fixeria has submitted this change. ( https://gerrit.osmocom.org/c/erlang/osmo-s1gw/+/42297?usp=email )

Change subject: enb_registry: fix duplicate registration check in enb_register/0 ......................................................................

enb_registry: fix duplicate registration check in enb_register/0

next_handle was bound in the function head and reused in the case pattern {ok, Handle}, turning what looks like a binding into an equality test against next_handle. The duplicate check therefore only fired if the previously assigned handle happened to equal the current next_handle counter, which is essentially never true.

Fix by removing next_handle from the function head pattern and reading it with S#state.next_handle inside the error branch, so that Handle in {ok, Handle} is always a fresh binding that matches any existing handle.

Change-Id: Ia64f3e2e79bea055e5c37df9bce91a4bcbf7184c --- M src/enb_registry.erl 1 file changed, 2 insertions(+), 2 deletions(-)

Approvals: osmith: Looks good to me, but someone else must approve Jenkins Builder: Verified pespin: Looks good to me, but someone else must approve fixeria: Looks good to me, approved

diff --git a/src/enb_registry.erl b/src/enb_registry.erl index d2487a0..29a2575 100644 --- a/src/enb_registry.erl +++ b/src/enb_registry.erl @@ -155,13 +155,13 @@ handle_call(enb_register, {Pid, _Tag}, #state{enbs = ENBs, - pids = PIDs, - next_handle = Handle} = S) -> + pids = PIDs} = S) -> case maps:find(Pid, PIDs) of {ok, Handle} -> ?LOG_ERROR("eNB (handle=~p, pid=~p) is *already* registered", [Handle, Pid]), {reply, {error, already_registered}, S}; error -> + Handle = S#state.next_handle, %% keep an eye on the process being registered MonRef = erlang:monitor(process, Pid), %% create and store an initial eNB state