{"id":"GHSA-gmq2-39ff-f5qg","aliases":[],"status":"published","title":"A failed upgrade may lead to hung goroutines","description":"### Impact\nProcesses using tableflip may encounter hung goroutines in the parent process, after a failed upgrade.\n\nThe Go runtime has annoying behaviour around setting and clearing\nO_NONBLOCK: exec.Cmd.Start() ends up calling os.File.Fd() for any\nfile in exec.Cmd.ExtraFiles. os.File.Fd() disables both the use\nof the runtime poller for the file and clears O_NONBLOCK from\nthe underlying open file descriptor.\n\nThis can lead to goroutines hanging in a parent process, after at least\none failed upgrade. The bug manifests in goroutines which rely on\neither a deadline or interruption via Close() to be unblocked being stuck\nin read or accept like syscalls. As far as I can tell we've not experienced\nthis problem in production, so it's most likely quite rare.\n\n### Patches\nThe problem has been fixed in v1.2.2.\n\n### Workarounds\nNone.\n\n### References\n* https://github.com/cloudflare/tableflip/commit/cae714b289e199db5da5f08af861ea65be6232c0","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2021-05-21T16:25:48Z","modified":"2023-01-09T05:04:34Z","fixes":[{"ecosystem":"Go","package":"github.com/cloudflare/tableflip","fixed_in":["1.2.1","1.2.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"github.com/cloudflare/tableflip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.1"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/cloudflare/tableflip","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.2.2"}]}]}],"references":[{"url":"https://github.com/cloudflare/tableflip/security/advisories/GHSA-gmq2-39ff-f5qg","tags":["web"]},{"url":"https://github.com/cloudflare/tableflip/commit/cae714b289e199db5da5f08af861ea65be6232c0","tags":["web"]},{"url":"https://github.com/advisories/GHSA-gmq2-39ff-f5qg"}],"sources":{"ghsa":[{"id":"GHSA-gmq2-39ff-f5qg","title":"A failed upgrade may lead to hung goroutines","description":"### Impact\nProcesses using tableflip may encounter hung goroutines in the parent process, after a failed upgrade.\n\nThe Go runtime has annoying behaviour around setting and clearing\nO_NONBLOCK: exec.Cmd.Start() ends up calling os.File.Fd() for any\nfile in exec.Cmd.ExtraFiles. os.File.Fd() disables both the use\nof the runtime poller for the file and clears O_NONBLOCK from\nthe underlying open file descriptor.\n\nThis can lead to goroutines hanging in a parent process, after at least\none failed upgrade. The bug manifests in goroutines which rely on\neither a deadline or interruption via Close() to be unblocked being stuck\nin read or accept like syscalls. As far as I can tell we've not experienced\nthis problem in production, so it's most likely quite rare.\n\n### Patches\nThe problem has been fixed in v1.2.2.\n\n### Workarounds\nNone.\n\n### References\n* https://github.com/cloudflare/tableflip/commit/cae714b289e199db5da5f08af861ea65be6232c0","status":"published","published":"2021-05-21T16:25:48Z","modified":"2023-01-09T05:04:34Z","updated_at":"2026-11-02T14:36:10.502376Z"}],"osv":[{"id":"GHSA-gmq2-39ff-f5qg","title":"A failed upgrade may lead to hung goroutines","description":"### Impact\nProcesses using tableflip may encounter hung goroutines in the parent process, after a failed upgrade.\n\nThe Go runtime has annoying behaviour around setting and clearing\nO_NONBLOCK: exec.Cmd.Start() ends up calling os.File.Fd() for any\nfile in exec.Cmd.ExtraFiles. os.File.Fd() disables both the use\nof the runtime poller for the file and clears O_NONBLOCK from\nthe underlying open file descriptor.\n\nThis can lead to goroutines hanging in a parent process, after at least\none failed upgrade. The bug manifests in goroutines which rely on\neither a deadline or interruption via Close() to be unblocked being stuck\nin read or accept like syscalls. As far as I can tell we've not experienced\nthis problem in production, so it's most likely quite rare.\n\n### Patches\nThe problem has been fixed in v1.2.2.\n\n### Workarounds\nNone.\n\n### References\n* https://github.com/cloudflare/tableflip/commit/cae714b289e199db5da5f08af861ea65be6232c0","status":"published","published":"2021-05-21T16:25:48Z","modified":"2021-05-21T14:40:36Z","updated_at":"2026-11-02T15:46:48.191583Z"}]}}