From 94447aeab3d20400680f624e4b84e7b6fc0aae0b Mon Sep 17 00:00:00 2001 From: Sam Balana Date: Fri, 7 Aug 2020 15:05:13 -0700 Subject: Fix panic during Address Resolution of neighbor entry created by NS When a Neighbor Solicitation is received, a neighbor entry is created with the remote host's link layer address, but without a link layer address resolver. If the host decides to send a packet addressed to the IP address of that neighbor entry, Address Resolution starts with a nil pointer to the link layer address resolver. This causes the netstack to panic and crash. This change ensures that when a packet is sent in that situation, the link layer address resolver will be set before Address Resolution begins. Tests: pkg/tcpip/stack:stack_test + TestEntryUnknownToStaleToProbeToReachable - TestNeighborCacheEntryNoLinkAddress Updates #1889 Updates #1894 Updates #1895 Updates #1947 Updates #1948 Updates #1949 Updates #1950 PiperOrigin-RevId: 325516471 --- pkg/tcpip/stack/nud.go | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'pkg/tcpip/stack/nud.go') diff --git a/pkg/tcpip/stack/nud.go b/pkg/tcpip/stack/nud.go index f848d50ad..e1ec15487 100644 --- a/pkg/tcpip/stack/nud.go +++ b/pkg/tcpip/stack/nud.go @@ -177,7 +177,7 @@ type NUDHandler interface { // Neighbor Solicitation for ARP or NDP, respectively). Validation of the // probe needs to be performed before calling this function since the // Neighbor Cache doesn't have access to view the NIC's assigned addresses. - HandleProbe(remoteAddr, localAddr tcpip.Address, protocol tcpip.NetworkProtocolNumber, remoteLinkAddr tcpip.LinkAddress) + HandleProbe(remoteAddr, localAddr tcpip.Address, protocol tcpip.NetworkProtocolNumber, remoteLinkAddr tcpip.LinkAddress, linkRes LinkAddressResolver) // HandleConfirmation processes an incoming neighbor confirmation (e.g. ARP // reply or Neighbor Advertisement for ARP or NDP, respectively). -- cgit v1.2.3