 13:39:09 +0000
Subject: [PATCH] hw/cxl: Check input includes at least the header in
cmd_features_set_feature()
A buggy guest might write an insufficiently large message.
Check the header is present. Whilst zero data after the header is very
odd it will just result in failure to copy any data.
Reported-by: Esifiel <esifiel@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20241101133917.27634-3-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
hw/cxl/cxl-mailbox-utils.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
index 17924410dd..e63140aefe 100644
--- a/hw/cxl/cxl-mailbox-utils.c
+++ b/hw/cxl/cxl-mailbox-utils.c
@@ -1238,6 +1238,9 @@ static CXLRetCode cmd_features_set_feature(const struct cxl_cmd *cmd,
CXLType3Dev *ct3d;
uint16_t count;
+ if (len_in < sizeof(*hdr)) {
+ return CXL_MBOX_INVALID_PAYLOAD_LENGTH;
+ }
if (!object_dynamic_cast(OBJECT(cci->d), TYPE_CXL_TYPE3)) {
return CXL_MBOX_UNSUPPORTED;