ppp: backport patches improving ppp interface creation

Backport patches improving ppp interface creation. As a side effect this
also fix a bug from using netdev trigger that suffer from LED state
wrongly set due to using old ioctl for ppp creation.

Tested-by: Csaba Sipos <metro4@freemail.hu>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

14 files changed, 1174 insertions, 26 deletions

diff --git a/package/network/services/ppp/Makefile b/package/network/services/ppp/Makefile
index 80d5e46c34..40ec5c5cf1 100644
--- a/package/network/services/ppp/Makefile
+++ b/package/network/services/ppp/Makefile
@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 include $(INCLUDE_DIR)/kernel.mk
 
 PKG_NAME:=ppp
-PKG_RELEASE:=4
+PKG_RELEASE:=5
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL:=https://github.com/paulusmack/ppp
diff --git a/package/network/services/ppp/patches/140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch b/package/network/services/ppp/patches/140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch
new file mode 100644
index 0000000000..154ac7270b
--- /dev/null
+++ b/package/network/services/ppp/patches/140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch
@@ -0,0 +1,54 @@
+From 98ec18f098e5ef68e3a8cc6954fcaf5a7fb8b7be Mon Sep 17 00:00:00 2001
+From: pali <7141871+pali@users.noreply.github.com>
+Date: Mon, 15 Feb 2021 07:54:01 +0100
+Subject: [PATCH] pppd: Fix compilation with older glibc or kernel headers
+ (#248)
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+glibc versions prior to 2.24 do not define SOL_NETLINK and linux kernel
+versions prior to 4.3 do not define NETLINK_CAP_ACK. So add fallback
+definitions for these macros into pppd/sys-linux.c file.
+
+Also extend description why we call SOL_NETLINK/NETLINK_CAP_ACK option.
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+---
+ pppd/sys-linux.c | 18 +++++++++++++++++-
+ 1 file changed, 17 insertions(+), 1 deletion(-)
+
+--- a/pppd/sys-linux.c
++++ b/pppd/sys-linux.c
+@@ -125,6 +125,14 @@
+ #include <linux/netlink.h>
+ #include <linux/rtnetlink.h>
+ #include <linux/if_addr.h>
++/* glibc versions prior to 2.24 do not define SOL_NETLINK */
++#ifndef SOL_NETLINK
++#define SOL_NETLINK 270
++#endif
++/* linux kernel versions prior to 4.3 do not define/support NETLINK_CAP_ACK */
++#ifndef NETLINK_CAP_ACK
++#define NETLINK_CAP_ACK 10
++#endif
+ #endif
+ 
+ #include "pppd.h"
+@@ -2843,7 +2851,15 @@ static int append_peer_ipv6_address(unsi
+     if (fd < 0)
+         return 0;
+ 
+-    /* do not ask for error message content */
++    /*
++     * Tell kernel to not send to us payload of acknowledgment error message.
++     * NETLINK_CAP_ACK option is supported since Linux kernel version 4.3 and
++     * older kernel versions always send full payload in acknowledgment netlink
++     * message. We ignore payload of this message as we need only error code,
++     * to check if our set remote peer address request succeeded or failed.
++     * So ignore return value from the following setsockopt() call as setting
++     * option NETLINK_CAP_ACK means for us just a kernel hint / optimization.
++     */
+     one = 1;
+     setsockopt(fd, SOL_NETLINK, NETLINK_CAP_ACK, &one, sizeof(one));
+ 
diff --git a/package/network/services/ppp/patches/141-Expand-byte-count-statistics-to-64-bits-298.patch b/package/network/services/ppp/patches/141-Expand-byte-count-statistics-to-64-bits-298.patch
new file mode 100644
index 0000000000..e4de5c0aa2
--- /dev/null
+++ b/package/network/services/ppp/patches/141-Expand-byte-count-statistics-to-64-bits-298.patch
@@ -0,0 +1,518 @@
+From 81ad945630120cc1c27c8bb00503be42b76ff202 Mon Sep 17 00:00:00 2001
+From: Jaco Kroon <jaco@uls.co.za>
+Date: Thu, 13 Jan 2022 08:38:04 +0200
+Subject: [PATCH] Expand byte count statistics to 64 bits (#298)
+
+* Add Gigawords to radius packets where applicable.
+
+IMPORTANT NOTE:  The ioctl() only supports 32-bit counters.  In order t
+obtain 64-bit counters, these are now pulled in from sysfs (it's assumed
+to be mounted on /sys which I'm assuming is standard).
+
+It is unknown whether sysfs will be available everywhere, as such, keep
+the ioctl() method in place, but attempt to detect wrap-overs.
+
+If the sysfs mechanism fails, fail back to the ioctl().
+
+Given maximum data rates, the intervals between calling this needs to be
+such that no more than 4GB (2^32) bytes are sent or received in any
+given interval.  Mostly important for radius plugin where data
+accounting may be in effect.
+
+Towards this, a timer interval on 25 seconds is set to force a ioctl()
+poll irrespective of the rate of stats update calls.  This may be
+important for especially radius that needs to provide interim-update
+intervals, if the interim updates is too long and the counters could
+wrap-over twice in a single interval.  At 25 seconds we should detect
+all wraps up to an effective data rate of 1.37Gbps, which for my
+purposes is adequate.
+
+Possible downsides, 4 files are opened, read and closed every time
+statistics is requested.  This results in 12 system calls every single
+time statistics is required, compared to 1 for the ioctl.  Efficiency is
+unknown, but as a rule of thumb fewer system calls are better, this is
+however not a critical path in my opinion, so should not be a problem.
+If required I can run a few benchmarks using gettimeofday() to measure
+actual impact.
+
+Signed-off-by: Jaco Kroon <jaco@uls.co.za>
+
+* Use netlink if possible to obtain 64-bit stats.
+
+This uses two system calls per round.
+
+This should be preferred where available.  It seems the RTM_GETSTATS was
+only added from 2016 some point (4.7.0 as per pali), which is in my
+opinion old, but given experience with certain embedded systems does
+need to be supported.
+
+Signed-off-by: Jaco Kroon <jaco@uls.co.za>
+
+Co-authored-by: Jaco Kroon <jaco@iewc.co.za>
+---
+ pppd/main.c                        |   5 +-
+ pppd/plugins/radius/etc/dictionary |   2 +
+ pppd/plugins/radius/radius.c       |  28 ++-
+ pppd/plugins/radius/radiusclient.h |   2 +
+ pppd/pppd.h                        |   9 +-
+ pppd/sys-linux.c                   | 281 ++++++++++++++++++++++++++++-
+ 6 files changed, 313 insertions(+), 14 deletions(-)
+
+--- a/pppd/main.c
++++ b/pppd/main.c
+@@ -87,6 +87,7 @@
+ #include <sys/socket.h>
+ #include <netinet/in.h>
+ #include <arpa/inet.h>
++#include <inttypes.h>
+ 
+ #include "pppd.h"
+ #include "magic.h"
+@@ -1230,9 +1231,9 @@ update_link_stats(int u)
+ 
+     slprintf(numbuf, sizeof(numbuf), "%u", link_connect_time);
+     script_setenv("CONNECT_TIME", numbuf, 0);
+-    slprintf(numbuf, sizeof(numbuf), "%u", link_stats.bytes_out);
++    snprintf(numbuf, sizeof(numbuf), "%" PRIu64, link_stats.bytes_out);
+     script_setenv("BYTES_SENT", numbuf, 0);
+-    slprintf(numbuf, sizeof(numbuf), "%u", link_stats.bytes_in);
++    snprintf(numbuf, sizeof(numbuf), "%" PRIu64, link_stats.bytes_in);
+     script_setenv("BYTES_RCVD", numbuf, 0);
+ }
+ 
+--- a/pppd/plugins/radius/etc/dictionary
++++ b/pppd/plugins/radius/etc/dictionary
+@@ -82,6 +82,8 @@ ATTRIBUTE	Acct-Session-Time	46	integer
+ ATTRIBUTE	Acct-Input-Packets	47	integer
+ ATTRIBUTE	Acct-Output-Packets	48	integer
+ ATTRIBUTE	Acct-Terminate-Cause	49	integer
++ATTRIBUTE	Acct-Input-Gigawords	52	integer
++ATTRIBUTE	Acct-Output-Gigawords	53	integer
+ ATTRIBUTE       Chap-Challenge          60      string
+ ATTRIBUTE	NAS-Port-Type		61	integer
+ ATTRIBUTE	Port-Limit		62	integer
+--- a/pppd/plugins/radius/radius.c
++++ b/pppd/plugins/radius/radius.c
+@@ -1020,12 +1020,22 @@ radius_acct_stop(void)
+ 	av_type = link_connect_time;
+ 	rc_avpair_add(&send, PW_ACCT_SESSION_TIME, &av_type, 0, VENDOR_NONE);
+ 
+-	av_type = link_stats.bytes_out;
++	av_type = link_stats.bytes_out & 0xFFFFFFFF;
+ 	rc_avpair_add(&send, PW_ACCT_OUTPUT_OCTETS, &av_type, 0, VENDOR_NONE);
+ 
+-	av_type = link_stats.bytes_in;
++	if (link_stats.bytes_out > 0xFFFFFFFF) {
++	    av_type = link_stats.bytes_out >> 32;
++	    rc_avpair_add(&send, PW_ACCT_OUTPUT_GIGAWORDS, &av_type, 0, VENDOR_NONE);
++	}
++
++	av_type = link_stats.bytes_in & 0xFFFFFFFF;
+ 	rc_avpair_add(&send, PW_ACCT_INPUT_OCTETS, &av_type, 0, VENDOR_NONE);
+ 
++	if (link_stats.bytes_in > 0xFFFFFFFF) {
++	    av_type = link_stats.bytes_in >> 32;
++	    rc_avpair_add(&send, PW_ACCT_INPUT_GIGAWORDS, &av_type, 0, VENDOR_NONE);
++	}
++
+ 	av_type = link_stats.pkts_out;
+ 	rc_avpair_add(&send, PW_ACCT_OUTPUT_PACKETS, &av_type, 0, VENDOR_NONE);
+ 
+@@ -1172,12 +1182,22 @@ radius_acct_interim(void *ignored)
+ 	av_type = link_connect_time;
+ 	rc_avpair_add(&send, PW_ACCT_SESSION_TIME, &av_type, 0, VENDOR_NONE);
+ 
+-	av_type = link_stats.bytes_out;
++	av_type = link_stats.bytes_out & 0xFFFFFFFF;
+ 	rc_avpair_add(&send, PW_ACCT_OUTPUT_OCTETS, &av_type, 0, VENDOR_NONE);
+ 
+-	av_type = link_stats.bytes_in;
++	if (link_stats.bytes_out > 0xFFFFFFFF) {
++	    av_type = link_stats.bytes_out >> 32;
++	    rc_avpair_add(&send, PW_ACCT_OUTPUT_GIGAWORDS, &av_type, 0, VENDOR_NONE);
