diff options
Diffstat (limited to 'target/linux/generic/backport-4.19/370-netfilter-nf_flow_table-fix-offloaded-connection-tim.patch')
| -rw-r--r-- | target/linux/generic/backport-4.19/370-netfilter-nf_flow_table-fix-offloaded-connection-tim.patch | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/target/linux/generic/backport-4.19/370-netfilter-nf_flow_table-fix-offloaded-connection-tim.patch b/target/linux/generic/backport-4.19/370-netfilter-nf_flow_table-fix-offloaded-connection-tim.patch new file mode 100644 index 0000000000..e17b4b6204 --- /dev/null +++ b/target/linux/generic/backport-4.19/370-netfilter-nf_flow_table-fix-offloaded-connection-tim.patch @@ -0,0 +1,110 @@ +From: Felix Fietkau <nbd@nbd.name> +Date: Wed, 13 Jun 2018 12:33:39 +0200 +Subject: [PATCH] netfilter: nf_flow_table: fix offloaded connection timeout + corner case + +The full teardown of offloaded flows is deferred to a gc work item, +however processing of packets by netfilter needs to happen immediately +after a teardown is requested, because the conntrack state needs to be +fixed up. + +Since the IPS_OFFLOAD_BIT is still kept until the teardown is complete, +the netfilter conntrack gc can accidentally bump the timeout of a +connection where offload was just stopped, causing a conntrack entry +leak. + +Fix this by moving the conntrack timeout bumping from conntrack core to +the nf_flow_offload and add a check to prevent bogus timeout bumps. + +Signed-off-by: Felix Fietkau <nbd@nbd.name> +--- + +--- a/net/netfilter/nf_conntrack_core.c ++++ b/net/netfilter/nf_conntrack_core.c +@@ -981,18 +981,6 @@ static bool gc_worker_can_early_drop(con + return false; + } + +-#define DAY (86400 * HZ) +- +-/* Set an arbitrary timeout large enough not to ever expire, this save +- * us a check for the IPS_OFFLOAD_BIT from the packet path via +- * nf_ct_is_expired(). +- */ +-static void nf_ct_offload_timeout(struct nf_conn *ct) +-{ +- if (nf_ct_expires(ct) < DAY / 2) +- ct->timeout = nfct_time_stamp + DAY; +-} +- + static void gc_worker(struct work_struct *work) + { + unsigned int min_interval = max(HZ / GC_MAX_BUCKETS_DIV, 1u); +@@ -1029,10 +1017,8 @@ static void gc_worker(struct work_struct + tmp = nf_ct_tuplehash_to_ctrack(h); + + scanned++; +- if (test_bit(IPS_OFFLOAD_BIT, &tmp->status)) { +- nf_ct_offload_timeout(tmp); ++ if (test_bit(IPS_OFFLOAD_BIT, &tmp->status)) + continue; +- } + + if (nf_ct_is_expired(tmp)) { + nf_ct_gc_expired(tmp); +--- a/net/netfilter/nf_flow_table_core.c ++++ b/net/netfilter/nf_flow_table_core.c +@@ -185,8 +185,27 @@ static const struct rhashtable_params nf + .automatic_shrinking = true, + }; + ++#define DAY (86400 * HZ) ++ ++/* Set an arbitrary timeout large enough not to ever expire, this save ++ * us a check for the IPS_OFFLOAD_BIT from the packet path via ++ * nf_ct_is_expired(). ++ */ ++static void nf_ct_offload_timeout(struct flow_offload *flow) ++{ ++ struct flow_offload_entry *entry; ++ struct nf_conn *ct; ++ ++ entry = container_of(flow, struct flow_offload_entry, flow); ++ ct = entry->ct; ++ ++ if (nf_ct_expires(ct) < DAY / 2) ++ ct->timeout = nfct_time_stamp + DAY; ++} ++ + int flow_offload_add(struct nf_flowtable *flow_table, struct flow_offload *flow) + { ++ nf_ct_offload_timeout(flow); + flow->timeout = (u32)jiffies; + + rhashtable_insert_fast(&flow_table->rhashtable, +@@ -307,6 +326,8 @@ static int nf_flow_offload_gc_step(struc + rhashtable_walk_start(&hti); + + while ((tuplehash = rhashtable_walk_next(&hti))) { ++ bool teardown; ++ + if (IS_ERR(tuplehash)) { + err = PTR_ERR(tuplehash); + if (err != -EAGAIN) +@@ -319,9 +340,13 @@ static int nf_flow_offload_gc_step(struc + + flow = container_of(tuplehash, struct flow_offload, tuplehash[0]); + +- if (nf_flow_has_expired(flow) || +- (flow->flags & (FLOW_OFFLOAD_DYING | +- FLOW_OFFLOAD_TEARDOWN))) ++ teardown = flow->flags & (FLOW_OFFLOAD_DYING | ++ FLOW_OFFLOAD_TEARDOWN); ++ ++ if (!teardown) ++ nf_ct_offload_timeout(flow); ++ ++ if (nf_flow_has_expired(flow) || teardown) + flow_offload_del(flow_table, flow); + } + out: |