diff options
Diffstat (limited to 'pkg/tcpip/stack/iptables_targets.go')
| -rw-r--r-- | pkg/tcpip/stack/iptables_targets.go | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/pkg/tcpip/stack/iptables_targets.go b/pkg/tcpip/stack/iptables_targets.go index 7b4543caf..8be61f4b1 100644 --- a/pkg/tcpip/stack/iptables_targets.go +++ b/pkg/tcpip/stack/iptables_targets.go @@ -96,9 +96,12 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { newPkt := pkt.Clone() // Set network header. - headerView := newPkt.Data.First() + headerView, ok := newPkt.Data.PullUp(header.IPv4MinimumSize) + if !ok { + return RuleDrop, 0 + } netHeader := header.IPv4(headerView) - newPkt.NetworkHeader = headerView[:header.IPv4MinimumSize] + newPkt.NetworkHeader = headerView hlen := int(netHeader.HeaderLength()) tlen := int(netHeader.TotalLength()) @@ -117,10 +120,14 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { if newPkt.TransportHeader != nil { udpHeader = header.UDP(newPkt.TransportHeader) } else { - if len(pkt.Data.First()) < header.UDPMinimumSize { + if pkt.Data.Size() < header.UDPMinimumSize { + return RuleDrop, 0 + } + hdr, ok := newPkt.Data.PullUp(header.UDPMinimumSize) + if !ok { return RuleDrop, 0 } - udpHeader = header.UDP(newPkt.Data.First()) + udpHeader = header.UDP(hdr) } udpHeader.SetDestinationPort(rt.MinPort) case header.TCPProtocolNumber: @@ -128,10 +135,14 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { if newPkt.TransportHeader != nil { tcpHeader = header.TCP(newPkt.TransportHeader) } else { - if len(pkt.Data.First()) < header.TCPMinimumSize { + if pkt.Data.Size() < header.TCPMinimumSize { return RuleDrop, 0 } - tcpHeader = header.TCP(newPkt.TransportHeader) + hdr, ok := newPkt.Data.PullUp(header.TCPMinimumSize) + if !ok { + return RuleDrop, 0 + } + tcpHeader = header.TCP(hdr) } // TODO(gvisor.dev/issue/170): Need to recompute checksum // and implement nat connection tracking to support TCP. |