[RFC PATCH net-next v6 2/2] selftests: net: test PPPoE packets in gro.sh

Qingfang Deng
2026-03-26T08:11:46Z

Add PPPoE test-cases to the GRO selftest.

Signed-off-by: Qingfang Deng <dqfext@gmail.com>
---
v6: new patch

I'm not sure if I should include all the existing IPv4/v6 tests for
PPPoE. There are tests that hardcode ETH_HLEN as the NH offset, which
are meant to test the L3 protocol, not the underlying protocol, and
changing all of them seems too invasive.

Comments welcome, thanks.
---
tools/testing/selftests/drivers/net/config | 2 +
tools/testing/selftests/drivers/net/gro.py | 25 +++++-
tools/testing/selftests/net/lib/gro.c | 97 ++++++++++++++++------
3 files changed, 98 insertions(+), 26 deletions(-)

diff --git a/tools/testing/selftests/drivers/net/config b/tools/testing/selftests/drivers/net/config
index 77ccf83d87e0..caaba209ba3e 100644
--- a/tools/testing/selftests/drivers/net/config
+++ b/tools/testing/selftests/drivers/net/config
@@ -7,4 +7,6 @@ CONFIG_NETCONSOLE=m
CONFIG_NETCONSOLE_DYNAMIC=y
CONFIG_NETCONSOLE_EXTENDED_LOG=y
CONFIG_NETDEVSIM=m
+CONFIG_PPP=y
+CONFIG_PPPOE=y
CONFIG_XDP_SOCKETS=y
diff --git a/tools/testing/selftests/drivers/net/gro.py b/tools/testing/selftests/drivers/net/gro.py
index 70709bf670c7..eb8306a8f4c4 100755
--- a/tools/testing/selftests/drivers/net/gro.py
+++ b/tools/testing/selftests/drivers/net/gro.py
@@ -186,8 +186,17 @@ def _run_gro_bin(cfg, test_name, protocol=None, num_flows=None,

dmac = _resolve_dmac(cfg, ipver)

- base_args = [
- f"--{protocol}",
+ if protocol.startswith("pppoe"):
+ base_args = [
+ f"--ipv{protocol[-1]}",
+ "--pppoe",
+ ]
+ else:
+ base_args = [
+ f"--{protocol}",
+ ]
+
+ base_args += [
f"--dmac {dmac}",
f"--smac {cfg.remote_dev['address']}",
f"--daddr {cfg.addr_v[ipver]}",
@@ -322,6 +331,18 @@ def _gro_variants():
for test_name in ipv6_tests:
yield mode, protocol, test_name

+ for mode in ["sw"]:
+ for protocol in ["pppoev4", "pppoev6"]:
+ for test_name in common_tests:
+ yield mode, protocol, test_name
+
+ if protocol == "pppoev4":
+ for test_name in ipv4_tests:
+ yield mode, protocol, test_name
+ elif protocol == "pppoev6":
+ for test_name in ipv6_tests:
+ yield mode, protocol, test_name
+

@ksft_variants(_gro_variants())
def test(cfg, mode, protocol, test_name):
diff --git a/tools/testing/selftests/net/lib/gro.c b/tools/testing/selftests/net/lib/gro.c
index 3e611ae25f61..6148bcdff478 100644
--- a/tools/testing/selftests/net/lib/gro.c
+++ b/tools/testing/selftests/net/lib/gro.c
@@ -64,12 +64,14 @@
#include <errno.h>
#include <error.h>
#include <getopt.h>
+#include <net/ethernet.h>
+#include <net/if.h>
#include <linux/filter.h>
#include <linux/if_packet.h>
+#include <linux/if_pppox.h>
#include <linux/ipv6.h>
#include <linux/net_tstamp.h>
-#include <net/ethernet.h>
-#include <net/if.h>
+#include <linux/ppp_defs.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
@@ -92,11 +94,11 @@
#define START_SEQ 100
#define START_ACK 100
#define ETH_P_NONE 0
-#define TOTAL_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
+#define TOTAL_HDR_LEN (ETH_HLEN + PPPOE_SES_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
#define MSS (4096 - sizeof(struct tcphdr) - sizeof(struct ipv6hdr))
#define MAX_PAYLOAD (IP_MAXPACKET - sizeof(struct tcphdr) - sizeof(struct ipv6hdr))
#define NUM_LARGE_PKT (MAX_PAYLOAD / MSS)
-#define MAX_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
+#define MAX_HDR_LEN (ETH_HLEN + PPPOE_SES_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
#define MIN_EXTHDR_SIZE 8
#define EXT_PAYLOAD_1 "\x00\x00\x00\x00\x00\x00"
#define EXT_PAYLOAD_2 "\x11\x11\x11\x11\x11\x11"
@@ -129,6 +131,7 @@ static int tcp_offset = -1;
static int total_hdr_len = -1;
static int ethhdr_proto = -1;
static bool ipip;
+static bool pppoe;
static uint64_t txtime_ns;
static int num_flows = 4;
static bool order_check;
@@ -148,12 +151,37 @@ static void vlog(const char *fmt, ...)
}
}

