From e951bcbff729b0eae1e1743c2bbb27064bbaf165 Mon Sep 17 00:00:00 2001 From: Csaba Kiraly Date: Tue, 24 Mar 2026 14:57:11 +0100 Subject: [PATCH] cmd/devp2p: fix discv5 PingMultiIP test session key mismatch (#34031) conn.read() used the actual UDP packet source address for codec.Decode(), but conn.write() always used tc.remoteAddr. When the remote node is reachable via multiple Docker networks, the packet source IP differs from tc.remoteAddr, causing a session key lookup failure in the codec. Use tc.remoteAddr.String() consistently in conn.read() so the session cache key matches what was used during Encode. --- cmd/devp2p/internal/v5test/framework.go | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/cmd/devp2p/internal/v5test/framework.go b/cmd/devp2p/internal/v5test/framework.go index 92a5048150..acab1eef79 100644 --- a/cmd/devp2p/internal/v5test/framework.go +++ b/cmd/devp2p/internal/v5test/framework.go @@ -218,11 +218,15 @@ func (tc *conn) read(c net.PacketConn) v5wire.Packet { if err := c.SetReadDeadline(time.Now().Add(waitTime)); err != nil { return &readError{err} } - n, fromAddr, err := c.ReadFrom(buf) + n, _, err := c.ReadFrom(buf) if err != nil { return &readError{err} } - _, _, p, err := tc.codec.Decode(buf[:n], fromAddr.String()) + // Always use tc.remoteAddr for session lookup. The actual source address of + // the packet may differ from tc.remoteAddr when the remote node is reachable + // via multiple networks (e.g. Docker bridge vs. overlay), but the codec's + // session cache is keyed by the address used during Encode. + _, _, p, err := tc.codec.Decode(buf[:n], tc.remoteAddr.String()) if err != nil { return &readError{err} }