René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"`dns.setServers.apply` triggers SIGABRT when passed an address with port 0","articleBody":"### Version\n\nv26.5.1\n\n### Platform\n\n```text\nLinux bombe-mint 6.8.0-136-generic #136-Ubuntu SMP PREEMPT_DYNAMIC Wed Jul  1 21:53:05 UTC 2026 x86_64 x86_64 x86_64 GNU/Linux\n```\n\n### Subsystem\n\n_No response_\n\n### What steps will reproduce the bug?\n\nRun the following code with node `test.js`:\n```js\nconst dns = require('node:dns');\n\nconst callArg = [[ '1.1.1.1:0' ]];\n\ntry {\n    dns.setServers.apply(dns, callArg);\n}\ncatch (e) {\n    console.log(`Exception thrown: ${e} ${e.stack}`);\n}\n```\n\n### How often does it reproduce? Is there a required condition?\n\nIt reproduces reliably every time that the above code is run.\n\n### What is the expected behavior? Why is that the expected behavior?\n\nThe code should work without throwing any error.\n\n### What do you see instead?\n\n```js\n  #  /usr/local/n/versions/node/26.5.1/bin/node[19657]: void node::cares_wrap::(anonymous namespace)::SetServers(const FunctionCallbackInfo\u003cValue> &) at ../src/cares_wrap.cc:2164\n  #  Assertion failed: portValue->Int32Value(env->context()).FromJust()\n\n----- Native stack trace -----\n\n 1: 0x81d228 node::Assert(node::AssertionInfo const&) [/usr/local/n/versions/node/26.5.1/bin/node]\n 2: 0x8b550b  [/usr/local/n/versions/node/26.5.1/bin/node]\n 3: 0x7a67bad8fae9 \n\n----- JavaScript stack trace -----\n\n1: [dns:resolver:setServers] (node:internal/dns/utils:162:38)\n2: setServers (node:internal/dns/utils:154:30)\n3: defaultResolverSetServers (node:dns:309:12)\n4: /home/username/test.js:6:20\n5: node:internal/modules/cjs/loader:1934:14\n6: node:internal/modules/cjs/loader:2074:10\n7: node:internal/modules/cjs/loader:1656:32\n8: node:internal/modules/cjs/loader:1448:12\n9: wrapModuleLoad (node:internal/modules/cjs/loader:261:19)\n10: executeUserEntryPoint (node:internal/modules/run_main:154:5)\n\n\nAborted (core dumped)\n```\n\n### Additional information\n\n_No response_","author":{"url":"https://github.com/davidebombelli","@type":"Person","name":"davidebombelli"},"datePublished":"2026-08-04T09:58:04Z","url":"https://github.com/nodejs/node/issues/65006"}