diff options
-rw-r--r-- | services/net/java/android/net/ip/IpManager.java | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/services/net/java/android/net/ip/IpManager.java b/services/net/java/android/net/ip/IpManager.java index de2c0c6a268b..d0ab606f039e 100644 --- a/services/net/java/android/net/ip/IpManager.java +++ b/services/net/java/android/net/ip/IpManager.java @@ -657,7 +657,7 @@ public class IpManager extends StateMachine { // object that is a correct and complete assessment of what changed, taking // account of the asymmetries described in the comments in this function. // Then switch to using it everywhere (IpReachabilityMonitor, etc.). - private static ProvisioningChange compareProvisioning( + private ProvisioningChange compareProvisioning( LinkProperties oldLp, LinkProperties newLp) { ProvisioningChange delta; @@ -688,6 +688,21 @@ public class IpManager extends StateMachine { final boolean lostIPv4Address = oldLp.hasIPv4Address() && !newLp.hasIPv4Address(); final boolean lostIPv6Router = oldLp.hasIPv6DefaultRoute() && !newLp.hasIPv6DefaultRoute(); + // If bad wifi avoidance is disabled, then ignore IPv6 loss of + // provisioning. Otherwise, when a hotspot that loses Internet + // access sends out a 0-lifetime RA to its clients, the clients + // will disconnect and then reconnect, avoiding the bad hotspot, + // instead of getting stuck on the bad hotspot. http://b/31827713 . + // + // This is incorrect because if the hotspot then regains Internet + // access with a different prefix, TCP connections on the + // deprecated addresses will remain stuck. + // + // Note that we can still be disconnected by IpReachabilityMonitor + // if the IPv6 default gateway (but not the IPv6 DNS servers; see + // accompanying code in IpReachabilityMonitor) is unreachable. + final boolean ignoreIPv6ProvisioningLoss = !mAvoidBadWifiTracker.currentValue(); + // Additionally: // // Partial configurations (e.g., only an IPv4 address with no DNS @@ -700,7 +715,7 @@ public class IpManager extends StateMachine { // Because on such a network isProvisioned() will always return false, // delta will never be LOST_PROVISIONING. So check for loss of // provisioning here too. - if (lostIPv4Address || lostIPv6) { + if (lostIPv4Address || (lostIPv6 && !ignoreIPv6ProvisioningLoss)) { delta = ProvisioningChange.LOST_PROVISIONING; } @@ -709,7 +724,7 @@ public class IpManager extends StateMachine { // If the previous link properties had a global IPv6 address and an // IPv6 default route then also consider the loss of that default route // to be a loss of provisioning. See b/27962810. - if (oldLp.hasGlobalIPv6Address() && lostIPv6Router) { + if (oldLp.hasGlobalIPv6Address() && (lostIPv6Router && !ignoreIPv6ProvisioningLoss)) { delta = ProvisioningChange.LOST_PROVISIONING; } |