++	}
++
++	av_type = link_stats.bytes_in & 0xFFFFFFFF;
+ 	rc_avpair_add(&send, PW_ACCT_INPUT_OCTETS, &av_type, 0, VENDOR_NONE);
+ 
++	if (link_stats.bytes_in > 0xFFFFFFFF) {
++	    av_type = link_stats.bytes_in >> 32;
++	    rc_avpair_add(&send, PW_ACCT_INPUT_GIGAWORDS, &av_type, 0, VENDOR_NONE);
++	}
++
+ 	av_type = link_stats.pkts_out;
+ 	rc_avpair_add(&send, PW_ACCT_OUTPUT_PACKETS, &av_type, 0, VENDOR_NONE);
+ 
+--- a/pppd/plugins/radius/radiusclient.h
++++ b/pppd/plugins/radius/radiusclient.h
+@@ -184,6 +184,8 @@ typedef struct pw_auth_hdr
+ #define PW_ACCT_LINK_COUNT		51	/* integer */
+ 
+ /* From RFC 2869 */
++#define PW_ACCT_INPUT_GIGAWORDS         52	/* integer */
++#define PW_ACCT_OUTPUT_GIGAWORDS        53	/* integer */
+ #define PW_ACCT_INTERIM_INTERVAL        85	/* integer */
+ 
+ /*	Merit Experimental Extensions */
+--- a/pppd/pppd.h
++++ b/pppd/pppd.h
+@@ -53,6 +53,7 @@
+ #include <stdlib.h>		/* for encrypt */
+ #include <unistd.h>		/* for setkey */
+ #include <stdarg.h>
++#include <stdint.h>
+ #include <limits.h>		/* for NGROUPS_MAX */
+ #include <sys/param.h>		/* for MAXPATHLEN and BSD4_4, if defined */
+ #include <sys/types.h>		/* for u_int32_t, if defined */
+@@ -173,8 +174,8 @@ struct permitted_ip {
+  * pppd needs.
+  */
+ struct pppd_stats {
+-    unsigned int	bytes_in;
+-    unsigned int	bytes_out;
++    uint64_t		bytes_in;
++    uint64_t		bytes_out;
+     unsigned int	pkts_in;
+     unsigned int	pkts_out;
+ };
+@@ -347,7 +348,7 @@ extern char *max_tls_version;
+ extern unsigned int maxoctets;	     /* Maximum octetes per session (in bytes) */
+ extern int       maxoctets_dir;      /* Direction :
+ 				      0 - in+out (default)
+-				      1 - in 
++				      1 - in
+ 				      2 - out
+ 				      3 - max(in,out) */
+ extern int       maxoctets_timeout;  /* Timeout for check of octets limit */
+@@ -356,7 +357,7 @@ extern int       maxoctets_timeout;  /*
+ #define PPP_OCTETS_DIRECTION_OUT        2
+ #define PPP_OCTETS_DIRECTION_MAXOVERAL  3
+ /* same as previos, but little different on RADIUS side */
+-#define PPP_OCTETS_DIRECTION_MAXSESSION 4	
++#define PPP_OCTETS_DIRECTION_MAXSESSION 4
+ #endif
+ 
+ #ifdef PPP_FILTER
+--- a/pppd/sys-linux.c
++++ b/pppd/sys-linux.c
+@@ -79,6 +79,7 @@
+ #include <sys/sysmacros.h>
+ 
+ #include <errno.h>
++#include <stddef.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <syslog.h>
+@@ -92,6 +93,7 @@
+ #include <ctype.h>
+ #include <termios.h>
+ #include <unistd.h>
++#include <limits.h>
+ 
+ /* This is in netdevice.h. However, this compile will fail miserably if
+    you attempt to include netdevice.h because it has so many references
+@@ -121,9 +123,19 @@
+ #include <linux/ppp_defs.h>
+ #include <linux/if_ppp.h>
+ 
+-#ifdef INET6
+ #include <linux/netlink.h>
+ #include <linux/rtnetlink.h>
++#include <linux/if_link.h>
++/* Attempt at retaining compile-support with older than 4.7 kernels, or kernels
++ * where RTM_NEWSTATS isn't defined for whatever reason.
++ */
++#ifndef RTM_NEWSTATS
++#define RTM_NEWSTATS 92
++#define RTM_GETSTATS 94
++#define IFLA_STATS_LINK_64 1
++#endif
++
++#ifdef INET6
+ #include <linux/if_addr.h>
+ /* glibc versions prior to 2.24 do not define SOL_NETLINK */
+ #ifndef SOL_NETLINK
+@@ -1407,11 +1419,17 @@ get_idle_time(int u, struct ppp_idle *ip
+ 
+ /********************************************************************
+  *
+- * get_ppp_stats - return statistics for the link.
++ * get_ppp_stats_iocl - return statistics for the link, using the ioctl() method,
++ * this only supports 32-bit counters, so need to count the wraps.
+  */
+-int
+-get_ppp_stats(int u, struct pppd_stats *stats)
++static int
++get_ppp_stats_ioctl(int u, struct pppd_stats *stats)
+ {
++    static u_int32_t previbytes = 0;
++    static u_int32_t prevobytes = 0;
++    static u_int32_t iwraps = 0;
++    static u_int32_t owraps = 0;
++
+     struct ifpppstatsreq req;
+ 
+     memset (&req, 0, sizeof (req));
+@@ -1426,7 +1444,262 @@ get_ppp_stats(int u, struct pppd_stats *
+     stats->bytes_out = req.stats.p.ppp_obytes;
+     stats->pkts_in = req.stats.p.ppp_ipackets;
+     stats->pkts_out = req.stats.p.ppp_opackets;
++
++    if (stats->bytes_in < previbytes)
++	++iwraps;
++    if (stats->bytes_out < prevobytes)
++	++owraps;
++
++    previbytes = stats->bytes_in;
++    prevobytes = stats->bytes_out;
++
++    stats->bytes_in += (uint64_t)iwraps << 32;
++    stats->bytes_out += (uint64_t)owraps << 32;
++
++    return 1;
++}
++
++/********************************************************************
++ * get_ppp_stats_rtnetlink - return statistics for the link, using rtnetlink
++ * This provides native 64-bit counters.
++ */
++static int
++get_ppp_stats_rtnetlink(int u, struct pppd_stats *stats)
++{
++    static int rtnl_fd = -1;
++
++    struct sockaddr_nl nladdr;
++    struct {
++        struct nlmsghdr nlh;
++        struct if_stats_msg ifsm;
++    } nlreq;
++    struct nlresp {
++        struct nlmsghdr nlh;
++	union {
++	    struct {
++		struct nlmsgerr nlerr;
++		char __end_err[0];
++	    };
++	    struct {
++		struct rtmsg rth;
++		struct  {
++		    /* We only case about these first fields from rtnl_link_stats64 */
++		    uint64_t rx_packets;
++		    uint64_t tx_packets;
++		    uint64_t rx_bytes;
++		    uint64_t tx_bytes;
++		} stats;
++		char __end_stats[0];
++	    };
++	};
++    } nlresp;
++    ssize_t nlresplen;
++    struct iovec iov;
++    struct msghdr msg;
++
++    memset(&nladdr, 0, sizeof(nladdr));
++    nladdr.nl_family = AF_NETLINK;
++
++    if (rtnl_fd < 0) {
++	rtnl_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
++	if (rtnl_fd < 0) {
++	    error("get_ppp_stats_rtnetlink: error creating NETLINK socket: %m (line %d)", __LINE__);
++	    return 0;
++	}
++
++	if (bind(rtnl_fd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0) {
++	    error("get_ppp_stats_rtnetlink: bind(AF_NETLINK): %m (line %d)", __LINE__);
++	    goto err;
++	}
++    }
++
++    memset(&nlreq, 0, sizeof(nlreq));
++    nlreq.nlh.nlmsg_len = sizeof(nlreq);
++    nlreq.nlh.nlmsg_type = RTM_GETSTATS;
++    nlreq.nlh.nlmsg_flags = NLM_F_REQUEST;
++
++    nlreq.ifsm.ifindex = if_nametoindex(ifname);
++    nlreq.ifsm.filter_mask = IFLA_STATS_LINK_64;
++
++    memset(&iov, 0, sizeof(iov));
++    iov.iov_base = &nlreq;
++    iov.iov_len = sizeof(nlreq);
++
++    memset(&msg, 0, sizeof(msg));
++    msg.msg_name = &nladdr;
++    msg.msg_namelen = sizeof(nladdr);
++    msg.msg_iov = &iov;
++    msg.msg_iovlen = 1;
++
++    if (sendmsg(rtnl_fd, &msg, 0) < 0) {
++        error("get_ppp_stats_rtnetlink: sendmsg(RTM_GETSTATS): %m (line %d)", __LINE__);
++	goto err;
++    }
++
++    /* We just need to repoint to IOV ... everything else stays the same */
++    iov.iov_base = &nlresp;
++    iov.iov_len = sizeof(nlresp);
++
++    nlresplen = recvmsg(rtnl_fd, &msg, 0);
++
++    if (nlresplen < 0) {
++        error("get_ppp_stats_rtnetlink: recvmsg(RTM_GETSTATS): %m (line %d)", __LINE__);
++	goto err;
++    }
++
++    if (nlresplen < sizeof(nlresp.nlh)) {
++	error("get_ppp_stats_rtnetlink: Netlink response message was incomplete (line %d)", __LINE__);
++	goto err;
++    }
++
++    if (nlresp.nlh.nlmsg_type == NLMSG_ERROR) {
++	if (nlresplen < offsetof(struct nlresp, __end_err)) {
++	    if (kernel_version >= KVERSION(4,7,0))
++		error("get_ppp_stats_rtnetlink: Netlink responded with error: %s (line %d)", strerror(-nlresp.nlerr.error), __LINE__);
++	} else {
++	    error("get_ppp_stats_rtnetlink: Netlink responded with an error message, but the nlmsgerr structure is incomplete (line %d).",
++		    __LINE__);
++	}
++	goto err;
++    }
++
++    if (nlresp.nlh.nlmsg_type != RTM_NEWSTATS) {
++	error("get_ppp_stats_rtnetlink: Expected RTM_NEWSTATS response, found something else (mlmsg_type %d, line %d)",
++		nlresp.nlh.nlmsg_type, __LINE__);
++	goto err;
++    }
++
++    if (nlresplen < offsetof(struct nlresp, __end_stats)) {
++	error("get_ppp_stats_rtnetlink: Obtained an insufficiently sized rtnl_link_stats64 struct from the kernel (line %d).", __LINE__);
++	goto err;
++    }
++
++    stats->bytes_in  = nlresp.stats.rx_bytes;
++    stats->bytes_out = nlresp.stats.tx_bytes;
++    stats->pkts_in   = nlresp.stats.rx_packets;
++    stats->pkts_out  = nlresp.stats.tx_packets;
++
+     return 1;
++err:
++    close(rtnl_fd);
++    rtnl_fd = -1;
++    return 0;
++}
++
++/********************************************************************
++ * get_ppp_stats_sysfs - return statistics for the link, using the files in sysfs,
++ * this provides native 64-bit counters.
++ */
++static int
++get_ppp_stats_sysfs(int u, struct pppd_stats *stats)
++{
++    char fname[PATH_MAX+1];
++    char buf[21], *err; /* 2^64 < 10^20 */
++    int blen, fd, rlen;
++    unsigned long long val;
++
++    struct {
++	const char* fname;
++	void* ptr;
++	unsigned size;
++    } slist[] = {
++#define statfield(fn, field)	{ .fname = #fn, .ptr = &stats->field, .size = sizeof(stats->field) }
++	statfield(rx_bytes, bytes_in),
++	statfield(tx_bytes, bytes_out),
