Stop the LSPosed hooks' debug flag from depending on inotify - #317
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Found on a live Pixel 8 Pro: system_server was writing VpnHide-NC/NI lines to logcat — the ones that name the exact UIDs we hook — at ~3/s, five days after Debug logging had been turned off. The canonical config on disk said debug:false and had said so since the day after that boot. HookLog.enabled was assigned in exactly one place, HookLog.reload(), reachable only from install() at boot and from the FileObserver callback. That observer had stopped delivering: an atomic rename over the config produced no callback at all, confirmed on the device. So the flag was frozen at whatever the config said at boot, and no amount of toggling in the app could move it — only a reboot. The irony is that SystemServerConfigCache sits right beside it re-reading the same file every second by fingerprint, and was current the whole time. The hooks' targeting was right; only the logging flag was stale. So give the flag to the component that already polls: the cache sets HookLog.enabled whenever it installs a fresh config. The watcher stays, as latency rather than correctness — it makes a flip land immediately instead of within a second — and the comments now say so, because the next person to add state here will be tempted to hang it off the same callback. Not a leak: nothing an app can read. It is a toggle that silently did nothing, plus a stream of Binder-hot-path log calls the user asked us to stop making.
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Found while investigating an unrelated report on a live Pixel 8 Pro: system_server was writing
VpnHide-NC/VpnHide-NIlines — the ones that name the exact UIDs we hook — at roughly 3/s, five days after Debug logging had been switched off. The canonical config on disk saiddebug: falseand had said so since the day after that boot.HookLog.enabledwas assigned in exactly one place,HookLog.reload(), reachable only frominstall()at boot and from theFileObservercallback. That observer had stopped delivering — an atomic rename over the config produced no callback at all, confirmed on the device — so the flag was frozen at its boot value and no amount of toggling in the app could move it. Only a reboot could.SystemServerConfigCachesits right beside it re-reading the same file every second by fingerprint, and was current the whole time: the hooks' targeting was correct, only the logging flag was stale. So the flag now belongs to the component that already polls.SystemServerConfigCachesetsHookLog.enabledwhenever it installs a freshly-read configHookLog.install()primes through that same path;reload()is goneNot a leak — nothing an app can read. It is a toggle that silently did nothing, plus a stream of log calls on a Binder hot path that the user had asked us to stop making.
Testing: the stale-flag state was reproduced and confirmed on hardware (atomic rename over the config produced no observer callback while the cache stayed current). End-to-end verification of the fix needs the module reloaded into system_server, i.e. a reboot on a test device.