kernel & KernelSU: Added switch for enabling/disabling umount for zygote spawned isolated service process
- Some modules that overlay sysyem files like framework or other overlay apk may crash when all iso services are umounted by susfs, so a switch is made here for users to switch on/off this funtion at anytime when they need it or want to test it
- By default it is disabled in kernel, run "ksu_susfs umount_for_zygote_iso_service <0|1>" to switch on/off the function in userspace
- Also user can create new file to "/data/adb/susfs_umount_for_zygote_iso_service" to enable it in kernel on each boot
- Alternatively, disable this function and use other modules to handle the umount for iso services until a better solution is found
Co-authored-by: simonpunk <simonpunk2016@gmail.com>
* Since it's interceptable from LSM Hook,
then we just need to remove ksu_handle_devpts and
make a decoy for it.
Signed-off-by: rsuntk <rsuntk@yukiprjkt.my.id>
Use strscpy()/strlcpy() to populate the version buffer in CMD_GET_FULL_VERSION
instead of relying on uninitialized memory. This ensures the returned string
is null-terminated and avoids exposing garbage data to user space.
Signed-off-by: schqiushui <orochi9999@gmail.com>
Fixed function definition and restored missing ksu_try_umount calls that were unintentionally removed in previous commits. This includes unmounts for:
- /debug_ramdisk
- /sbin
- /system/etc/hosts
- /apex/com.android.art/bin/dex2oat64
- /apex/com.android.art/bin/dex2oat32
Fixes: b443b11df9 ("kernel: Refactoring the mount point unloading logic")
Fixes: da7632470d ("kernel: 使用 try_umount 替换 ksu_try_umount 以统一卸载逻辑")
Signed-off-by: schqiushui <orochi9999@gmail.com>
* Some people reports about undefined reference to `sys_umount`
* Since ksys_umount exist on Linux 4.17-rc1, then we gonna use that one.
Rev 2: Use correct int instead of long for ksys_umount
Signed-off-by: rsuntk <90097027+rsuntk@users.noreply.github.com>
I am repasting here what I posted on the source code originally:
/*
* turns out path_umount backport is completely unneeded
* we copy the trick used on strncpy_from_unsafe_user / strncpy_from_user_nofault
* https://elixir.bootlin.com/linux/v4.4.302/source/mm/maccess.c#L184
* basically
*
* mm_segment_t old_fs = get_fs(); // remember original fs segment
* set_fs(USER_DS); // or KERNEL_DS *
* do_whatever_in_userspace();
* set_fs(old_fs); // restore fs segment
*
* * kernel -> user, KERNEL_DS, user -> kernel, USER_DS
*
* so yes, we can try to straight up call a syscall from kernel space
*
* NOTE: on newer kernels you can use force_uaccess_begin + force_uaccess_end
* ref: https://elixir.bootlin.com/linux/v5.10.237/source/mm/maccess.c#L250
*
*/
path_umount backport now optional — neat trick, werks, what can I say.
Backports? Nah, we’re good.
Signed-off-by: backslashxx <118538522+backslashxx@users.noreply.github.com>