++	statfield(rx_packets, pkts_in),
++	statfield(tx_packets, pkts_out),
++#undef statfield
++    };
++
++    blen = snprintf(fname, sizeof(fname), "/sys/class/net/%s/statistics/", ifname);
++    if (blen >= sizeof(fname))
++	return 0; /* ifname max 15, so this should be impossible */
++
++    for (int i = 0; i < sizeof(slist) / sizeof(*slist); ++i) {
++	if (snprintf(fname + blen, sizeof(fname) - blen, "%s", slist[i].fname) >= sizeof(fname) - blen) {
++	    fname[blen] = 0;
++	    error("sysfs stats: filename %s/%s overflowed PATH_MAX", fname, slist[i].fname);
++	    return 0;
++	}
++
++	fd = open(fname, O_RDONLY);
++	if (fd < 0) {
++	    error("%s: %m", fname);
++	    return 0;
++	}
++
++	rlen = read(fd, buf, sizeof(buf) - 1);
++	close(fd);
++	if (rlen < 0) {
++	    error("%s: %m", fname);
++	    return 0;
++	}
++	/* trim trailing \n if present */
++	while (rlen > 0 && buf[rlen-1] == '\n')
++	    rlen--;
++	buf[rlen] = 0;
++
++	errno = 0;
++	val = strtoull(buf, &err, 10);
++	if (*buf < '0' || *buf > '9' || errno != 0 || *err) {
++	    error("string to number conversion error converting %s (from %s) for remaining string %s%s%s",
++		    buf, fname, err, errno ? ": " : "", errno ? strerror(errno) : "");
++	    return 0;
++	}
++	switch (slist[i].size) {
++#define stattype(type)	case sizeof(type): *(type*)slist[i].ptr = (type)val; break
++	    stattype(uint64_t);
++	    stattype(uint32_t);
++	    stattype(uint16_t);
++	    stattype(uint8_t);
++#undef stattype
++	default:
++	    error("Don't know how to store stats for %s of size %u", slist[i].fname, slist[i].size);
++	    return 0;
++	}
++    }
++
++    return 1;
++}
++
++/********************************************************************
++ * Periodic timer function to be used to keep stats up to date in case of ioctl
++ * polling.
++ *
++ * Given the 25s interval this should be fine up to data rates of 1.37Gbps.
++ * If you do change the timer, remember to also bring the get_ppp_stats (which
++ * sets up the initial trigger) as well.
++ */
++static void
++ppp_stats_poller(void* u)
++{
++    struct pppd_stats dummy;
++    get_ppp_stats_ioctl((long)u, &dummy);
++    TIMEOUT(ppp_stats_poller, u, 25);
++}
++
++/********************************************************************
++ * get_ppp_stats - return statistics for the link.
++ */
++int get_ppp_stats(int u, struct pppd_stats *stats)
++{
++    static int (*func)(int, struct pppd_stats*) = NULL;
++
++    if (!func) {
++	if (get_ppp_stats_rtnetlink(u, stats)) {
++	    func = get_ppp_stats_rtnetlink;
++	    return 1;
++	}
++	if (get_ppp_stats_sysfs(u, stats)) {
++	    func = get_ppp_stats_sysfs;
++	    return 1;
++	}
++	warn("statistics falling back to ioctl which only supports 32-bit counters");
++	func = get_ppp_stats_ioctl;
++	TIMEOUT(ppp_stats_poller, (void*)(long)u, 25);
++    }
++
++    return func(u, stats);
+ }
+ 
+ /********************************************************************
diff --git a/package/network/services/ppp/patches/142-pppd-Add-support-for-registering-ppp-interface-via-L.patch b/package/network/services/ppp/patches/142-pppd-Add-support-for-registering-ppp-interface-via-L.patch
new file mode 100644
index 0000000000..9987d3dce9
--- /dev/null
+++ b/package/network/services/ppp/patches/142-pppd-Add-support-for-registering-ppp-interface-via-L.patch
@@ -0,0 +1,299 @@
+From 4a54e34cf5629f9fed61f0b7d69ee3ba4d874bc6 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
+Date: Sat, 9 Jul 2022 13:40:24 +0200
+Subject: [PATCH] pppd: Add support for registering ppp interface via Linux
+ rtnetlink API
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+pppd currently creates ppp network interface via PPPIOCNEWUNIT ioctl API.
+This API creates a new ppp network interface named "ppp<unit_id>". If user
+supply option "ifname" with custom network name then pppd calls SIOCSIFNAME
+ioctl to rename "ppp<unit_id>" to custom name immediately after successful
+PPPIOCNEWUNIT ioctl call. If custom name is already registered then
+SIOCSIFNAME ioctl fails and pppd close current channel (which destroy also
+network interface).
+
+This has side effect that in the first few miliseconds interface has
+different name as what user supplied.
+
+Tools like systemd, udev or NetworkManager are trying to query
+interface attributes based on interface name immediately when new
+network interface is created.
+
+But if interface is renamed immediately after creation then these tools
+fails. For example when running pppd with option "ifname ppp-wan" following
+error is reported by systemd / udev into dmesg log:
+
+    [   35.718732] PPP generic driver version 2.4.2
+    [   35.793914] NET: Registered protocol family 24
+    [   35.889924] systemd-udevd[1852]: link_config: autonegotiation is unset or enabled, the speed and duplex are not writable.
+    [   35.901450] ppp-wan: renamed from ppp0
+    [   35.930332] systemd-udevd[1852]: link_config: could not get ethtool features for ppp0
+    [   35.939473] systemd-udevd[1852]: Could not set offload features of ppp0: No such device
+
+There is an easy way to fix this issue: Use new rtnetlink API.
+
+Via rtnetlink API it is possible to create ppp network interface with
+custom ifname atomically. Just it is not possible to specify custom ppp
+unit id.
+
+So use new rtnetlink API when user requested custom ifname without custom
+ppp unit id. This will avoid system issues with interface renaming as ppp
+interface is directly registered with specified final name.
+
+This has also advantage that if requested interface name already exists
+then pppd fail during registering of networking interface and not during
+renaming network interface which happens after successful registration.
+
+If user supply custom ppp unit id then it is required to use old ioctl API
+as currently it is the only API which allows specifying ppp unit id.
+
+When user does not specify custom ifname stay also with old ioctl API.
+There is currently a bug in kernel which cause that when empty interface is
+specified in rtnetlink message for creating ppp interface then kernel
+creates ppp interface but with pseudo-random name, not derived from ppp
+unit id. And therefore it is not possible to retrieve what is the name of
+newly created network interface. So when user does not specify interface
+name via "ifname" option (which means that want from kernel to choose some
+"free" interface name) it is needed to use old ioctl API which do it
+correctly for now.
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+---
+ pppd/sys-linux.c | 194 ++++++++++++++++++++++++++++++++++++++++++++++-
+ 1 file changed, 192 insertions(+), 2 deletions(-)
+
+--- a/pppd/sys-linux.c
++++ b/pppd/sys-linux.c
+@@ -126,6 +126,11 @@
+ #include <linux/netlink.h>
+ #include <linux/rtnetlink.h>
+ #include <linux/if_link.h>
++
++#ifdef INET6
++#include <linux/if_addr.h>
++#endif
++
+ /* Attempt at retaining compile-support with older than 4.7 kernels, or kernels
+  * where RTM_NEWSTATS isn't defined for whatever reason.
+  */
+@@ -135,16 +140,20 @@
+ #define IFLA_STATS_LINK_64 1
+ #endif
+ 
+-#ifdef INET6
+-#include <linux/if_addr.h>
+ /* glibc versions prior to 2.24 do not define SOL_NETLINK */
+ #ifndef SOL_NETLINK
+ #define SOL_NETLINK 270
+ #endif
++
+ /* linux kernel versions prior to 4.3 do not define/support NETLINK_CAP_ACK */
+ #ifndef NETLINK_CAP_ACK
+ #define NETLINK_CAP_ACK 10
+ #endif
++
++/* linux kernel versions prior to 4.7 do not define/support IFLA_PPP_DEV_FD */
++#ifndef IFLA_PPP_MAX
++/* IFLA_PPP_DEV_FD is declared as enum when IFLA_PPP_MAX is defined */
++#define IFLA_PPP_DEV_FD 1
+ #endif
+ 
+ #include "pppd.h"
+@@ -657,6 +666,160 @@ void generic_disestablish_ppp(int dev_fd
+ }
+ 
+ /*
++ * make_ppp_unit_rtnetlink - register a new ppp network interface for ppp_dev_fd
++ * with specified req_ifname via rtnetlink. Interface name req_ifname must not
++ * be empty. Custom ppp unit id req_unit is ignored and kernel choose some free.
++ */
++static int make_ppp_unit_rtnetlink(void)
++{
++    struct {
++        struct nlmsghdr nlh;
++        struct ifinfomsg ifm;
++        struct {
++            struct rtattr rta;
++            char ifname[IFNAMSIZ];
++        } ifn;
++        struct {
++            struct rtattr rta;
++            struct {
++                struct rtattr rta;
++                char ifkind[sizeof("ppp")];
++            } ifik;
++            struct {
++                struct rtattr rta;
++                struct {
++                    struct rtattr rta;
++                    union {
++                        int ppp_dev_fd;
++                    } ppp;
++                } ifdata[1];
++            } ifid;
++        } ifli;
++    } nlreq;
++    struct {
++        struct nlmsghdr nlh;
++        struct nlmsgerr nlerr;
++    } nlresp;
++    struct sockaddr_nl nladdr;
++    struct iovec iov;
++    struct msghdr msg;
++    ssize_t nlresplen;
++    int one;
++    int fd;
++
++    fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
++    if (fd < 0) {
