[PATCH v2 0/3] usbipd: enable tcp keepalive and set its options for accepted connection

[PATCH v2 0/3] usbipd: enable tcp keepalive and set its options for accepted connection

[Vadym Hrynchyshyn]

If usbip client does not close a TCP/IP connection to a daemon
gracefully, the daemon will keep this connection open indefinitely.

The issue is that the client cannot attach this device again
until the device will be rebinded by commands:
"usbip unbind -b ..." and "usbip bind -b ...".

This issue was reported by a user, look for details here 
https://github.com/vadimgrn/usbip-win2/issues/109.

To reproduce this issue, run "usbip attach ..." to attach remote usb 
device and make a hard reset of this PC by pressing Reset button.
usbipd will keep this connection forever and will not allow to
attach this device again until unbind/bind will be executed.

To fix that, enable SO_KEEPALIVE for accepted connection and set keepalive
parameters if corresponding program options are passed.

Vadym Hrynchyshyn (3):
  usbipd: enable SO_KEEPALIVE socket option for accepted connection
  usbipd: add long options to set TCP_KEEPIDLE/TCP_KEEPCNT/TCP_KEEPINTVL
    socket options
  usbipd: use usbip_to_int to simplify usbip_setup_port_number
    implementation

 tools/usb/usbip/configure.ac        | 24 +++++++-
 tools/usb/usbip/src/usbip_network.c | 96 +++++++++++++++++++++++++----
 tools/usb/usbip/src/usbip_network.h | 14 +++++
 tools/usb/usbip/src/usbipd.c        | 58 +++++++++++++++--
 4 files changed, 174 insertions(+), 18 deletions(-)

-- 
2.43.0

[PATCH v2 1/3] usbipd: enable SO_KEEPALIVE socket option for accepted connection

[Vadym Hrynchyshyn]

If usbip client does not close a TCP/IP connection to a daemon
gracefully, the daemon will keep this connection open indefinitely.

The issue is that the client cannot attach this device again
until the device will be rebinded on server side by commands:
usbip unbind -b X-Y
usbip bind -b X-Y

usbip client enables tcp keepalive by calling usbip_net_set_keepalive
from usbip_net_tcp_connect. usbip daemon now enables this socket option
too for accepted connection.

Signed-off-by: Vadym Hrynchyshyn <vadimgrn@gmail.com>
---
 tools/usb/usbip/src/usbipd.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/usb/usbip/src/usbipd.c b/tools/usb/usbip/src/usbipd.c
index 48398a78e88a..d89633d8f799 100644
--- a/tools/usb/usbip/src/usbipd.c
+++ b/tools/usb/usbip/src/usbipd.c
@@ -119,6 +119,7 @@ static int recv_request_import(int sockfd)
 	if (found) {
 		/* should set TCP_NODELAY for usbip */
 		usbip_net_set_nodelay(sockfd);
+		usbip_net_set_keepalive(sockfd);
 
 		/* export device needs a TCP/IP socket descriptor */
 		status = usbip_export_device(edev, sockfd);
-- 
2.43.0

[PATCH v2 2/3] usbipd: add long options to set TCP_KEEPIDLE/TCP_KEEPCNT/TCP_KEEPINTVL socket options

[Vadym Hrynchyshyn]

Add usbip daemon options "--tcp-keepidle SECS", "--tcp-keepcnt CNT",
"--tcp-keepintvl SECS". A user can add these parameters if default
values do not satisfy him/her.

If the option is passed, set corresponding socket option for accepted
connection. For example, if "--tcp-keepidle 60" is passed, call
setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPIDLE, ...).

configure.ac handles presence of these socket options.
If TCP_KEEPIDLE/TCP_KEEPCNT/TCP_KEEPINTVL are not available,
corresponding program options will not be added.

