Re: [PATCH net] net: Fix hlist corruptions in inet_evict_bucket()

[David Miller <davem@davemloft.net>]

From: Kirill Tkhai <ktkhai@virtuozzo.com>
Date: Tue, 06 Mar 2018 18:46:39 +0300

> inet_evict_bucket() iterates global list, and
> several tasks may call it in parallel. All of
> them hash the same fq->list_evictor to different
> lists, which leads to list corruption.
> 
> This patch makes fq be hashed to expired list
> only if this has not been made yet by another
> task. Since inet_frag_alloc() allocates fq
> using kmem_cache_zalloc(), we may rely on
> list_evictor is initially unhashed.
> 
> The problem seems to exist before async
> pernet_operations, as there was possible to have
> exit method to be executed in parallel with
> inet_frags::frags_work, so I add two Fixes tags.
> This also may go to stable.
> 
> Fixes: d1fe19444d82 "inet: frag: don't re-use chainlist for evictor"
> Fixes: f84c6821aa54 "net: Convert pernet_subsys, registered from inet_init()"
> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>

Applied and queued up for -stable, thank you.