++        error("make_ppp_unit_rtnetlink: socket(NETLINK_ROUTE): %m (line %d)", __LINE__);
++        return 0;
++    }
++
++    /* Tell kernel to not send to us payload of acknowledgment error message. */
++    one = 1;
++    setsockopt(fd, SOL_NETLINK, NETLINK_CAP_ACK, &one, sizeof(one));
++
++    memset(&nladdr, 0, sizeof(nladdr));
++    nladdr.nl_family = AF_NETLINK;
++
++    if (bind(fd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0) {
++        error("make_ppp_unit_rtnetlink: bind(AF_NETLINK): %m (line %d)", __LINE__);
++        close(fd);
++        return 0;
++    }
++
++    memset(&nlreq, 0, sizeof(nlreq));
++    nlreq.nlh.nlmsg_len = sizeof(nlreq);
++    nlreq.nlh.nlmsg_type = RTM_NEWLINK;
++    nlreq.nlh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE;
++    nlreq.ifm.ifi_family = AF_UNSPEC;
++    nlreq.ifm.ifi_type = ARPHRD_NETROM;
++    nlreq.ifn.rta.rta_len = sizeof(nlreq.ifn);
++    nlreq.ifn.rta.rta_type = IFLA_IFNAME;
++    strlcpy(nlreq.ifn.ifname, req_ifname, sizeof(nlreq.ifn.ifname));
++    nlreq.ifli.rta.rta_len = sizeof(nlreq.ifli);
++    nlreq.ifli.rta.rta_type = IFLA_LINKINFO;
++    nlreq.ifli.ifik.rta.rta_len = sizeof(nlreq.ifli.ifik);
++    nlreq.ifli.ifik.rta.rta_type = IFLA_INFO_KIND;
++    strcpy(nlreq.ifli.ifik.ifkind, "ppp");
++    nlreq.ifli.ifid.rta.rta_len = sizeof(nlreq.ifli.ifid);
++    nlreq.ifli.ifid.rta.rta_type = IFLA_INFO_DATA;
++    nlreq.ifli.ifid.ifdata[0].rta.rta_len = sizeof(nlreq.ifli.ifid.ifdata[0]);
++    nlreq.ifli.ifid.ifdata[0].rta.rta_type = IFLA_PPP_DEV_FD;
++    nlreq.ifli.ifid.ifdata[0].ppp.ppp_dev_fd = ppp_dev_fd;
++
++    memset(&nladdr, 0, sizeof(nladdr));
++    nladdr.nl_family = AF_NETLINK;
++
++    memset(&iov, 0, sizeof(iov));
++    iov.iov_base = &nlreq;
++    iov.iov_len = sizeof(nlreq);
++
++    memset(&msg, 0, sizeof(msg));
++    msg.msg_name = &nladdr;
++    msg.msg_namelen = sizeof(nladdr);
++    msg.msg_iov = &iov;
++    msg.msg_iovlen = 1;
++
++    if (sendmsg(fd, &msg, 0) < 0) {
++        error("make_ppp_unit_rtnetlink: sendmsg(RTM_NEWLINK/NLM_F_CREATE): %m (line %d)", __LINE__);
++        close(fd);
++        return 0;
++    }
++
++    memset(&iov, 0, sizeof(iov));
++    iov.iov_base = &nlresp;
++    iov.iov_len = sizeof(nlresp);
++
++    memset(&msg, 0, sizeof(msg));
++    msg.msg_name = &nladdr;
++    msg.msg_namelen = sizeof(nladdr);
++    msg.msg_iov = &iov;
++    msg.msg_iovlen = 1;
++
++    nlresplen = recvmsg(fd, &msg, 0);
++
++    if (nlresplen < 0) {
++        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): %m (line %d)", __LINE__);
++        close(fd);
++        return 0;
++    }
++
++    close(fd);
++
++    if (nladdr.nl_family != AF_NETLINK) {
++        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Not a netlink packet (line %d)", __LINE__);
++        return 0;
++    }
++
++    if ((size_t)nlresplen < sizeof(nlresp) || nlresp.nlh.nlmsg_len < sizeof(nlresp)) {
++        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Acknowledgment netlink packet too short (line %d)", __LINE__);
++        return 0;
++    }
++
++    /* acknowledgment packet for NLM_F_ACK is NLMSG_ERROR */
++    if (nlresp.nlh.nlmsg_type != NLMSG_ERROR) {
++        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Not an acknowledgment netlink packet (line %d)", __LINE__);
++        return 0;
++    }
++
++    /* error == 0 indicates success, negative value is errno code */
++    if (nlresp.nlerr.error != 0) {
++        /*
++         * Linux kernel versions prior to 4.7 do not support creating ppp
++         * interfaces via rtnetlink API and therefore error response is
++         * expected. On older kernel versions do not show this error message.
++         * When error is different than EEXIST then pppd tries to fallback to
++         * the old ioctl method.
++         */
++        errno = (nlresp.nlerr.error < 0) ? -nlresp.nlerr.error : EINVAL;
++        if (kernel_version >= KVERSION(4,7,0))
++            error("Couldn't create ppp interface %s: %m", req_ifname);
++        return 0;
++    }
++
++    return 1;
++}
++
++/*
+  * make_ppp_unit - make a new ppp unit for ppp_dev_fd.
+  * Assumes new_style_driver.
+  */
+@@ -676,6 +839,33 @@ static int make_ppp_unit(void)
+ 	    || fcntl(ppp_dev_fd, F_SETFL, flags | O_NONBLOCK) == -1)
+ 		warn("Couldn't set /dev/ppp to nonblock: %m");
+ 
++	/*
++	 * Via rtnetlink it is possible to create ppp network interface with
++	 * custom ifname atomically. But it is not possible to specify custom
++	 * ppp unit id.
++	 *
++	 * Tools like systemd, udev or NetworkManager are trying to query
++	 * interface attributes based on interface name immediately when new
++	 * network interface is created. And therefore immediate interface
++	 * renaming is causing issues.
++	 *
++	 * So use rtnetlink API only when user requested custom ifname. It will
++	 * avoid system issues with interface renaming.
++	 */
++	if (req_unit == -1 && req_ifname[0] != '\0' && kernel_version >= KVERSION(2,1,16)) {
++	    if (make_ppp_unit_rtnetlink()) {
++		if (ioctl(ppp_dev_fd, PPPIOCGUNIT, &ifunit))
++		    fatal("Couldn't retrieve PPP unit id: %m");
++		return 0;
++	    }
++	    /*
++	     * If interface with requested name already exist return error
++	     * otherwise fallback to old ioctl method.
++	     */
++	    if (errno == EEXIST)
++		return -1;
++	}
++
+ 	ifunit = req_unit;
+ 	x = ioctl(ppp_dev_fd, PPPIOCNEWUNIT, &ifunit);
+ 	if (x < 0 && req_unit >= 0 && errno == EEXIST) {
diff --git a/package/network/services/ppp/patches/143-pppd-Workaround-for-generating-ppp-unit-id-on-Linux-.patch b/package/network/services/ppp/patches/143-pppd-Workaround-for-generating-ppp-unit-id-on-Linux-.patch
new file mode 100644
index 0000000000..abe559e074
--- /dev/null
+++ b/package/network/services/ppp/patches/143-pppd-Workaround-for-generating-ppp-unit-id-on-Linux-.patch
@@ -0,0 +1,59 @@
+From 44609bfc974bdafc0316d069aabf5e2903efa805 Mon Sep 17 00:00:00 2001
+From: pali <7141871+pali@users.noreply.github.com>
+Date: Tue, 9 Aug 2022 11:20:15 +0200
+Subject: [PATCH] pppd: Workaround for generating ppp unit id on Linux (#355)
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Linux kernel has nasty bug / feature. If PPPIOCNEWUNIT is called with
+negative ppp unit id (which is default option when command line argument
+"unit" is not specified; and tells kernel to choose some free ppp unit id)
+and the lowest unused/free ppp unit id is present in some existing network
+interface name prefixed by "ppp" string then this PPPIOCNEWUNIT ioctl
+fails. In this case kernel is basically unable to create a new ppp
+interface via PPPIOCNEWUNIT ioctl when user does not specify some unused
+and non-conflicted unit id.
+
+Linux kernel should be fixed to choose usable ppp unit id when was
+requested via PPPIOCNEWUNIT parameter -1.
+
+Until this happens, add a workaround for pppd to help choosing some random
+ppp unit id when kernel returns this error.
+
+Simple test case (run on system when there is no ppp interface):
+
+    sudo ./pppd ifname ppp1 nodefaultroute noauth nolock local nodetach pty "./pppd nodefaultroute noauth nolock local nodetach notty"
+
+Second pppd process without this patch prints into syslog following error:
+
+    pppd 2.4.10-dev started by pali, uid 0
+    Couldn't create new ppp unit: File exists
+    Exit.
+
+With this patch it falls back to random ppp unit id and succeeds:
+
+    pppd 2.4.10-dev started by pali, uid 0
+    Using interface ppp1361
+    Connect: ppp1361 <--> /dev/pts/14
+    ...
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+---
+ pppd/sys-linux.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+--- a/pppd/sys-linux.c
++++ b/pppd/sys-linux.c
+@@ -873,6 +873,11 @@ static int make_ppp_unit(void)
+ 		ifunit = -1;
+ 		x = ioctl(ppp_dev_fd, PPPIOCNEWUNIT, &ifunit);
+ 	}
++	if (x < 0 && errno == EEXIST) {
++		srand(time(NULL) * getpid());
++		ifunit = rand() % 10000;
++		x = ioctl(ppp_dev_fd, PPPIOCNEWUNIT, &ifunit);
++	}
+ 	if (x < 0)
+ 		error("Couldn't create new ppp unit: %m");
+ 
diff --git a/package/network/services/ppp/patches/144-pppd-Retry-registering-interface-when-on-rtnetlink-E.patch b/package/network/services/ppp/patches/144-pppd-Retry-registering-interface-when-on-rtnetlink-E.patch
new file mode 100644
index 0000000000..26c1e34683
--- /dev/null
+++ b/package/network/services/ppp/patches/144-pppd-Retry-registering-interface-when-on-rtnetlink-E.patch
@@ -0,0 +1,218 @@
+From 089687fbcc6524809ae9f4b2f8145fe3c2a91147 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
+Date: Sat, 7 Aug 2021 19:48:01 +0200
+Subject: [PATCH] pppd: Retry registering interface when on rtnetlink -EBUSY
+ error
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Due to workaround in kernel module ppp_generic.ko in function
+ppp_nl_newlink(), kernel may return -EBUSY error to prevent possible
+mutex deadlock. In this case userspace needs to retry its request.
+
+Proper way would be to fix kernel module to order requests and mutex
+locking, so prevent deadlock in kernel and so never return this error to
