KarpelesLab / slirp / 23943364098

71%

Build Type

push

github

Committed by MagicalTux

Commit Message

Fix 8 bugs: deadlocks, protocol errors, missing EOF, stray packets

1. tcpConn sends packets outside mutex — fixes deadlock in Pipe
   scenarios where synchronous delivery re-enters handleOutbound.
   All packet sends now use queue+drain pattern (same as VirtualConn).
   Applied to handleOutbound, readFromRemote, flushSendQ, maintenanceLoop
   for both IPv4 and IPv6.

2. FIN now increments sSeq (consumes sequence number) — the client's
   ACK for our FIN is properly detected, closing the connection instead
   of waiting for the 2-minute idle timeout.

3. vclient Read() returns io.EOF after remote FIN when data drained —
   previously blocked forever because it only checked 'closed' flag.

4. Stack.Close() uses sync.Once — no longer panics on double call.

5. vclient FinWait1+FIN without ACK → Closing state (was CloseWait).
   Added tcpClosing state per RFC 793 simultaneous close.

6. Non-SYN packets to non-existent connections get RST instead of
   silently creating useless map entries.

7. net.Dial moved outside mutex — no longer blocks Stack maintenance.
   On dial failure, sends RST+ACK to client.

8. VirtualConn/VirtualConn6 send duplicate ACKs for out-of-order data,
   consistent with tcpConn behavior.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Coverage Stats

131 of 193 new or added lines in 7 files covered. (67.88%)

6 existing lines in 2 files now uncovered.

2737 of 3426 relevant lines covered (79.89%)

11.73 hits per line