File hw-pvrdma-Protect-against-buggy-or-malic.patch of Package qemu.30221

From: Li Zhang <lizhang@suse.de>
Date: Thu, 10 Aug 2023 16:45:02 +0200
Subject: hw/pvrdma: Protect against buggy or malicious guest driver

Guest driver might execute HW commands when shared buffers are not yet
allocated.
This could happen on purpose (malicious guest) or because of some other
guest/host address mapping error.
We need to protect againts such case.

Fixes: CVE-2022-1050

Reported-by: Raven <wxhusst@gmail.com>
Signed-off-by: Yuval Shaia <yuval.shaia.ml@gmail.com>
Message-Id: <20220403095234.2210-1-yuval.shaia.ml@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Li Zhang <lizhang@suse.de>
---
 hw/rdma/vmw/pvrdma_cmd.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/hw/rdma/vmw/pvrdma_cmd.c b/hw/rdma/vmw/pvrdma_cmd.c
index 1df0b256fa88e092767e18c471cb..1e23b34410fdbee4d466eac546c3 100644
--- a/hw/rdma/vmw/pvrdma_cmd.c
+++ b/hw/rdma/vmw/pvrdma_cmd.c
@@ -796,6 +796,12 @@ int pvrdma_exec_cmd(PVRDMADev *dev)
 
     dsr_info = &dev->dsr_info;
 
+    if (!dsr_info->dsr) {
+            /* Buggy or malicious guest driver */
+            rdma_error_report("Exec command without dsr, req or rsp buffers");
+            goto out;
+    }
+
     if (dsr_info->req->hdr.cmd >= sizeof(cmd_handlers) /
                       sizeof(struct cmd_handler)) {
         rdma_error_report("Unsupported command");