+userspace. Until it happens we need retry code in userspace.
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+[ backport to ppp 2.4.9 ]
+Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
+---
+ pppd/sys-linux.c | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+--- a/pppd/sys-linux.c
++++ b/pppd/sys-linux.c
+@@ -707,99 +707,101 @@ static int make_ppp_unit_rtnetlink(void)
+     int one;
+     int fd;
+ 
+-    fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+-    if (fd < 0) {
+-        error("make_ppp_unit_rtnetlink: socket(NETLINK_ROUTE): %m (line %d)", __LINE__);
+-        return 0;
+-    }
+-
+-    /* Tell kernel to not send to us payload of acknowledgment error message. */
+-    one = 1;
+-    setsockopt(fd, SOL_NETLINK, NETLINK_CAP_ACK, &one, sizeof(one));
++    do {
++        fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
++        if (fd < 0) {
++            error("make_ppp_unit_rtnetlink: socket(NETLINK_ROUTE): %m (line %d)", __LINE__);
++            return 0;
++        }
++
++        /* Tell kernel to not send to us payload of acknowledgment error message. */
++        one = 1;
++        setsockopt(fd, SOL_NETLINK, NETLINK_CAP_ACK, &one, sizeof(one));
++
++        memset(&nladdr, 0, sizeof(nladdr));
++        nladdr.nl_family = AF_NETLINK;
++
++        if (bind(fd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0) {
++            error("make_ppp_unit_rtnetlink: bind(AF_NETLINK): %m (line %d)", __LINE__);
++            close(fd);
++            return 0;
++        }
++
++        memset(&nlreq, 0, sizeof(nlreq));
++        nlreq.nlh.nlmsg_len = sizeof(nlreq);
++        nlreq.nlh.nlmsg_type = RTM_NEWLINK;
++        nlreq.nlh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE;
++        nlreq.ifm.ifi_family = AF_UNSPEC;
++        nlreq.ifm.ifi_type = ARPHRD_NETROM;
++        nlreq.ifn.rta.rta_len = sizeof(nlreq.ifn);
++        nlreq.ifn.rta.rta_type = IFLA_IFNAME;
++        strlcpy(nlreq.ifn.ifname, req_ifname, sizeof(nlreq.ifn.ifname));
++        nlreq.ifli.rta.rta_len = sizeof(nlreq.ifli);
++        nlreq.ifli.rta.rta_type = IFLA_LINKINFO;
++        nlreq.ifli.ifik.rta.rta_len = sizeof(nlreq.ifli.ifik);
++        nlreq.ifli.ifik.rta.rta_type = IFLA_INFO_KIND;
++        strcpy(nlreq.ifli.ifik.ifkind, "ppp");
++        nlreq.ifli.ifid.rta.rta_len = sizeof(nlreq.ifli.ifid);
++        nlreq.ifli.ifid.rta.rta_type = IFLA_INFO_DATA;
++        nlreq.ifli.ifid.ifdata[0].rta.rta_len = sizeof(nlreq.ifli.ifid.ifdata[0]);
++        nlreq.ifli.ifid.ifdata[0].rta.rta_type = IFLA_PPP_DEV_FD;
++        nlreq.ifli.ifid.ifdata[0].ppp.ppp_dev_fd = ppp_dev_fd;
++
++        memset(&nladdr, 0, sizeof(nladdr));
++        nladdr.nl_family = AF_NETLINK;
++
++        memset(&iov, 0, sizeof(iov));
++        iov.iov_base = &nlreq;
++        iov.iov_len = sizeof(nlreq);
++
++        memset(&msg, 0, sizeof(msg));
++        msg.msg_name = &nladdr;
++        msg.msg_namelen = sizeof(nladdr);
++        msg.msg_iov = &iov;
++        msg.msg_iovlen = 1;
++
++        if (sendmsg(fd, &msg, 0) < 0) {
++            error("make_ppp_unit_rtnetlink: sendmsg(RTM_NEWLINK/NLM_F_CREATE): %m (line %d)", __LINE__);
++            close(fd);
++            return 0;
++        }
++
++        memset(&iov, 0, sizeof(iov));
++        iov.iov_base = &nlresp;
++        iov.iov_len = sizeof(nlresp);
++
++        memset(&msg, 0, sizeof(msg));
++        msg.msg_name = &nladdr;
++        msg.msg_namelen = sizeof(nladdr);
++        msg.msg_iov = &iov;
++        msg.msg_iovlen = 1;
++
++        nlresplen = recvmsg(fd, &msg, 0);
++
++        if (nlresplen < 0) {
++            error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): %m (line %d)", __LINE__);
++            close(fd);
++            return 0;
++        }
+ 
+-    memset(&nladdr, 0, sizeof(nladdr));
+-    nladdr.nl_family = AF_NETLINK;
+-
+-    if (bind(fd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0) {
+-        error("make_ppp_unit_rtnetlink: bind(AF_NETLINK): %m (line %d)", __LINE__);
+         close(fd);
+-        return 0;
+-    }
+-
+-    memset(&nlreq, 0, sizeof(nlreq));
+-    nlreq.nlh.nlmsg_len = sizeof(nlreq);
+-    nlreq.nlh.nlmsg_type = RTM_NEWLINK;
+-    nlreq.nlh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE;
+-    nlreq.ifm.ifi_family = AF_UNSPEC;
+-    nlreq.ifm.ifi_type = ARPHRD_NETROM;
+-    nlreq.ifn.rta.rta_len = sizeof(nlreq.ifn);
+-    nlreq.ifn.rta.rta_type = IFLA_IFNAME;
+-    strlcpy(nlreq.ifn.ifname, req_ifname, sizeof(nlreq.ifn.ifname));
+-    nlreq.ifli.rta.rta_len = sizeof(nlreq.ifli);
+-    nlreq.ifli.rta.rta_type = IFLA_LINKINFO;
+-    nlreq.ifli.ifik.rta.rta_len = sizeof(nlreq.ifli.ifik);
+-    nlreq.ifli.ifik.rta.rta_type = IFLA_INFO_KIND;
+-    strcpy(nlreq.ifli.ifik.ifkind, "ppp");
+-    nlreq.ifli.ifid.rta.rta_len = sizeof(nlreq.ifli.ifid);
+-    nlreq.ifli.ifid.rta.rta_type = IFLA_INFO_DATA;
+-    nlreq.ifli.ifid.ifdata[0].rta.rta_len = sizeof(nlreq.ifli.ifid.ifdata[0]);
+-    nlreq.ifli.ifid.ifdata[0].rta.rta_type = IFLA_PPP_DEV_FD;
+-    nlreq.ifli.ifid.ifdata[0].ppp.ppp_dev_fd = ppp_dev_fd;
+-
+-    memset(&nladdr, 0, sizeof(nladdr));
+-    nladdr.nl_family = AF_NETLINK;
+-
+-    memset(&iov, 0, sizeof(iov));
+-    iov.iov_base = &nlreq;
+-    iov.iov_len = sizeof(nlreq);
+-
+-    memset(&msg, 0, sizeof(msg));
+-    msg.msg_name = &nladdr;
+-    msg.msg_namelen = sizeof(nladdr);
+-    msg.msg_iov = &iov;
+-    msg.msg_iovlen = 1;
+-
+-    if (sendmsg(fd, &msg, 0) < 0) {
+-        error("make_ppp_unit_rtnetlink: sendmsg(RTM_NEWLINK/NLM_F_CREATE): %m (line %d)", __LINE__);
+-        close(fd);
+-        return 0;
+-    }
+-
+-    memset(&iov, 0, sizeof(iov));
+-    iov.iov_base = &nlresp;
+-    iov.iov_len = sizeof(nlresp);
+-
+-    memset(&msg, 0, sizeof(msg));
+-    msg.msg_name = &nladdr;
+-    msg.msg_namelen = sizeof(nladdr);
+-    msg.msg_iov = &iov;
+-    msg.msg_iovlen = 1;
+-
+-    nlresplen = recvmsg(fd, &msg, 0);
+-
+-    if (nlresplen < 0) {
+-        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): %m (line %d)", __LINE__);
+-        close(fd);
+-        return 0;
+-    }
+-
+-    close(fd);
+ 
+-    if (nladdr.nl_family != AF_NETLINK) {
+-        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Not a netlink packet (line %d)", __LINE__);
+-        return 0;
+-    }
+-
+-    if ((size_t)nlresplen < sizeof(nlresp) || nlresp.nlh.nlmsg_len < sizeof(nlresp)) {
+-        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Acknowledgment netlink packet too short (line %d)", __LINE__);
+-        return 0;
+-    }
+-
+-    /* acknowledgment packet for NLM_F_ACK is NLMSG_ERROR */
+-    if (nlresp.nlh.nlmsg_type != NLMSG_ERROR) {
+-        error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Not an acknowledgment netlink packet (line %d)", __LINE__);
+-        return 0;
+-    }
++        if (nladdr.nl_family != AF_NETLINK) {
++            error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Not a netlink packet (line %d)", __LINE__);
++            return 0;
++        }
++
++        if ((size_t)nlresplen < sizeof(nlresp) || nlresp.nlh.nlmsg_len < sizeof(nlresp)) {
++            error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Acknowledgment netlink packet too short (line %d)", __LINE__);
++            return 0;
++        }
++
++        /* acknowledgment packet for NLM_F_ACK is NLMSG_ERROR */
++        if (nlresp.nlh.nlmsg_type != NLMSG_ERROR) {
++            error("make_ppp_unit_rtnetlink: recvmsg(NLM_F_ACK): Not an acknowledgment netlink packet (line %d)", __LINE__);
++            return 0;
++        }
++    } while (nlresp.nlerr.error == -EBUSY);
+ 
+     /* error == 0 indicates success, negative value is errno code */
+     if (nlresp.nlerr.error != 0) {
diff --git a/package/network/services/ppp/patches/208-fix_status_code.patch b/package/network/services/ppp/patches/208-fix_status_code.patch
index 54e6c45e14..1d991e7949 100644
--- a/package/network/services/ppp/patches/208-fix_status_code.patch
+++ b/package/network/services/ppp/patches/208-fix_status_code.patch
@@ -12,7 +12,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/main.c
 +++ b/pppd/main.c
-@@ -1034,7 +1034,8 @@ get_input(void)
+@@ -1035,7 +1035,8 @@ get_input(void)
  	}
  	notice("Modem hangup");
  	hungup = 1;
diff --git a/package/network/services/ppp/patches/321-multilink_support_custom_iface_names.patch b/package/network/services/ppp/patches/321-multilink_support_custom_iface_names.patch
index 0c4d7ea9d6..0ae84ae1ed 100644
--- a/package/network/services/ppp/patches/321-multilink_support_custom_iface_names.patch
+++ b/package/network/services/ppp/patches/321-multilink_support_custom_iface_names.patch
@@ -119,7 +119,7 @@ Signed-off-by: George Kashperko <george@znau.edu.ua>
  			&& memcmp(vd.dptr, key.dptr, vd.dsize) == 0;
 --- a/pppd/sys-linux.c
 +++ b/pppd/sys-linux.c
-@@ -706,6 +706,16 @@ void cfg_bundle(int mrru, int mtru, int
+@@ -923,6 +923,16 @@ void cfg_bundle(int mrru, int mtru, int
  	add_fd(ppp_dev_fd);
  }
  