Signed-off-by: Vadym Hrynchyshyn <vadimgrn@gmail.com>
---
 tools/usb/usbip/configure.ac        | 24 +++++++-
 tools/usb/usbip/src/usbip_network.c | 85 +++++++++++++++++++++++++++++
 tools/usb/usbip/src/usbip_network.h | 14 +++++
 tools/usb/usbip/src/usbipd.c        | 59 ++++++++++++++++++--
 4 files changed, 176 insertions(+), 6 deletions(-)

diff --git a/tools/usb/usbip/configure.ac b/tools/usb/usbip/configure.ac
index 8debf934f8b7..439377cfe23b 100644
--- a/tools/usb/usbip/configure.ac
+++ b/tools/usb/usbip/configure.ac
@@ -29,7 +29,7 @@ AC_PROG_MAKE_SET
 AC_HEADER_DIRENT
 AC_HEADER_STDC
 AC_CHECK_HEADERS([arpa/inet.h fcntl.h netdb.h netinet/in.h stdint.h stdlib.h dnl
-		  string.h sys/socket.h syslog.h unistd.h])
+		  string.h sys/socket.h syslog.h unistd.h netinet/tcp.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_INT32_T
@@ -107,5 +107,27 @@ AC_ARG_WITH([fortify],
 			    dnl [ACTION-IF-NOT-GIVEN]
 			    [AC_MSG_RESULT([default])])
 
+AC_MSG_CHECKING([whether tcp keepalive options are available])
+AC_COMPILE_IFELSE(
+	[AC_LANG_PROGRAM(
+		[ #include <sys/socket.h>
+		  #include <arpa/inet.h>
+		  #include <netinet/tcp.h> ],
+		[
+			int n = 0;
+			setsockopt(-1, IPPROTO_TCP, TCP_KEEPIDLE, &n, sizeof(n));
+			setsockopt(-1, IPPROTO_TCP, TCP_KEEPCNT, &n, sizeof(n));
+			setsockopt(-1, IPPROTO_TCP, TCP_KEEPINTVL, &n, sizeof(n));
+		]
+	)],
+	[
+		AC_MSG_RESULT([yes])
+		AC_DEFINE([HAVE_KEEPALIVE_OPTS], [1],
+			  [Define to 1 if TCP_KEEPIDLE/TCP_KEEPCNT/TCP_KEEPINTVL
+			   socket-level options are available.])
+	],
+	[ AC_MSG_RESULT([no]) ],
+)
+
 AC_CONFIG_FILES([Makefile libsrc/Makefile src/Makefile])
 AC_OUTPUT
diff --git a/tools/usb/usbip/src/usbip_network.c b/tools/usb/usbip/src/usbip_network.c
index ed4dc8c14269..15787044a7c9 100644
--- a/tools/usb/usbip/src/usbip_network.c
+++ b/tools/usb/usbip/src/usbip_network.c
@@ -50,6 +50,34 @@ void usbip_setup_port_number(char *arg)
 	info("using port %d (\"%s\")", usbip_port, usbip_port_string);
 }
 
+int usbip_to_int(const char *name, const char *val, int maxval)
+{
+	char *end;
+	long value = strtol(val, &end, 10);
+
+	if (end == val) {
+		err("%s: could not parse '%s' as a decimal integer", name, val);
+		return 0;
+	}
+
+	if (*end != '\0') {
+		err("%s: garbage at end of '%s'", name, val);
+		return 0;
+	}
+
+	if (value <= 0) {
+		err("%s: must be greater than zero, actual %s", name, val);
+		return 0;
+	}
+
+	if (value > maxval) {
+		err("%s: %s is too high, max=%d", name, val, maxval);
+		return 0;
+	}
+
+	return value;
+}
+
 uint32_t usbip_net_pack_uint32_t(int pack, uint32_t num)
 {
 	uint32_t i;
@@ -243,6 +271,63 @@ int usbip_net_set_keepalive(int sockfd)
 	return ret;
 }
 
