SIOCSIFNAME: Do nothing if we're not actually changing

Instead of throwing EEXIST, just succeed if the name isn't actually
changing. We don't need to trigger departure or any of that because there's
no change from consumers' perspective.

PR:		240539
Reviewed by:	brooks
MFC after:	5 days
Differential Revision:	https://reviews.freebsd.org/D21618

diff --git a/sys/net/if.c b/sys/net/if.c
index d1513d2a32d781da4e93bf62054a5bd72c2b359c..cfd0c20658884da38ebfe906e986c5f484a9c5ab 100644 (file)
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -2716,6 +2716,8 @@ ifhwioctl(u_long cmd, struct ifnet *ifp, caddr_t data, struct thread *td)
                        if (strlen(new_name) == IFNAMSIZ-1)
                                return (EINVAL);
                }
+               if (strcmp(new_name, ifp->if_xname) == 0)
+                       break;
                if (ifunit(new_name) != NULL)
                        return (EEXIST);