In the constructor of mmap_data, there are two possible values when fails: nullptr if fstat() fails, and MAP_FAILED if mmap() fails, but mmap_data treated MAP_FAILED as valid address and crashes.
faccessat() should return 0 when success, but it returns random number with errno == 0 in x86 platform.
It’s a side effect of commit bf80b08b5f when magisk binaries ‘corretly’ linked with library of API16 .. lol
Co-authored-by: John Wu <topjohnwu@gmail.com>
It is possible that a module is breaking the device so bad that zygote
cannot even be started. In this case, system_server cannot start and
detect the safe mode key combo, set the persist property, and reboot.
Also on old Android versions, the system directly goes to safe mode
after detecting a key combo without rebooting, defeating the purpose of
Magisk's safe mode protection if we only check for the persist property.
Directly adding key combo check natively in magiskd allows us to enter
Magisk safe mode before the system is even aware of it.
Before switching to the new MagiskHide implementation (APK inotify),
logcat parsing provides us lots of information to target a process.
We were targeting components so that apps with multi-processes
can still be hidden properly.
After switching to the new implementation, our granularity is limited
to the UID of the process. This is especially dangerous since Android
allow apps signed with the same signature to share UIDs, and many system
apps utilize this for elevated permissions for some services.
This commit introduces process name matching. We could not blanketly
target an UID, so the workaround is to verify its process name before
unmounting.
The tricky thing is that any app developer is allowed to name the
process of its component to whatever they want; there is no 'one
rule to catch them all' to target a specific package. As a result,
Magisk Manager is updated to scan through all components of all apps,
and show different processes of the same app, each as a separate
hide target in the list.
The hide target database also has to be updated accordingly.
Each hide target is now a <package name, process name> pair. The
magiskhide CLI and Magisk Manager is updated to support this new
target format.