+#if HAVE_KEEPALIVE_OPTS
+
+int usbip_net_set_keepidle(int sockfd, int seconds)
+{
+	int ret;
+
+	ret = setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPIDLE, &seconds, sizeof(seconds));
+	if (ret < 0)
+		dbg("setsockopt: TCP_KEEPIDLE");
+
+	return ret;
+}
+
+int usbip_net_set_keepcnt(int sockfd, int cnt)
+{
+	int ret;
+
+	ret = setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPCNT, &cnt, sizeof(cnt));
+	if (ret < 0)
+		dbg("setsockopt: TCP_KEEPCNT");
+
+	return ret;
+}
+
+int usbip_net_set_keepintvl(int sockfd, int seconds)
+{
+	int ret;
+
+	ret = setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPINTVL, &seconds, sizeof(seconds));
+	if (ret < 0)
+		dbg("setsockopt: TCP_KEEPINTVL");
+
+	return ret;
+}
+
+#else
+
+int usbip_net_set_keepidle(int, int)
+{
+	dbg("setsockopt: TCP_KEEPIDLE is not supported");
+	return -1;
+}
+
+int usbip_net_set_keepcnt(int, int)
+{
+	dbg("setsockopt: TCP_KEEPCNT is not supported");
+	return -1;
+}
+
+int usbip_net_set_keepintvl(int, int)
+{
+	dbg("setsockopt: TCP_KEEPINTVL is not supported");
+	return -1;
+}
+
+#endif /* HAVE_KEEPALIVE_OPTS */
+
 int usbip_net_set_v6only(int sockfd)
 {
 	const int val = 1;
diff --git a/tools/usb/usbip/src/usbip_network.h b/tools/usb/usbip/src/usbip_network.h
index 83b4c5344f72..9611ddede0cf 100644
--- a/tools/usb/usbip/src/usbip_network.h
+++ b/tools/usb/usbip/src/usbip_network.h
@@ -18,6 +18,17 @@ extern int usbip_port;
 extern char *usbip_port_string;
 void usbip_setup_port_number(char *arg);
 
+/**
+ * usbip_to_int - convert string to positive integer
+ * @name:	name of the @val for logging
+ * @val:	string to convert to integer using base 10
+ * @maxval:	max allowed result value
+ *
+ * Return: positive integer on success, zero if conversion
+ *	   is not possible or value is out of range [1...maxval].
+ */
+int usbip_to_int(const char *name, const char *val, int maxval);
+
 /* ---------------------------------------------------------------------- */
 /* Common header for all the kinds of PDUs. */
 struct op_common {
@@ -172,6 +183,9 @@ int usbip_net_recv_op_common(int sockfd, uint16_t *code, int *status);
 int usbip_net_set_reuseaddr(int sockfd);
 int usbip_net_set_nodelay(int sockfd);
 int usbip_net_set_keepalive(int sockfd);
+int usbip_net_set_keepidle(int sockfd, int seconds);
+int usbip_net_set_keepcnt(int sockfd, int cnt);
+int usbip_net_set_keepintvl(int sockfd, int seconds);
 int usbip_net_set_v6only(int sockfd);
 int usbip_net_tcp_connect(char *hostname, char *port);
 
diff --git a/tools/usb/usbip/src/usbipd.c b/tools/usb/usbip/src/usbipd.c
index d89633d8f799..8d83f870b89c 100644
--- a/tools/usb/usbip/src/usbipd.c
+++ b/tools/usb/usbip/src/usbipd.c
@@ -46,6 +46,10 @@
 
 #define DEFAULT_PID_FILE "/var/run/" PROGNAME ".pid"
 
+static int tcp_keepidle;
+static int tcp_keepcnt;
+static int tcp_keepintvl;
+
 static const char usbip_version_string[] = PACKAGE_STRING;
 
 static const char usbipd_help_string[] =
@@ -75,6 +79,19 @@ static const char usbipd_help_string[] =
 	"	-tPORT, --tcp-port PORT\n"
 	"		Listen on TCP/IP port PORT.\n"
 	"\n"
+#if HAVE_KEEPALIVE_OPTS
+	"	--tcp-keepidle SECONDS\n"
+	"		Number of SECONDS a connection needs to be idle\n"
+	"		before TCP begins sending out keep-alive probes.\n"
+	"\n"
+	"	--tcp-keepcnt PROBES\n"
+	"		Max. number of TCP keep-alive PROBES to send\n"
+	"		before killing the connection.\n"
+	"\n"
+	"	--tcp-keepintvl SECONDS\n"
+	"		Number of SECONDS between TCP keep-alive probes.\n"
+	"\n"
+#endif
 	"	-h, --help\n"
 	"		Print this help.\n"
 	"\n"
@@ -88,6 +105,24 @@ static void usbipd_help(void)
 	printf("%s\n", usbipd_help_string);
 }
 
