From: Florian Westphal <fw@xxxxxxxxx>
If userspace program exits while the queue its subscribed to has packets
those need to be discarded.
commit dc21c6cc3d69 ("netfilter: nfnetlink_queue: acquire rcu_read_lock()
in instance_destroy_rcu()") fixed a (harmless) rcu splat that could be
triggered in this case.
Add a test case to cover this.
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
.../selftests/net/netfilter/nft_queue.sh | 37 +++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/tools/testing/selftests/net/netfilter/nft_queue.sh b/tools/testing/selftests/net/netfilter/nft_queue.sh
index 288b3cc55ed7..7e210d75e738 100755
--- a/tools/testing/selftests/net/netfilter/nft_queue.sh
+++ b/tools/testing/selftests/net/netfilter/nft_queue.sh
@@ -449,6 +449,42 @@ EOF
wait "$rpid" && echo "PASS: sctp and nfqueue in output chain with GSO"
}
+test_queue_removal()
+{
+ read tainted_then < /proc/sys/kernel/tainted
+
+ ip netns exec "$ns1" nft -f - <<EOF
+flush ruleset
+table ip filter {
+ chain output {
+ type filter hook output priority 0; policy accept;
+ ip protocol icmp queue num 0
+ }
+}
+EOF
+ ip netns exec "$ns1" ./nf_queue -q 0 -d 30000 -t "$timeout" &
+ local nfqpid=$!
+
+ busywait "$BUSYWAIT_TIMEOUT" nf_queue_wait "$ns1" 0
+
+ ip netns exec "$ns1" ping -w 2 -f -c 10 127.0.0.1 -q >/dev/null
+ kill $nfqpid
+
+ ip netns exec "$ns1" nft flush ruleset
+
+ if [ "$tainted_then" -ne 0 ];then
+ return
+ fi
+
+ read tainted_now < /proc/sys/kernel/tainted
+ if [ "$tainted_now" -eq 0 ];then
+ echo "PASS: queue program exiting while packets queued"
+ else
+ echo "TAINT: queue program exiting while packets queued"
+ ret=1
+ fi
+}
+
ip netns exec "$nsrouter" sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
ip netns exec "$nsrouter" sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
ip netns exec "$nsrouter" sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null
@@ -489,5 +525,6 @@ test_tcp_localhost_requeue
test_icmp_vrf
test_sctp_forward
test_sctp_output
+test_queue_removal
exit $ret
--
2.30.2
