From: Jason Gunthorpe <jgg@xxxxxxxxxxxx> commit c660133c339f9ab684fdf568c0d51b9ae5e86002 upstream. The intent of this VMA was to be read-only from user space, but the VM_MAYWRITE masking was missed, so mprotect could make it writable. Cc: stable@xxxxxxxxxxxxxxx Fixes: 5c99eaecb1fc ("IB/mlx5: Mmap the HCA's clock info to user-space") Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Reviewed-by: Haggai Eran <haggaie@xxxxxxxxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/main.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -2014,6 +2014,7 @@ static int mlx5_ib_mmap_clock_info_page( if (vma->vm_flags & VM_WRITE) return -EPERM; + vma->vm_flags &= ~VM_MAYWRITE; if (!dev->mdev->clock_info_page) return -EOPNOTSUPP; @@ -2197,6 +2198,7 @@ static int mlx5_ib_mmap(struct ib_uconte if (vma->vm_flags & VM_WRITE) return -EPERM; + vma->vm_flags &= ~VM_MAYWRITE; /* Don't expose to user-space information it shouldn't have */ if (PAGE_SIZE > 4096)