If we allocate less than sizeof(struct attrlist) then we end up corrupting memory or doing a ZERO_PTR_SIZE dereference. This can only be triggered with CAP_SYS_ADMIN. Reported-by: Nico Golde <nico@xxxxxxxxx> Reported-by: Fabian Yamaguchi <fabs@xxxxxxxxx> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 4d61340..33ad9a7 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -442,7 +442,8 @@ xfs_attrlist_by_handle( return -XFS_ERROR(EPERM); if (copy_from_user(&al_hreq, arg, sizeof(xfs_fsop_attrlist_handlereq_t))) return -XFS_ERROR(EFAULT); - if (al_hreq.buflen > XATTR_LIST_MAX) + if (al_hreq.buflen < sizeof(struct attrlist) || + al_hreq.buflen > XATTR_LIST_MAX) return -XFS_ERROR(EINVAL); /* diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c index e8fb123..a7992f8 100644 --- a/fs/xfs/xfs_ioctl32.c +++ b/fs/xfs/xfs_ioctl32.c @@ -356,7 +356,8 @@ xfs_compat_attrlist_by_handle( if (copy_from_user(&al_hreq, arg, sizeof(compat_xfs_fsop_attrlist_handlereq_t))) return -XFS_ERROR(EFAULT); - if (al_hreq.buflen > XATTR_LIST_MAX) + if (al_hreq.buflen < sizeof(struct attrlist) || + al_hreq.buflen > XATTR_LIST_MAX) return -XFS_ERROR(EINVAL); /* _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