+static void fill_pppoelayer(void *buf, int payload_len)
+{
+ struct pppoe_ppp_hdr {
+ struct pppoe_hdr eh;
+ __be16 proto;
+ } *ph = buf;
+ int ppp_payload_len;
+
+ ph->eh.type = 1;
+ ph->eh.ver = 1;
+ ph->eh.code = 0;
+ ph->eh.sid = htons(0x1234);
+
+ if (proto == PF_INET6) {
+ ph->proto = htons(PPP_IPV6);
+ ppp_payload_len = sizeof(struct ipv6hdr) + sizeof(struct tcphdr) + payload_len;
+ } else {
+ ph->proto = htons(PPP_IP);
+ ppp_payload_len = sizeof(struct iphdr) + sizeof(struct tcphdr) + payload_len;
+ }
+
+ ph->eh.length = htons(ppp_payload_len + sizeof(ph->proto));
+}
+
static void setup_sock_filter(int fd)
{
const int dport_off = tcp_offset + offsetof(struct tcphdr, dest);
const int ethproto_off = offsetof(struct ethhdr, h_proto);
int optlen = 0;
int ipproto_off, opt_ipproto_off;
+ int head_len = ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0);
int next_off;

if (ipip)
@@ -162,7 +190,7 @@ static void setup_sock_filter(int fd)
next_off = offsetof(struct iphdr, protocol);
else
next_off = offsetof(struct ipv6hdr, nexthdr);
- ipproto_off = ETH_HLEN + next_off;
+ ipproto_off = head_len + next_off;

/* Overridden later if exthdrs are used: */
opt_ipproto_off = ipproto_off;
@@ -178,7 +206,7 @@ static void setup_sock_filter(int fd)

/* same size for HBH and Fragment extension header types */
optlen = MIN_EXTHDR_SIZE;
- opt_ipproto_off = ETH_HLEN + sizeof(struct ipv6hdr)
+ opt_ipproto_off = head_len + sizeof(struct ipv6hdr)
+ offsetof(struct ip6_ext, ip6e_nxt);
}

@@ -390,6 +418,10 @@ static void create_packet(void *buf, int seq_offset, int ack_offset,
IPPROTO_IPIP);
fill_networklayer(buf + ETH_HLEN + sizeof(struct iphdr),
payload_len, IPPROTO_TCP);
+ } else if (pppoe) {
+ fill_pppoelayer(buf + ETH_HLEN, payload_len);
+ fill_networklayer(buf + ETH_HLEN + PPPOE_SES_HLEN,
+ payload_len, IPPROTO_TCP);
} else {
fill_networklayer(buf + ETH_HLEN, payload_len, IPPROTO_TCP);
}
@@ -501,7 +533,7 @@ static void send_flags(int fd, struct sockaddr_ll *daddr, int psh, int syn,
static void send_data_pkts(int fd, struct sockaddr_ll *daddr,
int payload_len1, int payload_len2)
{
- static char buf[ETH_HLEN + IP_MAXPACKET];
+ static char buf[ETH_HLEN + PPPOE_SES_HLEN + IP_MAXPACKET];

create_packet(buf, 0, 0, payload_len1, 0);
write_packet(fd, buf, total_hdr_len + payload_len1, daddr);
@@ -745,7 +777,7 @@ static void add_ipv4_ts_option(void *buf, void *optpkt)
memcpy(optpkt + tcp_offset + optlen, buf + tcp_offset,
sizeof(struct tcphdr) + PAYLOAD_LEN);

