| Message ID | 20181004213355.14899-18-dsahern@kernel.org |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | rtnetlink: Add support for rigid checking of data in dump request | expand |
On Thu, Oct 04, 2018 at 02:33:52PM -0700, David Ahern wrote: > From: David Ahern <dsahern@gmail.com> > > Update fib_nl_dumprule for strict data checking. If the flag is set, > the dump request is expected to have fib_rule_hdr struct as the header. > All elements of the struct are expected to be 0 and no attributes can > be appended. > > Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Christian Brauner <christian@brauner.io> > --- > net/core/fib_rules.c | 36 +++++++++++++++++++++++++++++++++++- > 1 file changed, 35 insertions(+), 1 deletion(-) > > diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c > index 0ff3953f64aa..e3cf50728d0a 100644 > --- a/net/core/fib_rules.c > +++ b/net/core/fib_rules.c > @@ -1063,13 +1063,47 @@ static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb, > return err; > } > > +static int fib_valid_dumprule(const struct nlmsghdr *nlh, > + struct netlink_ext_ack *extack) > +{ > + struct fib_rule_hdr *frh; > + > + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) { > + NL_SET_ERR_MSG(extack, "Invalid header"); > + return -EINVAL; > + } > + > + frh = nlmsg_data(nlh); > + if (frh->dst_len || frh->src_len || frh->tos || frh->table || > + frh->res1 || frh->res2 || frh->action || frh->flags) { > + NL_SET_ERR_MSG(extack, > + "Invalid values in header for dump request"); > + return -EINVAL; > + } > + > + if (nlh->nlmsg_len != nlmsg_msg_size(sizeof(*frh))) { > + NL_SET_ERR_MSG(extack, "Invalid data after header"); > + return -EINVAL; > + } > + > + return 0; > +} > + > static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb) > { > + const struct nlmsghdr *nlh = cb->nlh; > struct net *net = sock_net(skb->sk); > struct fib_rules_ops *ops; > int idx = 0, family; > > - family = rtnl_msg_family(cb->nlh); > + if (cb->strict_check) { > + int err = fib_valid_dumprule(nlh, cb->extack); > + > + if (err) > + return err; > + } > + > + family = rtnl_msg_family(nlh); > if (family != AF_UNSPEC) { > /* Protocol specific dump request */ > ops = lookup_rules_ops(net, family); > -- > 2.11.0 >
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 0ff3953f64aa..e3cf50728d0a 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -1063,13 +1063,47 @@ static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb, return err; } +static int fib_valid_dumprule(const struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct fib_rule_hdr *frh; + + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) { + NL_SET_ERR_MSG(extack, "Invalid header"); + return -EINVAL; + } + + frh = nlmsg_data(nlh); + if (frh->dst_len || frh->src_len || frh->tos || frh->table || + frh->res1 || frh->res2 || frh->action || frh->flags) { + NL_SET_ERR_MSG(extack, + "Invalid values in header for dump request"); + return -EINVAL; + } + + if (nlh->nlmsg_len != nlmsg_msg_size(sizeof(*frh))) { + NL_SET_ERR_MSG(extack, "Invalid data after header"); + return -EINVAL; + } + + return 0; +} + static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb) { + const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); struct fib_rules_ops *ops; int idx = 0, family; - family = rtnl_msg_family(cb->nlh); + if (cb->strict_check) { + int err = fib_valid_dumprule(nlh, cb->extack); + + if (err) + return err; + } + + family = rtnl_msg_family(nlh); if (family != AF_UNSPEC) { /* Protocol specific dump request */ ops = lookup_rules_ops(net, family);