From: Johannes B. <joh...@si...> - 2016-08-02 05:50:29
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On Tue, 2016-08-02 at 01:30 +0100, Al Viro wrote: > On Mon, Aug 01, 2016 at 09:57:17PM +0200, Johannes Berg wrote: > > The introduction of v9fs_parent_fid() broke v9fs_vfs_rename() > > since that doesn't just do v9fs_fid_lookup() but rather uses > > v9fs_fid_clone() on the ->d_parent. > > > > I suppose it'd be possible to introduce v9fs_clone_parent_fid() > > but I decided that just reverting the broken change was better > > for now. > > Sorry for the braino; FWIW, I'd rather add > > static inline struct p9_fid *fid_clone(struct p9_fid *fid) > { > if (IS_ERR(fid)) > return fid; > return p9_client_walk(fid, 0, NULL, 1); > } > > and turn those into fid_clone(v9fs_parent_fid(old_dentry)), etc. That would have required much more looking into what happens than I was about to do :) > Has an extra benefit of simplifying several other places. I'll fix > and post (with credits to you for spotting the bug in question, of > course). No objection, I just did the minimum necessary to make my setup not crash on use-after-free all the time (thanks to slab debug) :) Thanks, johannes |