viced: Correctly update addrs on alt addr probe
authorAndrew Deason <adeason@sinenomine.net>
Fri, 17 Feb 2012 19:14:31 +0000 (13:14 -0600)
committerDerrick Brashear <shadow@dementix.org>
Mon, 20 Feb 2012 21:14:57 +0000 (13:14 -0800)
The functions MultiBreakCallBackAlternateAddress_r and
MultiProbeAlternateAddress_r try to find a valid address in a host's
interface list of addrs. If they find one, they update host->host and
host->port. However, they do so just by changing those fields directly
and by calling h_DeleteHostFromAddrHashTable_r and
h_AddHostToAddrHashTable_r. This leaves the old host->host, host->port
on the interface list, and leaves it marked as 'valid'. Similarly, the
new host and port may still be marked as not 'valid'.

This can result in the host being on the addr hash table via an
address that is not on the host's interface list. After the above
situation occurs, we may call

  removeInterfaceAddr_r(host, host->host, host->port);

and then update host->host and host->port, which happens in a variety
of places. Since host->host, host->port is not marked as valid in the
interface list, it is not removed from the addr hash table, but it is
removed from the interface list. Eventually, this can cause the host
to be referenced from the addr hash table even after it has been
freed.

Since this can result in hash table entries pointing to the 'wrong'
host, this can result in FileLog messages such as:

Sun Feb  5 03:16:35 2012 Removing address that does not belong to host 0xdeadbeefdead (1.2.3.4:7001).

And bogus instances of the message:

Sun Feb  5 03:16:36 2012 CB: new identity for host 0xdeadbeefdead (1.2.3.4:7001), deleting(1 baadcafe 12345678-9abc-def0-12-34-456789abcdef fedcba98-76543210f-ed-cb-a9876543210f)

To fix this, make MultiBreakCallBackAlternateAddress_r and
MultiProbeAlternateAddress_r update the address list the same way as
all of the code in host.c does; by adding the new address with
addInterfaceAddr_r, removing it with removeInterfaceAddr_r, and
updating host->host and host->port.

Change-Id: I0a95e0186c03c1831c4df86daae901bf2462da0e
Reviewed-on: http://gerrit.openafs.org/6727
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Reviewed-by: Alistair Ferguson <alistair.ferguson@mac.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>

src/viced/callback.c

index a4fb613..b6e3373 100644 (file)
@@ -3004,10 +3004,12 @@ MultiBreakCallBackAlternateAddress_r(struct host *host,
            if (host->callback_rxcon)
                rx_DestroyConnection(host->callback_rxcon);
            host->callback_rxcon = conns[multi_i];
-            h_DeleteHostFromAddrHashTable_r(host->host, host->port, host);
+           /* add then remove */
+           addInterfaceAddr_r(host, interfaces[multi_i].addr,
+                                    interfaces[multi_i].port);
+           removeInterfaceAddr_r(host, host->host, host->port);
            host->host = interfaces[multi_i].addr;
            host->port = interfaces[multi_i].port;
-            h_AddHostToAddrHashTable_r(host->host, host->port, host);
            connSuccess = conns[multi_i];
            rx_SetConnDeadTime(host->callback_rxcon, 50);
            rx_SetConnHardDeadTime(host->callback_rxcon, AFS_HARDDEADTIME);
@@ -3100,10 +3102,12 @@ MultiProbeAlternateAddress_r(struct host *host)
            if (host->callback_rxcon)
                rx_DestroyConnection(host->callback_rxcon);
            host->callback_rxcon = conns[multi_i];
-            h_DeleteHostFromAddrHashTable_r(host->host, host->port, host);
+           /* add then remove */
+           addInterfaceAddr_r(host, interfaces[multi_i].addr,
+                                    interfaces[multi_i].port);
+           removeInterfaceAddr_r(host, host->host, host->port);
            host->host = interfaces[multi_i].addr;
            host->port = interfaces[multi_i].port;
-            h_AddHostToAddrHashTable_r(host->host, host->port, host);
            connSuccess = conns[multi_i];
            rx_SetConnDeadTime(host->callback_rxcon, 50);
            rx_SetConnHardDeadTime(host->callback_rxcon, AFS_HARDDEADTIME);