- iph = (struct iphdr *)(optpkt + ETH_HLEN);
+ iph = (struct iphdr *)(optpkt + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));
iph->ihl = 5 + (optlen / 4);
iph->tot_len = htons(ntohs(iph->tot_len) + optlen);
iph->check = 0;
@@ -755,7 +787,7 @@ static void add_ipv4_ts_option(void *buf, void *optpkt)
static void add_ipv6_exthdr(void *buf, void *optpkt, __u8 exthdr_type, char *ext_payload)
{
struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr *)(optpkt + tcp_offset);
- struct ipv6hdr *iph = (struct ipv6hdr *)(optpkt + ETH_HLEN);
+ struct ipv6hdr *iph = (struct ipv6hdr *)(optpkt + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));
char *exthdr_payload_start = (char *)(exthdr + 1);

exthdr->hdrlen = 0;
@@ -908,7 +940,7 @@ static void send_ip_options(int fd, struct sockaddr_ll *daddr)
static void send_fragment4(int fd, struct sockaddr_ll *daddr)
{
static char buf[IP_MAXPACKET];
- struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
+ struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));
int pkt_size = total_hdr_len + PAYLOAD_LEN;

create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
@@ -920,7 +952,8 @@ static void send_fragment4(int fd, struct sockaddr_ll *daddr)
*/
memset(buf + total_hdr_len, 'a', PAYLOAD_LEN * 2);
fill_transportlayer(buf + tcp_offset, PAYLOAD_LEN, 0, PAYLOAD_LEN * 2, 0);
- fill_networklayer(buf + ETH_HLEN, PAYLOAD_LEN, IPPROTO_TCP);
+ fill_networklayer(buf + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0),
+ PAYLOAD_LEN, IPPROTO_TCP);
fill_datalinklayer(buf);

iph->frag_off = htons(0x6000); // DF = 1, MF = 1
@@ -934,7 +967,7 @@ static void send_changed_ttl(int fd, struct sockaddr_ll *daddr)
{
int pkt_size = total_hdr_len + PAYLOAD_LEN;
static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
- struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
+ struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));

create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
write_packet(fd, buf, pkt_size, daddr);
@@ -951,8 +984,8 @@ static void send_changed_tos(int fd, struct sockaddr_ll *daddr)
{
int pkt_size = total_hdr_len + PAYLOAD_LEN;
static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
- struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
- struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN);
+ struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));
+ struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));

create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
write_packet(fd, buf, pkt_size, daddr);
@@ -980,7 +1013,8 @@ static void send_changed_ECN(int fd, struct sockaddr_ll *daddr)

create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
if (proto == PF_INET) {
- buf[ETH_HLEN + 1] ^= 0x2; // ECN set to 10
+ int ecn_off = ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0) + 1;
+ buf[ecn_off] ^= 0x2; // ECN set to 10
iph->check = 0;
iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
} else {
@@ -995,7 +1029,7 @@ static void send_fragment6(int fd, struct sockaddr_ll *daddr)
static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
static char extpkt[MAX_HDR_LEN + PAYLOAD_LEN +
sizeof(struct ip6_frag)];
- struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN);
+ struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0));
struct ip6_frag *frag = (void *)(extpkt + tcp_offset);
int extlen = sizeof(struct ip6_frag);
int bufpkt_len = total_hdr_len + PAYLOAD_LEN;
@@ -1073,9 +1107,10 @@ static void recv_error(int fd, int rcv_errno)
static void check_recv_pkts(int fd, int *correct_payload,
int correct_num_pkts)
{
- static char buffer[IP_MAXPACKET + ETH_HLEN + 1];
- struct iphdr *iph = (struct iphdr *)(buffer + ETH_HLEN);
- struct ipv6hdr *ip6h = (struct ipv6hdr *)(buffer + ETH_HLEN);
+ static char buffer[IP_MAXPACKET + ETH_HLEN + PPPOE_SES_HLEN + 1];
+ int nhoff = ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0);
+ struct iphdr *iph = (struct iphdr *)(buffer + nhoff);
+ struct ipv6hdr *ip6h = (struct ipv6hdr *)(buffer + nhoff);
struct tcphdr *tcph;
bool bad_packet = false;
int tcp_ext_len = 0;
@@ -1092,7 +1127,7 @@ static void check_recv_pkts(int fd, int *correct_payload,