+static void set_socket_options(int sockfd)
+{
+	/* should set TCP_NODELAY for usbip */
+	usbip_net_set_nodelay(sockfd);
+
+	if (usbip_net_set_keepalive(sockfd) < 0)
+		return;
+
+	if (tcp_keepidle)
+		usbip_net_set_keepidle(sockfd, tcp_keepidle);
+
+	if (tcp_keepcnt)
+		usbip_net_set_keepcnt(sockfd, tcp_keepcnt);
+
+	if (tcp_keepintvl)
+		usbip_net_set_keepintvl(sockfd, tcp_keepintvl);
+}
+
 static int recv_request_import(int sockfd)
 {
 	struct op_import_request req;
@@ -117,9 +152,7 @@ static int recv_request_import(int sockfd)
 	}
 
 	if (found) {
-		/* should set TCP_NODELAY for usbip */
-		usbip_net_set_nodelay(sockfd);
-		usbip_net_set_keepalive(sockfd);
+		set_socket_options(sockfd);
 
 		/* export device needs a TCP/IP socket descriptor */
 		status = usbip_export_device(edev, sockfd);
@@ -586,15 +619,21 @@ static int do_standalone_mode(int daemonize, int ipv4, int ipv6)
 
 int main(int argc, char *argv[])
 {
+	enum { KEEPIDLE = 1, KEEPCNT, KEEPINTVL };
+
 	static const struct option longopts[] = {
 		{ "ipv4",     no_argument,       NULL, '4' },
 		{ "ipv6",     no_argument,       NULL, '6' },
 		{ "daemon",   no_argument,       NULL, 'D' },
-		{ "daemon",   no_argument,       NULL, 'D' },
 		{ "debug",    no_argument,       NULL, 'd' },
 		{ "device",   no_argument,       NULL, 'e' },
 		{ "pid",      optional_argument, NULL, 'P' },
 		{ "tcp-port", required_argument, NULL, 't' },
+#if HAVE_KEEPALIVE_OPTS
+		{ "tcp-keepidle",  required_argument, NULL, KEEPIDLE },
+		{ "tcp-keepcnt",   required_argument, NULL, KEEPCNT },
+		{ "tcp-keepintvl", required_argument, NULL, KEEPINTVL },
+#endif
 		{ "help",     no_argument,       NULL, 'h' },
 		{ "version",  no_argument,       NULL, 'v' },
 		{ NULL,	      0,                 NULL,  0  }
@@ -609,6 +648,7 @@ int main(int argc, char *argv[])
 	int daemonize = 0;
 	int ipv4 = 0, ipv6 = 0;
 	int opt, rc = -1;
+	int longidx = 0;
 
 	pid_file = NULL;
 
@@ -621,7 +661,7 @@ int main(int argc, char *argv[])
 	cmd = cmd_standalone_mode;
 	driver = &host_driver;
 	for (;;) {
-		opt = getopt_long(argc, argv, "46DdeP::t:hv", longopts, NULL);
+		opt = getopt_long(argc, argv, "46DdeP::t:hv", longopts, &longidx);
 
 		if (opt == -1)
 			break;
@@ -654,6 +694,15 @@ int main(int argc, char *argv[])
 		case 'e':
 			driver = &device_driver;
 			break;
+		case KEEPIDLE:
+			tcp_keepidle = usbip_to_int(longopts[longidx].name, optarg, UINT16_MAX);
+			break;
+		case KEEPCNT:
+			tcp_keepcnt = usbip_to_int(longopts[longidx].name, optarg, UINT16_MAX);
+			break;
+		case KEEPINTVL:
+			tcp_keepintvl = usbip_to_int(longopts[longidx].name, optarg, UINT16_MAX);
+			break;
 		case '?':
 			usbipd_help();
 		default:
-- 
2.43.0

[PATCH v2 3/3] usbipd: use usbip_to_int to simplify usbip_setup_port_number implementation

[Vadym Hrynchyshyn]

usbip_to_int function is used for handling arguments of options
--tcp-keepidle,--tcp-keepcnt,--tcp-keepintvl. It is now called
from usbip_setup_port_number to handle tcp port number.
This simplifies its implementation.

