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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: sk_prot_alloc() should not blindly overwrite
 memory
Date: Sat, 11 Jul 2009 20:27:27 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 09 Jul 2009 07:36:05 +0200

> [PATCH] net: sk_prot_alloc() should not blindly overwrite memory
> 
> Some sockets use SLAB_DESTROY_BY_RCU, and our RCU code correctness
> depends on sk->sk_nulls_node.next being always valid. A NULL
> value is not allowed as it might fault a lockless reader.
> 
> Current sk_prot_alloc() implementation doesnt respect this hypothesis,
> calling kmem_cache_alloc() with __GFP_ZERO. Just call memset() around
> the forbidden field.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

APplied and queued up for -stable.