Binder regression caused by commit a43cfc87caaf

[Ondrej Mosnacek]

Hello,

FYI, since commit a43cfc87caaf ("android: binder: stop saving a
pointer to the VMA") (found by git bisect) the binder test in
selinux-testsuite [1] started to trigger a lockdep assert BUG() in
find_vma() - see the end of [2] for an example.

A minimal reproducer is:
```
git clone https://github.com/SELinuxProject/selinux-testsuite.git
cd selinux-testsuite/tests/binder
make
setenforce 0  # if SELinux is enabled
./init_binder.sh || true
./manager -n -v & sleep 2
./service_provider -n -v
```
Requires the equivalent of libselinux-devel, make, gcc, and git-core
Fedora packages.
The last command will trigger the BUG; on good kernels it will
successfully enter the ioctl loop.

[1] https://github.com/SELinuxProject/selinux-testsuite/
[2] https://s3.us-east-1.amazonaws.com/arr-cki-prod-datawarehouse-public/datawarehouse-public/2022/08/07/redhat:606549366/build_x86_64_redhat:606549366_x86_64/tests/5/results_0001/console.log/console.log

-- 
Ondrej Mosnacek
Senior Software Engineer, Linux Security - SELinux kernel
Red Hat, Inc.