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[IPV4] ROUTE: fix rcu_dereference() uses in /proc/net/rt_cache

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In rt_cache_get_next(), no need to guard seq->private by a
rcu_dereference() since seq is private to the thread running this
function. Reading seq.private once (as guaranted bu rcu_dereference())
or several time if compiler really is dumb enough wont change the
result.

But we miss real spots where rcu_dereference() are needed, both in
rt_cache_get_first() and rt_cache_get_next()

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2008-01-10 03:55:57 -08:00 committed by David S. Miller
parent 9cd4002942
commit 0bcceadceb
1 changed files with 3 additions and 3 deletions
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6
net/ipv4/route.c
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@ -283,12 +283,12 @@ static struct rtable *rt_cache_get_first(struct seq_file *seq)
break; break;
rcu_read_unlock_bh(); rcu_read_unlock_bh();
} }
return r; return rcu_dereference(r);
} }
static struct rtable *rt_cache_get_next(struct seq_file *seq, struct rtable *r) static struct rtable *rt_cache_get_next(struct seq_file *seq, struct rtable *r)
{ {
struct rt_cache_iter_state *st = rcu_dereference(seq->private); struct rt_cache_iter_state *st = seq->private;
r = r->u.dst.rt_next; r = r->u.dst.rt_next;
while (!r) { while (!r) {
@ -298,7 +298,7 @@ static struct rtable *rt_cache_get_next(struct seq_file *seq, struct rtable *r)
rcu_read_lock_bh(); rcu_read_lock_bh();
r = rt_hash_table[st->bucket].chain; r = rt_hash_table[st->bucket].chain;
} }
return r; return rcu_dereference(r);
} }
static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos)