From 80f75fb758f81970a18e7a0ee503a974cc67e7e0 Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: Wed, 4 May 2022 13:58:37 +0200
Subject: [PATCH] qemu_fd: Add validation before transferring file descriptors
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Add validation to the transfer step to make the adding step more simple
for easier cleanup paths.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
---
 src/qemu/qemu_fd.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/src/qemu/qemu_fd.c b/src/qemu/qemu_fd.c
index 1af8932bdd..284e77ba2b 100644
--- a/src/qemu/qemu_fd.c
+++ b/src/qemu/qemu_fd.c
@@ -65,6 +65,30 @@ qemuFDPassFree(qemuFDPass *fdpass)
 }
 
 
+static int
+qemuFDPassValidate(qemuFDPass *fdpass)
+{
+    size_t i;
+
+    if (!fdpass->useFDSet &&
+        fdpass->nfds > 1) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("direct FD passing supports only 1 file descriptor"));
+        return -1;
+    }
+
+    for (i = 0; i < fdpass->nfds; i++) {
+        if (fdpass->fds[i].fd < 0) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                           _("invalid file descriptor"));
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+
 /**
  * qemuFDPassNew:
  * @prefix: prefix used for naming the passed FDs
@@ -186,6 +210,9 @@ qemuFDPassTransferCommand(qemuFDPass *fdpass,
     if (!fdpass)
         return 0;
 
+    if (qemuFDPassValidate(fdpass) < 0)
+        return -1;
+
     for (i = 0; i < fdpass->nfds; i++) {
         virCommandPassFD(cmd, fdpass->fds[i].fd, VIR_COMMAND_PASS_FD_CLOSE_PARENT);
 
@@ -229,6 +256,9 @@ qemuFDPassTransferMonitor(qemuFDPass *fdpass,
     if (!fdpass)
         return 0;
 
+    if (qemuFDPassValidate(fdpass) < 0)
+        return -1;
+
     for (i = 0; i < fdpass->nfds; i++) {
         if (fdpass->useFDSet) {
             qemuMonitorAddFdInfo fdsetinfo;
@@ -274,6 +304,9 @@ qemuFDPassTransferMonitorFake(qemuFDPass *fdpass)
     if (!fdpass)
         return 0;
 
+    if (qemuFDPassValidate(fdpass) < 0)
+        return -1;
+
     if (fdpass->useFDSet) {
         fdpass->path = g_strdup_printf("/dev/fdset/monitor-fake");
     } else {
-- 
2.47.2