| Message ID | 1291566397-24318-1-git-send-email-xiaosuo@gmail.com |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
Am 05.12.2010 17:26, schrieb Changli Gao: > Since nf_ct_expect_dst_hash() may be called without nf_conntrack_lock > locked, nf_ct_expect_hash_rnd should be initialized in the atomic way. > > Signed-off-by: Changli Gao <xiaosuo@gmail.com> > --- > net/netfilter/nf_conntrack_expect.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c > index 46e8966..e2bb3ef 100644 > --- a/net/netfilter/nf_conntrack_expect.c > +++ b/net/netfilter/nf_conntrack_expect.c > @@ -34,7 +34,6 @@ EXPORT_SYMBOL_GPL(nf_ct_expect_hsize); > > static unsigned int nf_ct_expect_hash_rnd __read_mostly; > unsigned int nf_ct_expect_max __read_mostly; > -static int nf_ct_expect_hash_rnd_initted __read_mostly; > > static struct kmem_cache *nf_ct_expect_cachep __read_mostly; > > @@ -77,10 +76,13 @@ static unsigned int nf_ct_expect_dst_hash(const struct nf_conntrack_tuple *tuple > { > unsigned int hash; > > - if (unlikely(!nf_ct_expect_hash_rnd_initted)) { > - get_random_bytes(&nf_ct_expect_hash_rnd, > - sizeof(nf_ct_expect_hash_rnd)); > - nf_ct_expect_hash_rnd_initted = 1; > + if (unlikely(!nf_ct_expect_hash_rnd)) { > + unsigned int rand; > + > + do { > + get_random_bytes(&rand, sizeof(rand)); > + } while (!rand); > + cmpxchg(&nf_ct_expect_hash_rnd, 0, rand); > } I'd rather just re-use the conntrack hash random value. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c index 46e8966..e2bb3ef 100644 --- a/net/netfilter/nf_conntrack_expect.c +++ b/net/netfilter/nf_conntrack_expect.c @@ -34,7 +34,6 @@ EXPORT_SYMBOL_GPL(nf_ct_expect_hsize); static unsigned int nf_ct_expect_hash_rnd __read_mostly; unsigned int nf_ct_expect_max __read_mostly; -static int nf_ct_expect_hash_rnd_initted __read_mostly; static struct kmem_cache *nf_ct_expect_cachep __read_mostly; @@ -77,10 +76,13 @@ static unsigned int nf_ct_expect_dst_hash(const struct nf_conntrack_tuple *tuple { unsigned int hash; - if (unlikely(!nf_ct_expect_hash_rnd_initted)) { - get_random_bytes(&nf_ct_expect_hash_rnd, - sizeof(nf_ct_expect_hash_rnd)); - nf_ct_expect_hash_rnd_initted = 1; + if (unlikely(!nf_ct_expect_hash_rnd)) { + unsigned int rand; + + do { + get_random_bytes(&rand, sizeof(rand)); + } while (!rand); + cmpxchg(&nf_ct_expect_hash_rnd, 0, rand); } hash = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all),
Since nf_ct_expect_dst_hash() may be called without nf_conntrack_lock locked, nf_ct_expect_hash_rnd should be initialized in the atomic way. Signed-off-by: Changli Gao <xiaosuo@gmail.com> --- net/netfilter/nf_conntrack_expect.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html