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Title: sqlite: keep sessions alive across SQLite callbacks by TrevorBurnham · Pull Request #65465 · nodejs/node · GitHub

Open Graph Title: sqlite: keep sessions alive across SQLite callbacks by TrevorBurnham · Pull Request #65465 · nodejs/node

X Title: sqlite: keep sessions alive across SQLite callbacks by TrevorBurnham · Pull Request #65465 · nodejs/node

Description: Session calls MakeWeak() and DatabaseSync::sessions_ holds raw Session*, so nothing keeps a session alive once JavaScript drops the reference. SQLite runs PRAGMA table_xinfo from inside its pre-update hook, which reaches JavaScript, so a GC during a callback invoked from there collects the session the hook is still walking: db.createSession(); // return value dropped db.setAuthorizer((a, p1) => { if (p1 === 'table_xinfo') globalThis.gc(); return constants.SQLITE_OK; }); db.exec('INSERT INTO t VALUES (1)'); // segfault in xPreUpdate CallbackDepthGuard already wraps every point where SQLite hands control back to JavaScript (authorizer, trace subscriber, user-defined functions, aggregates, changeset apply), so it now also holds a BaseObjectPtr to each attached session for the callback's duration. BaseObjectPtr clears the weak handle on the first strong reference and restores it on the last, so a session that JavaScript no longer references simply becomes collectable again once the callback returns. Connections with no sessions allocate nothing. Making sessions_ strong instead would create a cycle with Session::database_, which is deliberately strong (a session must keep its database alive), and leak both objects. TraceCallback built its payload before entering the guard. That allocation can trigger a GC, so the guard moves above it. I could not get that window to crash on demand, even with --gc-interval=1, so treat it as defensive rather than a demonstrated fix. Fixes: #65460

Open Graph Description: Session calls MakeWeak() and DatabaseSync::sessions_ holds raw Session*, so nothing keeps a session alive once JavaScript drops the reference. SQLite runs PRAGMA table_xinfo from inside its pre-upd...

X Description: Session calls MakeWeak() and DatabaseSync::sessions_ holds raw Session*, so nothing keeps a session alive once JavaScript drops the reference. SQLite runs PRAGMA table_xinfo from inside its pre-upd...

Opengraph URL: https://github.com/nodejs/node/pull/65465

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