--userns --uid: Only swtich user if neededreuse-namespaces

We don't want to switch user unless we have to because we might
not be in a trivial mapping, such as the outer userns in a devpts workaround
hack.

1 files changed, 2 insertions, 2 deletions

diff --git a/bubblewrap.c b/bubblewrap.c
index f1feb5e..8d0c5f7 100644
--- a/bubblewrap.c
+++ b/bubblewrap.c
@@ -811,10 +811,10 @@ switch_to_user_with_privs (void)
   /* If we switched to a new user namespace it may allow other uids/gids, so switch to the target one */
   if (opt_userns_fd != -1)
     {
-      if (setuid (opt_sandbox_uid) < 0)
+      if (opt_sandbox_uid != real_uid && setuid (opt_sandbox_uid) < 0)
         die_with_error ("unable to switch to uid %d", opt_sandbox_uid);
 
-      if (setgid (opt_sandbox_gid) < 0)
+      if (opt_sandbox_gid != real_gid && setgid (opt_sandbox_gid) < 0)
         die_with_error ("unable to switch to gid %d", opt_sandbox_gid);
     }