[PATCH 1/1] XFS: __xfs_get_blocks check pointer to the target device

[Christoph Hellwig]

On Mon, Aug 03, 2009 at 05:03:28PM -0300, Ramon de Carvalho Valle wrote:
> The __xfs_get_blocks function does not check if the pointer to the target
> device is valid before dereferencing it.

It should never be zero.  It's set by xfs_imap_to_bmap to either
mp->m_ddev_targp which is always allocated, or to mp->m_rtdev_targp
which is always allocated if we have a realtime device, and
XFS_IS_REALTIME_INODE should only be true in that case.