Messages in this thread | | | Date | Thu, 18 Nov 2010 12:51:23 -0800 (PST) | Subject | Re: [patch 01/28] fs: d_validate fixes | From | David Miller <> |
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From: Nick Piggin <npiggin@kernel.dk> Date: Wed, 17 Nov 2010 01:09:01 +1100
> d_validate has been broken for a long time. > > kmem_ptr_validate does not guarantee that a pointer can be dereferenced > if it can go away at any time. Even rcu_read_lock doesn't help, because > the pointer might be queued in RCU callbacks but not executed yet. > > So the parent cannot be checked, nor the name hashed. The dentry pointer > can not be touched until it can be verified under lock. Hashing simply > cannot be used. > > Instead, verify the parent/child relationship by traversing parent's > d_child list. It's slow, but only ncpfs and the destaged smbfs care > about it, at this point. > > Signed-off-by: Nick Piggin <npiggin@kernel.dk>
This won't apply because is conflicts with Christoph Hellwig's RCU conversion of d_validate().
Which is a change that went in more than a month ago.
Thus I'd really appreciate if you mentioned what tree your patches are against in your "0/N" posting, always.
Thanks.
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