core: extra paranoia when deserializing kdbus fd

diff --git a/src/core/manager.c b/src/core/manager.c
index badf19e9548c91b4f801169d8244e97f406f200f..19493861ecdbb0566bac615d53d91650ca88084f 100644 (file)
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -2172,7 +2172,7 @@ int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
                 } else if (startswith(l, "kdbus-fd=")) {
                         int fd;
 
-                        if (safe_atoi(l + 9, &fd) < 0 || !fdset_contains(fds, fd))
+                        if (safe_atoi(l + 9, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
                                 log_debug("Failed to parse kdbus fd: %s", l + 9);
                         else {
                                 if (m->kdbus_fd >= 0)