libvncserver: check for invalid socket before FD_ISSET in httpd

A mere workaround/mitigation for when the socket is closed by another thread...
LibVNC · Aug 30, 2024 · 27617e1 · 27617e1
1 parent 06cff31
commit 27617e1
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/libvncserver/httpd.c b/src/libvncserver/httpd.c
@@ -203,7 +203,8 @@ rfbHttpCheckFds(rfbScreenInfoPtr rfbScreen)
 	httpProcessInput(rfbScreen);
     }
 
-    if (FD_ISSET(rfbScreen->httpListenSock, &fds) || FD_ISSET(rfbScreen->httpListen6Sock, &fds)) {
+    if ((rfbScreen->httpListenSock != RFB_INVALID_SOCKET && FD_ISSET(rfbScreen->httpListenSock, &fds))
+        || (rfbScreen->httpListen6Sock != RFB_INVALID_SOCKET && FD_ISSET(rfbScreen->httpListen6Sock, &fds))) {
 	if (rfbScreen->httpSock != RFB_INVALID_SOCKET) rfbCloseSocket(rfbScreen->httpSock);
 
 	if(FD_ISSET(rfbScreen->httpListenSock, &fds)) {