fix --join for sandboxes with xdg-dbuss-proxy

1 files changed, 7 insertions, 2 deletions

diff --git a/src/firejail/util.c b/src/firejail/util.c
index d65ac0071..9f878611a 100644
--- a/src/firejail/util.c
+++ b/src/firejail/util.c
@@ -647,8 +647,13 @@ int find_child(pid_t parent, pid_t *child) {
                                         fprintf(stderr, "Error: cannot read /proc file\n");
                                         exit(1);
                                 }
-                                if (parent == atoi(ptr))
-                                        *child = pid;
+                                if (parent == atoi(ptr)) {
+                                        // we don't want /usr/bin/xdg-dbus-proxy!
+                                        char *cmdline = pid_proc_cmdline(pid);
+                                        if (strncmp(cmdline, XDG_DBUS_PROXY_PATH, strlen(XDG_DBUS_PROXY_PATH)) != 0)
+                                                *child = pid;
+                                        free(cmdline);
+                                }
                                 break;            // stop reading the file
                         }
                 }