netdev - [PATCH net] netfilter: flowtable: Fix expired flow not being deleted from software

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1588764449-12706-1-git-send-email-paulb@mellanox.com>
Date:   Wed,  6 May 2020 14:27:29 +0300
From:   Paul Blakey <paulb@...lanox.com>
To:     Paul Blakey <paulb@...lanox.com>, Oz Shlomo <ozsh@...lanox.com>,
        Pablo Neira Ayuso <pablo@...filter.org>,
        Roi Dayan <roid@...lanox.com>, netdev@...r.kernel.org,
        Saeed Mahameed <saeedm@...lanox.com>
Cc:     netfilter-devel@...r.kernel.org
Subject: [PATCH net] netfilter: flowtable: Fix expired flow not being deleted from software

Once a flow is considered expired, it is marked as DYING, and
scheduled a delete from hardware. The flow will be deleted from
software, in the next gc_step after hardware deletes the flow
(and flow is marked DEAD). Till that happens, the flow's timeout
might be updated from a previous scheduled stats, or software packets
(refresh). This will cause the gc_step to no longer consider the flow
expired, and it will not be deleted from software.

Fix that by looking at the DYING flag as in deciding
a flow should be deleted from software.

Fixes: c29f74e0df7a ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: Paul Blakey <paulb@...lanox.com>
Reviewed-by: Oz Shlomo <ozsh@...lanox.com>
Reviewed-by: Roi Dayan <roid@...lanox.com>
---
 net/netfilter/nf_flow_table_core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
index c0cb7949..b0e9f7a 100644
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -362,7 +362,8 @@ static void nf_flow_offload_gc_step(struct flow_offload *flow, void *data)
 	struct nf_flowtable *flow_table = data;
 
 	if (nf_flow_has_expired(flow) || nf_ct_is_dying(flow->ct) ||
-	    test_bit(NF_FLOW_TEARDOWN, &flow->flags)) {
+	    test_bit(NF_FLOW_TEARDOWN, &flow->flags) ||
+	    test_bit(NF_FLOW_HW_DYING, &flow->flags)) {
 		if (test_bit(NF_FLOW_HW, &flow->flags)) {
 			if (!test_bit(NF_FLOW_HW_DYING, &flow->flags))
 				nf_flow_offload_del(flow_table, flow);
-- 
1.8.3.1