[PATCH net] net: mscc: ocelot: fix all IP traffic getting trapped to CPU with PTP over IP

[PATCH net] net: mscc: ocelot: fix all IP traffic getting trapped to CPU with PTP over IP

[Vladimir Oltean]

The filters for the PTP trap keys are incorrectly configured, in the
sense that is2_entry_set() only looks at trap->key.ipv4.dport or
trap->key.ipv6.dport if trap->key.ipv4.proto or trap->key.ipv6.proto is
set to IPPROTO_TCP or IPPROTO_UDP.

But we don't do that, so is2_entry_set() goes through the "else" branch
of the IP protocol check, and ends up installing a rule for "Any IP
protocol match" (because msk is also 0). The UDP port is ignored.

This means that when we run "ptp4l -i swp0 -4", all IP traffic is
trapped to the CPU, which hinders bridging.

Fix this by specifying the IP protocol in the VCAP IS2 filters for PTP
over UDP.

Fixes: 96ca08c05838 ("net: mscc: ocelot: set up traps for PTP packets")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/ethernet/mscc/ocelot.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 455293aa6343..354e4474bcc3 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -1432,6 +1432,8 @@ static void
 ocelot_populate_ipv4_ptp_event_trap_key(struct ocelot_vcap_filter *trap)
 {
 	trap->key_type = OCELOT_VCAP_KEY_IPV4;
+	trap->key.ipv4.proto.value[0] = IPPROTO_UDP;
+	trap->key.ipv4.proto.mask[0] = 0xff;
 	trap->key.ipv4.dport.value = PTP_EV_PORT;
 	trap->key.ipv4.dport.mask = 0xffff;
 }
@@ -1440,6 +1442,8 @@ static void
 ocelot_populate_ipv6_ptp_event_trap_key(struct ocelot_vcap_filter *trap)
 {
 	trap->key_type = OCELOT_VCAP_KEY_IPV6;
+	trap->key.ipv4.proto.value[0] = IPPROTO_UDP;
+	trap->key.ipv4.proto.mask[0] = 0xff;
 	trap->key.ipv6.dport.value = PTP_EV_PORT;
 	trap->key.ipv6.dport.mask = 0xffff;
 }
@@ -1448,6 +1452,8 @@ static void
 ocelot_populate_ipv4_ptp_general_trap_key(struct ocelot_vcap_filter *trap)
 {
 	trap->key_type = OCELOT_VCAP_KEY_IPV4;
+	trap->key.ipv4.proto.value[0] = IPPROTO_UDP;
+	trap->key.ipv4.proto.mask[0] = 0xff;
 	trap->key.ipv4.dport.value = PTP_GEN_PORT;
 	trap->key.ipv4.dport.mask = 0xffff;
 }
@@ -1456,6 +1462,8 @@ static void
 ocelot_populate_ipv6_ptp_general_trap_key(struct ocelot_vcap_filter *trap)
 {
 	trap->key_type = OCELOT_VCAP_KEY_IPV6;
+	trap->key.ipv4.proto.value[0] = IPPROTO_UDP;
+	trap->key.ipv4.proto.mask[0] = 0xff;
 	trap->key.ipv6.dport.value = PTP_GEN_PORT;
 	trap->key.ipv6.dport.mask = 0xffff;
 }
-- 
2.25.1

Re: [PATCH net] net: mscc: ocelot: fix all IP traffic getting trapped to CPU with PTP over IP

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (master)
by David S. Miller <davem@davemloft.net>:

On Sat,  5 Feb 2022 01:03:21 +0200 you wrote:
> The filters for the PTP trap keys are incorrectly configured, in the
> sense that is2_entry_set() only looks at trap->key.ipv4.dport or
> trap->key.ipv6.dport if trap->key.ipv4.proto or trap->key.ipv6.proto is
> set to IPPROTO_TCP or IPPROTO_UDP.
> 
> But we don't do that, so is2_entry_set() goes through the "else" branch
> of the IP protocol check, and ends up installing a rule for "Any IP
> protocol match" (because msk is also 0). The UDP port is ignored.
> 
> [...]

Here is the summary with links:
  - [net] net: mscc: ocelot: fix all IP traffic getting trapped to CPU with PTP over IP
    https://git.kernel.org/netdev/net/c/59085208e4a2

You are awesome, thank you!
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