BMC/Intel-BMC/linux.git/net/tipc/name_table.h, branch dev-4.17

tipc: fix unbalanced reference counter

2018-04-13T01:46:10+00:00

When a topology subscription is created, we may encounter (or KASAN may provoke) a failure to create a corresponding service instance in the binding table. Instead of letting the tipc_nametbl_subscribe() report the failure back to the caller, the function just makes a warning printout and returns, without incrementing the subscription reference counter as expected by the caller. This makes the caller believe that the subscription was successful, so it will at a later moment try to unsubscribe the item. This involves a sub_put() call. Since the reference counter never was incremented in the first place, we get a premature delete of the subscription item, followed by a "use-after-free" warning. We fix this by adding a return value to tipc_nametbl_subscribe() and make the caller aware of the failure to subscribe. This bug seems to always have been around, but this fix only applies back to the commit shown below. Given the low risk of this happening we believe this to be sufficient. Fixes: commit 218527fe27ad ("tipc: replace name table service range array with rb tree") Reported-by: syzbot+aa245f26d42b8305d157@syzkaller.appspotmail.com Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: permit overlapping service ranges in name table

2018-04-01T02:19:52+00:00

With the new RB tree structure for service ranges it becomes possible to solve an old problem; - we can now allow overlapping service ranges in the table. When inserting a new service range to the tree, we use 'lower' as primary key, and when necessary 'upper' as secondary key. Since there may now be multiple service ranges matching an indicated 'lower' value, we must also add the 'upper' value to the functions used for removing publications, so that the correct, corresponding range item can be found. These changes guarantee that a well-formed publication/withdrawal item from a peer node never will be rejected, and make it possible to eliminate the problematic backlog functionality we currently have for handling such cases. Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: replace name table service range array with rb tree

2018-04-01T02:19:52+00:00

The current design of the binding table has an unnecessary memory consuming and complex data structure. It aggregates the service range items into an array, which is expanded by a factor two every time it becomes too small to hold a new item. Furthermore, the arrays never shrink when the number of ranges diminishes. We now replace this array with an RB tree that is holding the range items as tree nodes, each range directly holding a list of bindings. This, along with a few name changes, improves both readability and volume of the code, as well as reducing memory consumption and hopefully improving cache hit rate. Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: some name changes

2018-03-17T21:11:46+00:00

We rename some lists and fields in struct publication both to make the naming more consistent and to better reflect their roles. We also update the descriptions of those lists. node_list -> local_publ cluster_list -> all_publ pport_list -> binding_sock ref -> port There are no functional changes in this commit. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: merge two lists in struct publication

2018-03-17T21:11:46+00:00

The size of struct publication can be reduced further. Membership in lists 'nodesub_list' and 'local_list' is mutually exlusive, in that remote publications use the former and local publications the latter. We replace the two lists with one single, named 'binding_node' which reflects what it really is. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: remove zone_list member in struct publication

2018-03-17T21:11:46+00:00

As a further consequence of the previous commits, we can also remove the member 'zone_list 'in struct name_info and struct publication. Instead, we now let the member cluster_list take over the role a container of all publications of a given . We also remove the counters for the size of those lists, since they don't serve any purpose. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: remove zone publication list in name table

2018-03-17T21:11:46+00:00

As a consequence of the previous commit we nan now eliminate zone scope related lists in the name table. We start with name_table::publ_list[3], which can now be replaced with two lists, one for node scope publications and one for cluster scope publications. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: simplify endianness handling in topology subscriber

2018-02-16T20:26:33+00:00

Because of the requirement for total distribution transparency, users send subscriptions and receive topology events in their own host format. It is up to the topology server to determine this format and do the correct conversions to and from its own host format when needed. Until now, this has been handled in a rather non-transparent way inside the topology server and subscriber code, leading to unnecessary complexity when creating subscriptions and issuing events. We now improve this situation by adding two new macros, tipc_sub_read() and tipc_evt_write(). Both those functions calculate the need for conversion internally before performing their respective operations. Hence, all handling of such conversions become transparent to the rest of the code. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: fix bug during lookup of multicast destination nodes

2018-01-15T19:27:13+00:00

In commit 232d07b74a33 ("tipc: improve groupcast scope handling") we inadvertently broke non-group multicast transmission when changing the parameter 'domain' to 'scope' in the function tipc_nametbl_lookup_dst_nodes(). We missed to make the corresponding change in the calling function, with the result that the lookup always fails. A closer anaysis reveals that this parameter is not needed at all. Non-group multicast is hard coded to use CLUSTER_SCOPE, and in the current implementation this will be delivered to all matching destinations except those which are published with NODE_SCOPE on other nodes. Since such publications never will be visible on the sending node anyway, it makes no sense to discriminate by scope at all. We now remove this parameter altogether. Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: improve groupcast scope handling

2018-01-09T17:35:58+00:00

When a member joins a group, it also indicates a binding scope. This makes it possible to create both node local groups, invisible to other nodes, as well as cluster global groups, visible everywhere. In order to avoid that different members end up having permanently differing views of group size and memberhip, we must inhibit locally and globally bound members from joining the same group. We do this by using the binding scope as an additional separator between groups. I.e., a member must ignore all membership events from sockets using a different scope than itself, and all lookups for message destinations must require an exact match between the message's lookup scope and the potential target's binding scope. Apart from making it possible to create local groups using the same identity on different nodes, a side effect of this is that it now also becomes possible to create a cluster global group with the same identity across the same nodes, without interfering with the local groups. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller