[NODERAWSOCKETS] Bind-first connect for synchronous getsockname - #27566
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sbc100 merged 1 commit intoAug 27, 2026
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sbc100
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Aug 19, 2026
An unbound TCP client connect created a plain async net.Socket, with saddr/sport only recorded on the async 'connect' event, so getsockname() immediately after a non-blocking connect() returned 0.0.0.0:0. Kernel semantics assign the ephemeral source port synchronously at connect(), so callers (e.g. mio) that read the local address right after a non-blocking connect raced the event loop. connect() now binds an ephemeral port first through the same eager synchronous bindHandle path an explicit bind() takes, then connects through the bound handle, making getsockname() correct up front.
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@sbc100 this one still has approval, is it ok for me to land? |
sbc100
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Aug 27, 2026
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| def test_noderawsockets_connect_getsockname(self): |
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Would it make sense to rename all the tests in this file from test_noderawsockets_xxx to just test_xxx not that they are in their own file? (Or are not all of them raw socket tests)?
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Yeah good point, I can include this in a subsequent cleanup.
sbc100
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Aug 27, 2026
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This fixes an ordering issue in the NODERAWSOCKETS TCP client connect path.
An unbound client connect() created a plain async
net.Socket, withsaddr/sportonly recorded on the async'connect'event, sogetsockname()immediately after a non-blockingconnect()returned0.0.0.0:0. Kernel semantics assign the ephemeral source port synchronously atconnect(), so callers that read the local address right after a non-blocking connect raced the event loop (reliably failing under load).connect()on an unbound socket now binds an ephemeral port first, through the same eager synchronousbindHandlepath an explicitbind()takes, then connects through the bound handle:getsockname()reports the assigned port synchronously afterconnect(), matching kernel behaviornet.BoundSocket, or thetcp_wrapfallback on older node) are synchronous, so this works across node versionsTest coverage:
test_noderawsockets_connect_getsocknameasserts the ephemeral port is non-zero immediately after a non-blockingconnect()returns, before any event loop turn, and that it is unchanged once connected. The test is plain POSIX and passes natively against the host stack.Made with AI assistance under my review