@@ -136,7 +136,7 @@ Signed-off-by: George Kashperko <george@znau.edu.ua>
  /*
   * make_new_bundle - create a new PPP unit (i.e. a bundle)
   * and connect our channel to it.  This should only get called
-@@ -724,6 +734,8 @@ void make_new_bundle(int mrru, int mtru,
+@@ -941,6 +951,8 @@ void make_new_bundle(int mrru, int mtru,
  
  	/* set the mrru and flags */
  	cfg_bundle(mrru, mtru, rssn, tssn);
diff --git a/package/network/services/ppp/patches/330-retain_foreign_default_routes.patch b/package/network/services/ppp/patches/330-retain_foreign_default_routes.patch
index 6ccc4507b2..3d2a815dbd 100644
--- a/package/network/services/ppp/patches/330-retain_foreign_default_routes.patch
+++ b/package/network/services/ppp/patches/330-retain_foreign_default_routes.patch
@@ -12,7 +12,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/sys-linux.c
 +++ b/pppd/sys-linux.c
-@@ -1770,6 +1770,7 @@ int cifdefaultroute (int unit, u_int32_t
+@@ -2248,6 +2248,7 @@ int cifdefaultroute (int unit, u_int32_t
  	SIN_ADDR(rt.rt_genmask) = 0L;
      }
  
