Re: [PATCH] netfilter:get_next_corpse():No need to double check the *bucket

From: Florian Westphal
Date: Tue Oct 01 2019 - 05:37:07 EST


wh_bin@xxxxxxx <wh_bin@xxxxxxx> wrote:
> From: Hongbin Wang <wh_bin@xxxxxxx>
>
> The *bucket is in for loops,it has been checked.
>
> Signed-off-by: Hongbin Wang <wh_bin@xxxxxxx>
> ---
> net/netfilter/nf_conntrack_core.c | 14 ++++++--------
> 1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
> index 0c63120b2db2..8d48babe6561 100644
> --- a/net/netfilter/nf_conntrack_core.c
> +++ b/net/netfilter/nf_conntrack_core.c
> @@ -2000,14 +2000,12 @@ get_next_corpse(int (*iter)(struct nf_conn *i, void *data),
> lockp = &nf_conntrack_locks[*bucket % CONNTRACK_LOCKS];
> local_bh_disable();
> nf_conntrack_lock(lockp);
> - if (*bucket < nf_conntrack_htable_size) {
> - hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[*bucket], hnnode) {
> - if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
> - continue;
> - ct = nf_ct_tuplehash_to_ctrack(h);
> - if (iter(ct, data))
> - goto found;
> - }
> + hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[*bucket], hnnode) {

I don't think this is correct.
unless we hold nf_conntrack_lock() nf_conntrack_hash[] could be
reallocated, no?