Check for CAP_SYS_ADMIN since the caller can truncate preallocated blocks from files they do not own nor have write access to. A more fine grained access check was considered: require the caller to specify their own uid/gid and to use inode_permission to check for write, but this would not catch the case of an inode not reachable via path traversal from the callers mount namespace. Add check for read-only filesystem to free eofblocks ioctl. Signed-off-by: Dwight Engen <dwight.engen@xxxxxxxxxx> --- fs/xfs/xfs_ioctl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 6e72eff..b1990ac 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1613,6 +1613,12 @@ xfs_file_ioctl( struct xfs_fs_eofblocks eofb; struct xfs_eofblocks keofb; + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (IS_RDONLY(inode)) + return -XFS_ERROR(EROFS); + if (copy_from_user(&eofb, arg, sizeof(eofb))) return -XFS_ERROR(EFAULT); -- 1.8.1.4 _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
