On Sun, 24 Jan 2021 at 17:26, David Ahern <dsah...@gmail.com> wrote: > > On 1/24/21 8:53 AM, Luca Boccassi wrote: > > Since NETLINK_GET_STRICT_CHK was enabled, the kernel rejects commands > > that pass a prefix length, eg: > > > > ip route get `1.0.0.0/1 > > Error: ipv4: Invalid values in header for route get request. > > ip route get 0.0.0.0/0 > > Error: ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4 > > Those are not the best responses from the kernel for the mask setting. I > should have been clearer about src and dst masks. > > > > > Since there's no point in setting a rtm_dst_len that we know is going > > to be rejected, just force it to the right value if it's passed on > > the command line. > > > > Bug-Debian: https://bugs.debian.org/944730 > > Reported-By: Clément 'wxcafé' Hertling <wxc...@wxcafe.net> > > Signed-off-by: Luca Boccassi <bl...@debian.org> > > --- > > As mentioned by David on: > > > > https://www.spinics.net/lists/netdev/msg624125.html > > > > ip/iproute.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/ip/iproute.c b/ip/iproute.c > > index ebb5f160..3646d531 100644 > > --- a/ip/iproute.c > > +++ b/ip/iproute.c > > @@ -2069,7 +2069,12 @@ static int iproute_get(int argc, char **argv) > > if (addr.bytelen) > > addattr_l(&req.n, sizeof(req), > > RTA_DST, &addr.data, addr.bytelen); > > - req.r.rtm_dst_len = addr.bitlen; > > + if (req.r.rtm_family == AF_INET) > > + req.r.rtm_dst_len = 32; > > + else if (req.r.rtm_family == AF_INET6) > > + req.r.rtm_dst_len = 128; > > + else > > + req.r.rtm_dst_len = addr.bitlen; > > address_found = true; > > } > > argc--; argv++; > > > > Since the kernel used to blindly ignore the mask, having iproute2 fix it > up seems acceptable. > > I think it would be good to educate the user about invalid settings as > well - get them to fix scripts and mind set.
Sent v2 with a warning print to stderr. Kind regards, Luca Boccassi
