This reverts commit 5195c14c8b27cc0b18220ddbf0e5ad3328a04187. If the conntrack clashes with an existing one, it is left out of the unconfirmed, thus, crashing when dropping the packet and releasing the conntrack. Reported-by: Daniel Borkmann <dborkman@xxxxxxxxxx> Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=88841 Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- I prefer to revert the original fix and replace it by the follow up to pass one single patch to -stable. 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 2c69975..5016a69 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -611,16 +611,12 @@ __nf_conntrack_confirm(struct sk_buff *skb) */ NF_CT_ASSERT(!nf_ct_is_confirmed(ct)); pr_debug("Confirming conntrack %p\n", ct); - - /* We have to check the DYING flag after unlink to prevent - * a race against nf_ct_get_next_corpse() possibly called from - * user context, else we insert an already 'dead' hash, blocking - * further use of that particular connection -JM. - */ - nf_ct_del_from_dying_or_unconfirmed_list(ct); + /* We have to check the DYING flag inside the lock to prevent + a race against nf_ct_get_next_corpse() possibly called from + user context, else we insert an already 'dead' hash, blocking + further use of that particular connection -JM */ if (unlikely(nf_ct_is_dying(ct))) { - nf_ct_add_to_dying_list(ct); nf_conntrack_double_unlock(hash, reply_hash); local_bh_enable(); return NF_ACCEPT; @@ -640,6 +636,8 @@ __nf_conntrack_confirm(struct sk_buff *skb) zone == nf_ct_zone(nf_ct_tuplehash_to_ctrack(h))) goto out; + nf_ct_del_from_dying_or_unconfirmed_list(ct); + /* Timer relative to confirmation time, not original setting time, otherwise we'd get timer wrap in weird delay cases. */ -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
