Evan Wildenhain

Loopback LinkEndpoint teardown can race with WritePackets

4

### Description Loopback LinkEndpoints are usually nested within an Ethernet endpoint when added to a gVisor Stack (this is true in [all non-test occurrences of loopback.New()](https://cs.opensource.google/search?q=loopback.New&sq=&ss=gvisor%2Fgvisor) in the gVisor repo)....

Define SO_BINDTOIFINDEX on Fuchsia

3

Fuchsia supports SO_BINDTOIFINDEX as of API level 20: https://cs.opensource.google/fuchsia/fuchsia/+/main:sdk/lib/zxio/socket.cc;l=755;drc=b03121152bf13fb8898a95b58d952c95ee73cd0c