From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 8 Jul 2009 19:36:05 +0000 (+0000)
Subject: net: sk_prot_alloc() should not blindly overwrite memory
X-Git-Tag: v2.6.31-rc4~55^2~12
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e912b1142be8f1e2c71c71001dc992c6e5eb2ec1;p=pandora-kernel.git

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>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

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