Add missing close call when SO_REUSEPORT is used for UDP socket and there's a conflict

[Jarred-Sumner]

What does this PR do?

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[robobun]

^{Updated 5:31 AM PT - Sep 19th, 2025}

❌ @Jarred-Sumner, your commit 2bb9f3a has 2 failures in Build #26331 (All Failures):

• test/js/sql/sql-mysql.auth.test.ts - timeout on 🍎 14 aarch64
• test/js/node/test/parallel/test-fs-promises-watch.js - pid 6457 error: addresssanitizer on 🐧 12 x64-asan

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[coderabbitai]

Walkthrough

Updates in packages/bun-usockets/src/bsd.c adjust error handling in bsd_create_udp_socket by adding socket closure and addrinfo cleanup on specific failure paths and removing a non-functional comment. No public API changes.

Changes

Cohort / File(s)	Summary of Changes
UDP socket error handling cleanup packages/bun-usockets/src/bsd.c	Removed a non-functional comment. Added resource cleanup on errors: close listenFd when bsd_set_reuse fails; freeaddrinfo(result) and close listenFd when IPV6_V6ONLY handling fails. No public API changes.

Pre-merge checks and finishing touches

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description Check	⚠️ Warning	The PR description contains only the template headings with no substantive content, so it does not satisfy the repository template sections "What does this PR do?" and "How did you verify your code works?" and therefore is incomplete.	Populate "What does this PR do?" with a concise summary of the fix (e.g., add bsd_close_socket() on error paths for UDP SO_REUSEPORT conflicts and the affected file path), and populate "How did you verify your code works?" with concrete verification steps including tests run, commands to reproduce, test outputs or CI links, and platforms tested; update the PR body with these details before requesting review.
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The title succinctly and accurately describes the primary change: adding a missing close call when SO_REUSEPORT causes a UDP socket conflict, which matches the raw_summary showing added bsd_close_socket() on error paths in the UDP socket creation code. It is concise, on-topic, and readable for a reviewer scanning the PR history.

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• Post copyable unit tests in a comment
• Commit unit tests in branch jarred/socket-close-udp

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[coderabbitai]

Actionable comments posted: 0

🧹 Nitpick comments (2)

packages/bun-usockets/src/bsd.c (2)

1220-1224: Propagate and preserve err before cleanup on bsd_set_reuse failure.

Today the function drops the specific failure code. Capture errno/WSAGetLastError before free/close and assign to err so callers can diagnose why SO_REUSEPORT/addr reuse failed.

-    if (bsd_set_reuse(listenFd, options) != 0) {
-        freeaddrinfo(result);
-        bsd_close_socket(listenFd);
-        return LIBUS_SOCKET_ERROR;
-    }
+    if (bsd_set_reuse(listenFd, options) != 0) {
+#ifdef _WIN32
+        int saved_err = WSAGetLastError();
+#else
+        int saved_err = errno;
+#endif
+        freeaddrinfo(result);
+        bsd_close_socket(listenFd);
+        if (err) { *err = saved_err; }
+        return LIBUS_SOCKET_ERROR;
+    }

---

1227-1233: Also set err on IPV6_V6ONLY failure (and preserve before cleanup).

Same rationale: return path should propagate the setsockopt failure code.

-        if (setsockopt(listenFd, IPPROTO_IPV6, IPV6_V6ONLY, &enabled, sizeof(enabled)) != 0) {
-            freeaddrinfo(result);
-            bsd_close_socket(listenFd);
-            return LIBUS_SOCKET_ERROR;
-        }
+        if (setsockopt(listenFd, IPPROTO_IPV6, IPV6_V6ONLY, &enabled, sizeof(enabled)) != 0) {
+#ifdef _WIN32
+            int saved_err = WSAGetLastError();
+#else
+            int saved_err = errno;
+#endif
+            freeaddrinfo(result);
+            bsd_close_socket(listenFd);
+            if (err) { *err = saved_err; }
+            return LIBUS_SOCKET_ERROR;
+        }

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• packages/bun-usockets/src/bsd.c (1 hunks)

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🔇 Additional comments (1)

packages/bun-usockets/src/bsd.c (1)

1220-1231: Good fix — UDP FD + addrinfo cleanup verified.
All error paths in bsd_create_udp_socket now call freeaddrinfo(result) and bsd_close_socket(listenFd) before returning; no FD leaks found.