On Mon, 19 Sept 2022 at 06:25, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > > Hi Tadeusz, > > Looking at places like these: > https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/infiniband/hw/qib/qib_file_ops.c#L736 > https://elixir.bootlin.com/linux/v6.0-rc5/source/drivers/infiniband/hw/mlx5/main.c#L2088 > I think we also need to remove VM_MAYWRITE, otherwise it's still > possible to turn it into a writable mapping with mprotect. > > It's also probably better to return an error if VM_WRITE (or VM_EXEC?) is set > rather than silently fix it up. The credit for the VM_MAYWRITE suggestion goes to the PaX Team. Suggested-by: PaX Team <pageexec@xxxxxxxxxxx>