while (1) {
ip_ext_len = 0;
- pkt_size = recv(fd, buffer, IP_MAXPACKET + ETH_HLEN + 1, 0);
+ pkt_size = recv(fd, buffer, sizeof(buffer), 0);
if (pkt_size < 0)
recv_error(fd, errno);

@@ -1134,9 +1169,10 @@ static void check_recv_pkts(int fd, int *correct_payload,

static void check_capacity_pkts(int fd)
{
- static char buffer[IP_MAXPACKET + ETH_HLEN + 1];
- struct iphdr *iph = (struct iphdr *)(buffer + ETH_HLEN);
- struct ipv6hdr *ip6h = (struct ipv6hdr *)(buffer + ETH_HLEN);
+ static char buffer[IP_MAXPACKET + ETH_HLEN + PPPOE_SES_HLEN + 1];
+ int nhoff = ETH_HLEN + (pppoe ? PPPOE_SES_HLEN : 0);
+ struct iphdr *iph = (struct iphdr *)(buffer + nhoff);
+ struct ipv6hdr *ip6h = (struct ipv6hdr *)(buffer + nhoff);
int num_pkt = 0, num_coal = 0, pkt_idx;
const char *fail_reason = NULL;
int flow_order[num_flows * 2];
@@ -1154,7 +1190,7 @@ static void check_capacity_pkts(int fd)

while (total_data < num_flows * CAPACITY_PAYLOAD_LEN * 2) {
ip_ext_len = 0;
- pkt_size = recv(fd, buffer, IP_MAXPACKET + ETH_HLEN + 1, 0);
+ pkt_size = recv(fd, buffer, sizeof(buffer), 0);
if (pkt_size < 0)
recv_error(fd, errno);

@@ -1645,6 +1681,7 @@ static void parse_args(int argc, char **argv)
{ "ipv4", no_argument, NULL, '4' },
{ "ipv6", no_argument, NULL, '6' },
{ "ipip", no_argument, NULL, 'e' },
+ { "pppoe", no_argument, NULL, 'p' },
{ "num-flows", required_argument, NULL, 'n' },
{ "rx", no_argument, NULL, 'r' },
{ "saddr", required_argument, NULL, 's' },
@@ -1671,6 +1708,9 @@ static void parse_args(int argc, char **argv)
proto = PF_INET;
ethhdr_proto = htons(ETH_P_IP);
break;
+ case 'p':
+ pppoe = true;
+ break;
case 'd':
addr4_dst = addr6_dst = optarg;
break;
@@ -1715,6 +1755,15 @@ int main(int argc, char **argv)
if (ipip) {
tcp_offset = ETH_HLEN + sizeof(struct iphdr) * 2;
total_hdr_len = tcp_offset + sizeof(struct tcphdr);
+ } else if (pppoe) {
+ if (proto == PF_INET)
+ tcp_offset = ETH_HLEN + PPPOE_SES_HLEN + sizeof(struct iphdr);
+ else if (proto == PF_INET6)
+ tcp_offset = ETH_HLEN + PPPOE_SES_HLEN + sizeof(struct ipv6hdr);
+ else
+ error(1, 0, "Protocol family is not ipv4 or ipv6");
+ total_hdr_len = tcp_offset + sizeof(struct tcphdr);
+ ethhdr_proto = htons(ETH_P_PPP_SES);
} else if (proto == PF_INET) {
tcp_offset = ETH_HLEN + sizeof(struct iphdr);
total_hdr_len = tcp_offset + sizeof(struct tcphdr);
--
2.43.0