| Message ID | 0bf24707358ef15ab42b44037da4dc46e3e63acb.1550684182.git.pabeni@redhat.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | ipv6: route: enforce RCU protection for fib6_info->from | expand |
On 2/21/19 5:19 AM, Paolo Abeni wrote: > We need a RCU critical section around rt6_info->from deference, and > proper annotation. > > Fixes: 4ed591c8ab44 ("net/ipv6: Allow onlink routes to have a device mismatch if it is the default route") > Signed-off-by: Paolo Abeni <pabeni@redhat.com> > --- > net/ipv6/route.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > Reviewed-by: David Ahern <dsahern@gmail.com> Thanks for the fixing.
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 1597a3746b40..047c47224dba 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2754,20 +2754,24 @@ static int ip6_route_check_nh_onlink(struct net *net, u32 tbid = l3mdev_fib_table(dev) ? : RT_TABLE_MAIN; const struct in6_addr *gw_addr = &cfg->fc_gateway; u32 flags = RTF_LOCAL | RTF_ANYCAST | RTF_REJECT; + struct fib6_info *from; struct rt6_info *grt; int err; err = 0; grt = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0); if (grt) { + rcu_read_lock(); + from = rcu_dereference(grt->from); if (!grt->dst.error && /* ignore match if it is the default route */ - grt->from && !ipv6_addr_any(&grt->from->fib6_dst.addr) && + from && !ipv6_addr_any(&from->fib6_dst.addr) && (grt->rt6i_flags & flags || dev != grt->dst.dev)) { NL_SET_ERR_MSG(extack, "Nexthop has invalid gateway or device mismatch"); err = -EINVAL; } + rcu_read_unlock(); ip6_rt_put(grt); }
We need a RCU critical section around rt6_info->from deference, and proper annotation. Fixes: 4ed591c8ab44 ("net/ipv6: Allow onlink routes to have a device mismatch if it is the default route") Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- net/ipv6/route.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)