Commit 9b70c362 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'net-fix-passive-tfo-socket-having-invalid-napi-id' 

David Wei says:

====================
net: fix passive TFO socket having invalid NAPI ID

Found a bug where an accepted passive TFO socket returns an invalid NAPI
ID (i.e. 0) from SO_INCOMING_NAPI_ID. Add a selftest for this using
netdevsim and fix the bug.

Patch 1 is a drive-by fix for the lib.sh include in an existing
drivers/net/netdevsim/peer.sh selftest.

Patch 2 adds a test binary for a simple TFO server/client.

Patch 3 adds a selftest for checking that the NAPI ID of a passive TFO
socket is valid. This will currently fail.

Patch 4 adds a fix for the bug.
====================

Link: https://patch.msgid.link/20250617212102.175711-1-dw@davidwei.uk


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents f82727ad dbe0ca8d

net/ipv4/tcp_fastopen.c

+3 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
#include <linux/tcp.h>

#include <linux/rcupdate.h>

#include <net/tcp.h>

#include <net/busy_poll.h>



void tcp_fastopen_init_key_once(struct net *net)

{
@@ -279,6 +280,8 @@ static struct sock *tcp_fastopen_create_child(struct sock *sk, 


	refcount_set(&req->rsk_refcnt, 2);



	sk_mark_napi_id_set(child, skb);



	/* Now finish processing the fastopen child socket. */

	tcp_init_transfer(child, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, skb);

tools/testing/selftests/drivers/net/netdevsim/peer.sh

+2 −1
Original line number Diff line number Diff line 
#!/bin/bash

# SPDX-License-Identifier: GPL-2.0-only



source ../../../net/lib.sh

lib_dir=$(dirname $0)/../../../net

source $lib_dir/lib.sh



NSIM_DEV_1_ID=$((256 + RANDOM % 256))

NSIM_DEV_1_SYS=/sys/bus/netdevsim/devices/netdevsim$NSIM_DEV_1_ID

tools/testing/selftests/net/.gitignore

+1 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ tap 
tcp_fastopen_backup_key

tcp_inq

tcp_mmap

tfo

timestamping

tls

toeplitz

tools/testing/selftests/net/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -110,6 +110,8 @@ TEST_GEN_PROGS += proc_net_pktgen 
TEST_PROGS += lwt_dst_cache_ref_loop.sh

TEST_PROGS += skf_net_off.sh

TEST_GEN_FILES += skf_net_off

TEST_GEN_FILES += tfo

TEST_PROGS += tfo_passive.sh



# YNL files, must be before "include ..lib.mk"

YNL_GEN_FILES := busy_poller netlink-dumps

tools/testing/selftests/net/tfo.c

0 → 100644
+171 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#include <error.h>

#include <fcntl.h>

#include <limits.h>

#include <stdbool.h>

#include <stdint.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <arpa/inet.h>

#include <sys/socket.h>

#include <netinet/tcp.h>

#include <errno.h>



static int cfg_server;

static int cfg_client;

static int cfg_port = 8000;

static struct sockaddr_in6 cfg_addr;

static char *cfg_outfile;



static int parse_address(const char *str, int port, struct sockaddr_in6 *sin6)

{

	int ret;



	sin6->sin6_family = AF_INET6;

	sin6->sin6_port = htons(port);



	ret = inet_pton(sin6->sin6_family, str, &sin6->sin6_addr);

	if (ret != 1) {

		/* fallback to plain IPv4 */

		ret = inet_pton(AF_INET, str, &sin6->sin6_addr.s6_addr32[3]);

		if (ret != 1)

			return -1;



		/* add ::ffff prefix */

		sin6->sin6_addr.s6_addr32[0] = 0;

		sin6->sin6_addr.s6_addr32[1] = 0;

		sin6->sin6_addr.s6_addr16[4] = 0;

		sin6->sin6_addr.s6_addr16[5] = 0xffff;

	}



	return 0;

}



static void run_server(void)

{

	unsigned long qlen = 32;

	int fd, opt, connfd;

	socklen_t len;

	char buf[64];

	FILE *outfile;



	outfile = fopen(cfg_outfile, "w");

	if (!outfile)

		error(1, errno, "fopen() outfile");



	fd = socket(AF_INET6, SOCK_STREAM, 0);

	if (fd == -1)

		error(1, errno, "socket()");



	opt = 1;

	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)) < 0)

		error(1, errno, "setsockopt(SO_REUSEADDR)");



	if (setsockopt(fd, SOL_TCP, TCP_FASTOPEN, &qlen, sizeof(qlen)) < 0)

		error(1, errno, "setsockopt(TCP_FASTOPEN)");



	if (bind(fd, (struct sockaddr *)&cfg_addr, sizeof(cfg_addr)) < 0)

		error(1, errno, "bind()");



	if (listen(fd, 5) < 0)

		error(1, errno, "listen()");



	len = sizeof(cfg_addr);

	connfd = accept(fd, (struct sockaddr *)&cfg_addr, &len);

	if (connfd < 0)

		error(1, errno, "accept()");



	len = sizeof(opt);

	if (getsockopt(connfd, SOL_SOCKET, SO_INCOMING_NAPI_ID, &opt, &len) < 0)

		error(1, errno, "getsockopt(SO_INCOMING_NAPI_ID)");



	read(connfd, buf, 64);

	fprintf(outfile, "%d\n", opt);



	fclose(outfile);

	close(connfd);

	close(fd);

}



static void run_client(void)

{

	int fd;

	char *msg = "Hello, world!";



	fd = socket(AF_INET6, SOCK_STREAM, 0);

	if (fd == -1)

		error(1, errno, "socket()");



	sendto(fd, msg, strlen(msg), MSG_FASTOPEN, (struct sockaddr *)&cfg_addr, sizeof(cfg_addr));



	close(fd);

}



static void usage(const char *filepath)

{

	error(1, 0, "Usage: %s (-s|-c) -h<server_ip> -p<port> -o<outfile> ", filepath);

}



static void parse_opts(int argc, char **argv)

{

	struct sockaddr_in6 *addr6 = (void *) &cfg_addr;

	char *addr = NULL;

	int ret;

	int c;



	if (argc <= 1)

		usage(argv[0]);



	while ((c = getopt(argc, argv, "sch:p:o:")) != -1) {

		switch (c) {

		case 's':

			if (cfg_client)

				error(1, 0, "Pass one of -s or -c");

			cfg_server = 1;

			break;

		case 'c':

			if (cfg_server)

				error(1, 0, "Pass one of -s or -c");

			cfg_client = 1;

			break;

		case 'h':

			addr = optarg;

			break;

		case 'p':

			cfg_port = strtoul(optarg, NULL, 0);

			break;

		case 'o':

			cfg_outfile = strdup(optarg);

			if (!cfg_outfile)

				error(1, 0, "outfile invalid");

			break;

		}

	}



	if (cfg_server && addr)

		error(1, 0, "Server cannot have -h specified");



	memset(addr6, 0, sizeof(*addr6));

	addr6->sin6_family = AF_INET6;

	addr6->sin6_port = htons(cfg_port);

	addr6->sin6_addr = in6addr_any;

	if (addr) {

		ret = parse_address(addr, cfg_port, addr6);

		if (ret)

			error(1, 0, "Client address parse error: %s", addr);

	}

}



int main(int argc, char **argv)

{

	parse_opts(argc, argv);



	if (cfg_server)

		run_server();

	else if (cfg_client)

		run_client();



	return 0;

}