GHSA-vv6c-69r6-chg9 Go-Landlock in best-effort mode did not restrict TCP bind and connect operations correctly

• Go github.com/landlock-lsm/go-landlock: >= 0.0.0-20240109, < 0.0.0-20241013234402-fb3ad845df46 → fixed in 0.0.0-20241013234402-fb3ad845df46

Impact When using the recommended "best-effort" mode, Go-Landlock did not restrict the TCP bind() and connect() operations any more when they were requested. This affects Go-Landlock users to whom both of the following conditions apply: • They use Landlock rulesets that are supposed to restrict networking (through `landlock.V4`, `landlock.V5`, or self-configured). • These Landlock rulesets are used in best-effort mode. Typically, affected code uses the Go-Landlock API like this (the crucial part being the combination of `V4`/`V5` and `.BestEffort()`): ``` err := landlock.V5.BestEffort().Restrict(...) ``` • This is a bug in the Go-Landlock library and does not affect programs that use Landlock via C or other language bindings. • The bug only affects networking restrictions. File system restrictions continue to work as expected. Patches Patched in: https://github.com/landlock-lsm/go-landlock/commit/fb3ad845df462d013f9c8a965c496617c6a5778b Users should upgrade to: v0.0.0-20241013234402-fb3ad845df46 Go package dependencies can be updated using `go get -u` from the project directory. Projects on Github might get notified by Dependabot, once this advisory is public. Workarounds None. References Currently none. The existing users of Go-Landlock on Github have the following bugs filed: • https://github.com/Foxboron/ssh-the-planet/issues/1 • https://github.com/ngergs/websrv/issues/15 • https://github.com/pufferffish/wireproxy/issues/142