Since KernelSU Manager can now be built for 32-bit, theres this problematic
setup where userspace is 32-bit (armeabi-v7a) and kernel is 64bit (aarch64).
On 64-bit kernels with CONFIG_COMPAT=y, 32-bit userspace passes 32-bit pointers.
These values are interpreted as 64-bit pointers without proper casting and that
results in invalid or near-null memory access.
This patch adds proper compat-mode handling with the ff changes:
- introduce a dedicated struct (`sepol_compat_data`) using u32 fields
- use `compat_ptr()` to safely convert 32-bit user pointers to kernel pointers
- adding a runtime `ksu_is_compat` flag to dynamically select between struct layouts
This prevents a near-null pointer dereference when handling SELinux
policy updates from 32-bit ksud in a 64-bit kernel.
Truth table:
kernel 32 + ksud 32, struct is u32, no compat_ptr
kernel 64 + ksud 32, struct is u32, yes compat_ptr
kernel 64 + ksud 64, struct is u64, no compat_ptr
Preprocessor check
64BIT=y COMPAT=y: define both structs, select dynamically
64BIT=y COMPAT=n: struct u64
64BIT=n: struct u32
Tested-by: ...
Tested-by: ...
Tested-by: ...
Signed-off-by: backslashxx <118538522+backslashxx@users.noreply.github.com>
When the manager UID disappears from packages.list, we correctly
invalidate it — good. But, in the very next breath, we start scanning
/data/app hoping to find it again?
This event is just unnecessary I/O, exactly when we should be doing less.
Apparently this causes hangups and stuckups which is REALLY noticeable
on Ultra-Legacy devices.
Skip the scan — we’ll catch the reinstall next time packages.list updates.
Signed-off-by: backslashxx <118538522+backslashxx@users.noreply.github.com>
This is done like how vfs_read_hook, input_hook and execve_hook is disabled.
While this is not exactly the same thing, this CAN achieve the same results.
The complete disabling of all KernelSU hooks.
While this is likely unneeded, It keeps feature parity to non-kprobe builds.
adapted from upstream:
kernel: Allow to re-enable sucompat - 4593ae81c7
Rejected: https://github.com/tiann/KernelSU/pull/2506
Signed-off-by: backslashxx <118538522+backslashxx@users.noreply.github.com>
