Bind loopback subnets' lifetime to perm address

The lifetime of addreses in a loopback interface's associated subnets
should be bound to their respective permanent addresses.

This change also fixes a race when the stack attempts to get an IPv4
rereferencedNetworkEndpoint for an address in an associated subnet on
a loopback interface. Before this change, the stack would only check
if an IPv4 address is contained in an associated subnet while holding
a read lock but wouldn't do this same check after releasing the read
lock for a write lock to create a temporary address. This may cause
the stack to bind the lifetime of the address to a new (temporary)
endpoint instead of the associated subnet's permanent address.

Test: integration_test.TestLoopbackSubnetLifetimeBoundToAddr
PiperOrigin-RevId: 332094719

0 files changed, 0 insertions, 0 deletions