From 0d02d5646eb84403766a11a1d3b19e670a3d45d5 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Sun, 21 May 2017 12:52:58 +0200 Subject: [PATCH] netfilter: conntrack: restart iteration on resize We could some conntracks when a resize occurs in parallel. Avoid this by sampling generation seqcnt and doing a restart if needed. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_core.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 7ecee79c78b8..c3bd9b086dcc 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1623,17 +1623,25 @@ found: static void nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data, u32 portid, int report) { + unsigned int bucket = 0, sequence; struct nf_conn *ct; - unsigned int bucket = 0; might_sleep(); - while ((ct = get_next_corpse(iter, data, &bucket)) != NULL) { - /* Time to push up daises... */ + for (;;) { + sequence = read_seqcount_begin(&nf_conntrack_generation); - nf_ct_delete(ct, portid, report); - nf_ct_put(ct); - cond_resched(); + while ((ct = get_next_corpse(iter, data, &bucket)) != NULL) { + /* Time to push up daises... */ + + nf_ct_delete(ct, portid, report); + nf_ct_put(ct); + cond_resched(); + } + + if (!read_seqcount_retry(&nf_conntrack_generation, sequence)) + break; + bucket = 0; } } -- 2.20.1