Messages in this thread | | | Date | Thu, 24 Apr 2008 15:00:00 +0100 | From | Al Viro <> | Subject | Re: [patch 00/13] vfs: add helpers to check r/o bind mounts |
| |
On Thu, Apr 24, 2008 at 02:48:26PM +0100, Al Viro wrote: > On Thu, Apr 24, 2008 at 03:05:21PM +0200, Miklos Szeredi wrote: > > Several calls to nfsd_setattr() for starters. But I didn't do a full > > audit of all vfs_* callers, there might well be others.
BTW, nfsd_setattr() on r/o ->ex_mnt *will* fail. Again, check fh_verify() and see what it does with MAY_SATTR.
And I certainly agree that it ought to be replaced by will/wont pair to close the remount race. One that had been there all along. All fh_verify() callers of that kind need it - we want to pull mnt_{will,wont}_write() pair into callers *and* stretch to protect the entire relevant area.
Which contains vfs_...() in case of nfsd_create, etc. See what I mean? That's exactly the thing I'd been talking about - the area we want to cover is _bigger_ than vfs_...() and contains nfsd-specific logic. IOW, doesn't get folded into any VFS-provided helper.
| |