Signed-off-by: Vadym Hrynchyshyn <vadimgrn@gmail.com>
---
 tools/usb/usbip/src/usbip_network.c | 25 +++++--------------------
 1 file changed, 5 insertions(+), 20 deletions(-)

diff --git a/tools/usb/usbip/src/usbip_network.c b/tools/usb/usbip/src/usbip_network.c
index 15787044a7c9..26559a11e648 100644
--- a/tools/usb/usbip/src/usbip_network.c
+++ b/tools/usb/usbip/src/usbip_network.c
@@ -26,28 +26,13 @@ char *usbip_port_string = "3240";
 void usbip_setup_port_number(char *arg)
 {
 	dbg("parsing port arg '%s'", arg);
-	char *end;
-	unsigned long int port = strtoul(arg, &end, 10);
-
-	if (end == arg) {
-		err("port: could not parse '%s' as a decimal integer", arg);
-		return;
-	}
+	int port = usbip_to_int("port", arg, UINT16_MAX);
 
-	if (*end != '\0') {
-		err("port: garbage at end of '%s'", arg);
-		return;
+	if (port > 0) {
+		usbip_port = port;
+		usbip_port_string = arg;
+		info("using port %d (\"%s\")", usbip_port, usbip_port_string);
 	}
-
-	if (port > UINT16_MAX) {
-		err("port: %s too high (max=%d)",
-		    arg, UINT16_MAX);
-		return;
-	}
-
-	usbip_port = port;
-	usbip_port_string = arg;
-	info("using port %d (\"%s\")", usbip_port, usbip_port_string);
 }
 
 int usbip_to_int(const char *name, const char *val, int maxval)
-- 
2.43.0

Re: [PATCH v2 0/3] usbipd: enable tcp keepalive and set its options for accepted connection

[Greg KH]

On Fri, May 23, 2025 at 12:07:22PM +0300, Vadym Hrynchyshyn wrote:
> If usbip client does not close a TCP/IP connection to a daemon
> gracefully, the daemon will keep this connection open indefinitely.
> 
> The issue is that the client cannot attach this device again
> until the device will be rebinded by commands:
> "usbip unbind -b ..." and "usbip bind -b ...".
> 
> This issue was reported by a user, look for details here 
> https://github.com/vadimgrn/usbip-win2/issues/109.
> 
> To reproduce this issue, run "usbip attach ..." to attach remote usb 
> device and make a hard reset of this PC by pressing Reset button.
> usbipd will keep this connection forever and will not allow to
> attach this device again until unbind/bind will be executed.
> 
> To fix that, enable SO_KEEPALIVE for accepted connection and set keepalive
> parameters if corresponding program options are passed.
> 
> Vadym Hrynchyshyn (3):
>   usbipd: enable SO_KEEPALIVE socket option for accepted connection
>   usbipd: add long options to set TCP_KEEPIDLE/TCP_KEEPCNT/TCP_KEEPINTVL
>     socket options
>   usbipd: use usbip_to_int to simplify usbip_setup_port_number
>     implementation
> 
>  tools/usb/usbip/configure.ac        | 24 +++++++-
>  tools/usb/usbip/src/usbip_network.c | 96 +++++++++++++++++++++++++----
>  tools/usb/usbip/src/usbip_network.h | 14 +++++
>  tools/usb/usbip/src/usbipd.c        | 58 +++++++++++++++--
>  4 files changed, 174 insertions(+), 18 deletions(-)
> 
> -- 
> 2.43.0
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- This looks like a new version of a previously submitted patch, but you
  did not list below the --- line any changes from the previous version.
  Please read the section entitled "The canonical patch format" in the
  kernel file, Documentation/process/submitting-patches.rst for what
  needs to be done here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
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thanks,

greg k-h's patch email bot