diff --git a/package/network/services/ppp/patches/340-populate_default_gateway.patch b/package/network/services/ppp/patches/340-populate_default_gateway.patch
index 0f965c705d..64d03fb5c4 100644
--- a/package/network/services/ppp/patches/340-populate_default_gateway.patch
+++ b/package/network/services/ppp/patches/340-populate_default_gateway.patch
@@ -13,7 +13,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/sys-linux.c
 +++ b/pppd/sys-linux.c
-@@ -1720,6 +1720,9 @@ int sifdefaultroute (int unit, u_int32_t
+@@ -2198,6 +2198,9 @@ int sifdefaultroute (int unit, u_int32_t
      memset (&rt, 0, sizeof (rt));
      SET_SA_FAMILY (rt.rt_dst, AF_INET);
  
@@ -23,7 +23,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      rt.rt_dev = ifname;
      rt.rt_metric = dfl_route_metric + 1; /* +1 for binary compatibility */
  
-@@ -1728,7 +1731,7 @@ int sifdefaultroute (int unit, u_int32_t
+@@ -2206,7 +2209,7 @@ int sifdefaultroute (int unit, u_int32_t
  	SIN_ADDR(rt.rt_genmask) = 0L;
      }
  
diff --git a/package/network/services/ppp/patches/400-simplify_kernel_checks.patch b/package/network/services/ppp/patches/400-simplify_kernel_checks.patch
index 3c72048362..9d0ea9a0b8 100644
--- a/package/network/services/ppp/patches/400-simplify_kernel_checks.patch
+++ b/package/network/services/ppp/patches/400-simplify_kernel_checks.patch
@@ -10,7 +10,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/sys-linux.c
 +++ b/pppd/sys-linux.c
-@@ -206,7 +206,7 @@ static int driver_is_old       = 0;
+@@ -235,7 +235,7 @@ static int driver_is_old       = 0;
  static int restore_term        = 0;	/* 1 => we've munged the terminal */
  static struct termios inittermios;	/* Initial TTY termios */
  
@@ -19,7 +19,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
  
  static char loop_name[20];
  static unsigned char inbuf[512]; /* buffer for chars read from loopback */
-@@ -225,8 +225,8 @@ static int	looped;			/* 1 if using loop
+@@ -254,8 +254,8 @@ static int	looped;			/* 1 if using loop
  static int	link_mtu;		/* mtu for the link (not bundle) */
  
  static struct utsname utsname;	/* for the kernel version */
@@ -29,7 +29,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
  
