| Message ID | 56634F31.3000609@shemyak.com |
|---|---|
| State | Rejected, archived |
| Delegated to: | David Miller |
| Headers | show |
On Sat, Dec 5, 2015 at 12:55 PM, Konstantin Shemyak <konstantin@shemyak.com> wrote: > The DF bit on IPv4 GRE tunnels with fixed TTL is enforced in order > to prevent networking loops. This was the original behavior of GRE > tunnels, lost in the refactoring. > > Signed-off-by: Konstantin Shemyak <konstantin@shemyak.com> > --- > net/ipv4/ip_gre.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c > index 6145214..485bf27 100644 > --- a/net/ipv4/ip_gre.c > +++ b/net/ipv4/ip_gre.c > @@ -679,6 +679,10 @@ static int ipgre_tunnel_ioctl(struct net_device *dev, > ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))) > return -EINVAL; > } > + > + if (p.iph.ttl) > + p.iph.frag_off |= htons(IP_DF); > + Same code already exist in ip_tunnel_ioctl() which is common function for IP based tunnel modules. Why does that not work? > p.i_flags = gre_flags_to_tnl_flags(p.i_flags); > p.o_flags = gre_flags_to_tnl_flags(p.o_flags); > > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Konstantin Shemyak <konstantin@shemyak.com> Date: Sat, 5 Dec 2015 22:55:13 +0200 > The DF bit on IPv4 GRE tunnels with fixed TTL is enforced in order > to prevent networking loops. This was the original behavior of GRE > tunnels, lost in the refactoring. > > Signed-off-by: Konstantin Shemyak <konstantin@shemyak.com> Like Pravin said, ip_tunnel_ioctl() does this already, the code you are adding is superfluous. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 6145214..485bf27 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -679,6 +679,10 @@ static int ipgre_tunnel_ioctl(struct net_device *dev, ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))) return -EINVAL; } + + if (p.iph.ttl) + p.iph.frag_off |= htons(IP_DF); + p.i_flags = gre_flags_to_tnl_flags(p.i_flags); p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
The DF bit on IPv4 GRE tunnels with fixed TTL is enforced in order to prevent networking loops. This was the original behavior of GRE tunnels, lost in the refactoring. Signed-off-by: Konstantin Shemyak <konstantin@shemyak.com> --- net/ipv4/ip_gre.c | 4 ++++ 1 file changed, 4 insertions(+)