[PROTON-2027] Proactor connection wake after memory freed when using pn_proactor_disconnect().

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: proton-c-0.27.0
• Fix Version/s: proton-c-0.27.1
• Component/s: proton-c
• Assignee: Clifford Jansen
• Reporter: Clifford Jansen
• Created: 04/Apr/19 20:21
• Updated: 23/Apr/19 11:05
• Resolved: 11/Apr/19 06:21

Description

The normal cleanup procedure for epoll and win_iocp proactors waits for all async activity to complete before freeing memory.

pn_proactor_disconnect can't actually force a close so it launches a separate async activity piggy-backed on the internal wake mechanism of any connections to be closed.

If the disconnect is happening at the same time as a separate thread doing a normal close, a new wake can result after concluding there are none left.

The solution is to mark the connection as "already awake" before entering the cleanup code so new wakes are no-ops.  The libuv proactor doesn't need this as the disconnect function is managed within libuv and never competes with the normal close operation.