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When munmapping a vma, the mmap_lock can be degraded to a write before calling close() on the file handle. The binder close() function calls binder_alloc_set_vma() to clear the vma address, which now has a lock dep check for writing on the mmap_lock. Change the lockdep check to ensure the reading lock is held while clearing and keep the write check while writing. Link: https://lkml.kernel.org/r/20220627151857.2316964-1-Liam.Howlett@oracle.com Fixes: 472a68df605b ("android: binder: stop saving a pointer to the VMA") Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reported-by: syzbot+da54fa8d793ca89c741f@syzkaller.appspotmail.com Acked-by: Todd Kjos <tkjos@google.com> Cc: "Arve Hjønnevåg" <arve@android.com> Cc: Christian Brauner (Microsoft) <brauner@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hridya Valsaraju <hridya@google.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Martijn Coenen <maco@android.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>