package/network/services/ppp/patches/207-lcp_mtu_max.patch

   1 pppd: Cap MTU to the user configured value
   2
   3 This patchs caps the calculated MTU value in lcp.c to the user specified "mru"
   4 option value. Without this patch pppd would advertise a different MTU value
   5 compared to what is set on the local interface in some cases.
   6
   7 Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>
   8
   9 --- a/pppd/lcp.c
  10 +++ b/pppd/lcp.c
  11 @@ -1904,12 +1904,12 @@ lcp_up(f)
  12       * the interface MTU is set to the lowest of that, the
  13       * MTU we want to use, and our link MRU.
  14       */
  15 -    mtu = ho->neg_mru? ho->mru: PPP_MRU;
  16 +    mtu = MIN(ho->neg_mru? ho->mru: PPP_MRU, ao->mru);
  17      mru = go->neg_mru? MAX(wo->mru, go->mru): PPP_MRU;
  18  #ifdef HAVE_MULTILINK
  19      if (!(multilink && go->neg_mrru && ho->neg_mrru))
  20  #endif /* HAVE_MULTILINK */
  21 -       netif_set_mtu(f->unit, MIN(MIN(mtu, mru), ao->mru));
  22 +       netif_set_mtu(f->unit, MIN(mtu, mru));
  23      ppp_send_config(f->unit, mtu,
  24                     (ho->neg_asyncmap? ho->asyncmap: 0xffffffff),
  25                     ho->neg_pcompression, ho->neg_accompression);