  #define MAX_IFS		100
  
-@@ -1455,11 +1455,12 @@ int ccp_fatal_error (int unit)
+@@ -1933,11 +1933,12 @@ int ccp_fatal_error (int unit)
   *
   * path_to_procfs - find the path to the proc file system mount point
   */
@@ -44,7 +44,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      struct mntent *mntent;
      FILE *fp;
  
-@@ -1481,6 +1482,7 @@ static char *path_to_procfs(const char *
+@@ -1959,6 +1960,7 @@ static char *path_to_procfs(const char *
  	    fclose (fp);
  	}
      }
@@ -52,7 +52,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
  
      strlcpy(proc_path + proc_path_len, tail,
  	    sizeof(proc_path) - proc_path_len);
-@@ -2365,15 +2367,19 @@ int ppp_available(void)
+@@ -2843,15 +2845,19 @@ int ppp_available(void)
      int    my_version, my_modification, my_patch;
      int osmaj, osmin, ospatch;
  
@@ -72,7 +72,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
  
  	/* XXX should get from driver */
  	driver_version = 2;
-@@ -2433,6 +2439,7 @@ int ppp_available(void)
+@@ -2911,6 +2917,7 @@ int ppp_available(void)
  
      if (ok && ((ifr.ifr_hwaddr.sa_family & ~0xFF) != ARPHRD_PPP))
  	ok = 0;
@@ -80,7 +80,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
  
  /*
   *  This is the PPP device. Validate the version of the driver at this
-@@ -3106,6 +3113,7 @@ get_pty(int *master_fdp, int *slave_fdp,
+@@ -3592,6 +3599,7 @@ get_pty(int *master_fdp, int *slave_fdp,
      }
  #endif /* TIOCGPTN */
  
@@ -88,7 +88,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      if (sfd < 0) {
  	/* the old way - scan through the pty name space */
  	for (i = 0; i < 64; ++i) {
-@@ -3124,6 +3132,7 @@ get_pty(int *master_fdp, int *slave_fdp,
+@@ -3610,6 +3618,7 @@ get_pty(int *master_fdp, int *slave_fdp,
  	    }
  	}
      }
diff --git a/package/network/services/ppp/patches/401-no_record_file.patch b/package/network/services/ppp/patches/401-no_record_file.patch
index 7844260685..0304f36fe2 100644
--- a/package/network/services/ppp/patches/401-no_record_file.patch
+++ b/package/network/services/ppp/patches/401-no_record_file.patch
@@ -7,7 +7,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/pppd.h
 +++ b/pppd/pppd.h
-@@ -317,7 +317,6 @@ extern int	holdoff;	/* Dead time before
+@@ -318,7 +318,6 @@ extern int	holdoff;	/* Dead time before
  extern bool	holdoff_specified; /* true if user gave a holdoff value */
  extern bool	notty;		/* Stdin/out is not a tty */
  extern char	*pty_socket;	/* Socket to connect to pty */
diff --git a/package/network/services/ppp/patches/403-no_wtmp.patch b/package/network/services/ppp/patches/403-no_wtmp.patch
index 772620ed72..90c2a8208a 100644
--- a/package/network/services/ppp/patches/403-no_wtmp.patch
+++ b/package/network/services/ppp/patches/403-no_wtmp.patch
@@ -7,7 +7,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/sys-linux.c
 +++ b/pppd/sys-linux.c
-@@ -2503,6 +2503,7 @@ int ppp_available(void)
+@@ -2981,6 +2981,7 @@ int ppp_available(void)
  
  void logwtmp (const char *line, const char *name, const char *host)
  {
@@ -15,7 +15,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      struct utmp ut, *utp;
      pid_t  mypid = getpid();
  #if __GLIBC__ < 2
-@@ -2568,6 +2569,7 @@ void logwtmp (const char *line, const ch
+@@ -3046,6 +3047,7 @@ void logwtmp (const char *line, const ch
  	close (wtmp);
      }
  #endif
diff --git a/package/network/services/ppp/patches/404-remove_obsolete_protocol_names.patch b/package/network/services/ppp/patches/404-remove_obsolete_protocol_names.patch
index b9b6f0e593..8bed425a5b 100644
--- a/package/network/services/ppp/patches/404-remove_obsolete_protocol_names.patch
+++ b/package/network/services/ppp/patches/404-remove_obsolete_protocol_names.patch
@@ -7,7 +7,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 
 --- a/pppd/main.c
 +++ b/pppd/main.c
-@@ -866,14 +866,17 @@ struct protocol_list {
+@@ -867,14 +867,17 @@ struct protocol_list {
      const char	*name;
  } protocol_list[] = {
      { 0x21,	"IP" },
@@ -25,7 +25,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x33,	"Stream Protocol ST-II" },
      { 0x35,	"Banyan Vines" },
      { 0x39,	"AppleTalk EDDP" },
-@@ -887,8 +890,11 @@ struct protocol_list {
+@@ -888,8 +891,11 @@ struct protocol_list {
      { 0x49,	"Serial Data Transport Protocol (PPP-SDTP)" },
      { 0x4b,	"SNA over 802.2" },
      { 0x4d,	"SNA" },
@@ -37,7 +37,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x53,	"Encryption" },
      { 0x55,	"Individual Link Encryption" },
      { 0x57,	"IPv6" },
-@@ -899,12 +905,15 @@ struct protocol_list {
+@@ -900,12 +906,15 @@ struct protocol_list {
      { 0x65,	"RTP IPHC Compressed non-TCP" },
      { 0x67,	"RTP IPHC Compressed UDP 8" },
      { 0x69,	"RTP IPHC Compressed RTP 8" },
@@ -53,7 +53,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x0203,	"IBM Source Routing BPDU" },
      { 0x0205,	"DEC LANBridge100 Spanning Tree" },
      { 0x0207,	"Cisco Discovery Protocol" },
-@@ -916,15 +925,19 @@ struct protocol_list {
+@@ -917,15 +926,19 @@ struct protocol_list {
      { 0x0231,	"Luxcom" },
      { 0x0233,	"Sigma Network Systems" },
      { 0x0235,	"Apple Client Server Protocol" },
@@ -73,7 +73,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x4001,	"Cray Communications Control Protocol" },
      { 0x4003,	"CDPD Mobile Network Registration Protocol" },
      { 0x4005,	"Expand accelerator protocol" },
-@@ -935,8 +948,10 @@ struct protocol_list {
+@@ -936,8 +949,10 @@ struct protocol_list {
      { 0x4023,	"RefTek Protocol" },
      { 0x4025,	"Fibre Channel" },
      { 0x4027,	"EMIT Protocols" },
@@ -84,7 +84,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x8023,	"OSI Network Layer Control Protocol" },
      { 0x8025,	"Xerox NS IDP Control Protocol" },
      { 0x8027,	"DECnet Phase IV Control Protocol" },
-@@ -945,7 +960,9 @@ struct protocol_list {
+@@ -946,7 +961,9 @@ struct protocol_list {
      { 0x8031,	"Bridging NCP" },
      { 0x8033,	"Stream Protocol Control Protocol" },
      { 0x8035,	"Banyan Vines Control Protocol" },
@@ -94,7 +94,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x803f,	"NETBIOS Framing Control Protocol" },
      { 0x8041,	"Cisco Systems Control Protocol" },
      { 0x8043,	"Ascom Timeplex" },
-@@ -954,18 +971,24 @@ struct protocol_list {
+@@ -955,18 +972,24 @@ struct protocol_list {
      { 0x8049,	"Serial Data Control Protocol (PPP-SDCP)" },
      { 0x804b,	"SNA over 802.2 Control Protocol" },
      { 0x804d,	"SNA Control Protocol" },
@@ -119,7 +119,7 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
      { 0x8207,	"Cisco Discovery Protocol Control" },
      { 0x8209,	"Netcs Twin Routing" },
      { 0x820b,	"STP - Control Protocol" },
-@@ -974,24 +997,29 @@ struct protocol_list {
+@@ -975,24 +998,29 @@ struct protocol_list {
      { 0x8281,	"MPLSCP" },
      { 0x8285,	"IEEE p1284.4 standard - Protocol Control" },
      { 0x8287,	"ETSI TETRA TNP1 Control Protocol" },