From 8ac6c7a54ed1b98d142dce24b11c6de6a1e239a5 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 22 Oct 2024 10:36:11 +0000
Subject: [PATCH] 修改4g拨号为QMI,需要在系统里后台执行quectel-CM

---
 kernel/net/ipv6/ip6_flowlabel.c |  364 +++++++++++++++++++++++++++++----------------------
 1 files changed, 204 insertions(+), 160 deletions(-)

diff --git a/kernel/net/ipv6/ip6_flowlabel.c b/kernel/net/ipv6/ip6_flowlabel.c
index f994f50..aa673a6 100644
--- a/kernel/net/ipv6/ip6_flowlabel.c
+++ b/kernel/net/ipv6/ip6_flowlabel.c
@@ -1,10 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	ip6_flowlabel.c		IPv6 flowlabel manager.
- *
- *	This program is free software; you can redistribute it and/or
- *      modify it under the terms of the GNU General Public License
- *      as published by the Free Software Foundation; either version
- *      2 of the License, or (at your option) any later version.
  *
  *	Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  */
@@ -21,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/export.h>
 #include <linux/pid_namespace.h>
+#include <linux/jump_label_ratelimit.h>
 
 #include <net/net_namespace.h>
 #include <net/sock.h>
@@ -56,6 +53,9 @@
 /* Big socket sock */
 
 static DEFINE_SPINLOCK(ip6_sk_fl_lock);
+
+DEFINE_STATIC_KEY_DEFERRED_FALSE(ipv6_flowlabel_exclusive, HZ);
+EXPORT_SYMBOL(ipv6_flowlabel_exclusive);
 
 #define for_each_fl_rcu(hash, fl)				\
 	for (fl = rcu_dereference_bh(fl_ht[(hash)]);		\
@@ -94,6 +94,13 @@
 	return fl;
 }
 
+static bool fl_shared_exclusive(struct ip6_flowlabel *fl)
+{
+	return fl->share == IPV6_FL_S_EXCL ||
+	       fl->share == IPV6_FL_S_PROCESS ||
+	       fl->share == IPV6_FL_S_USER;
+}
+
 static void fl_free_rcu(struct rcu_head *head)
 {
 	struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu);
@@ -107,8 +114,13 @@
 
 static void fl_free(struct ip6_flowlabel *fl)
 {
-	if (fl)
-		call_rcu(&fl->rcu, fl_free_rcu);
+	if (!fl)
+		return;
+
+	if (fl_shared_exclusive(fl) || fl->opt)
+		static_branch_slow_dec_deferred(&ipv6_flowlabel_exclusive);
+
+	call_rcu(&fl->rcu, fl_free_rcu);
 }
 
 static void fl_release(struct ip6_flowlabel *fl)
@@ -244,7 +256,7 @@
 
 /* Socket flowlabel lists */
 
-struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label)
+struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label)
 {
 	struct ipv6_fl_socklist *sfl;
 	struct ipv6_pinfo *np = inet6_sk(sk);
@@ -264,7 +276,7 @@
 	rcu_read_unlock_bh();
 	return NULL;
 }
-EXPORT_SYMBOL_GPL(fl6_sock_lookup);
+EXPORT_SYMBOL_GPL(__fl6_sock_lookup);
 
 void fl6_free_socklist(struct sock *sk)
 {
@@ -359,7 +371,7 @@
 
 static struct ip6_flowlabel *
 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq,
-	  char __user *optval, int optlen, int *err_p)
+	  sockptr_t optval, int optlen, int *err_p)
 {
 	struct ip6_flowlabel *fl = NULL;
 	int olen;
@@ -389,7 +401,8 @@
 		memset(fl->opt, 0, sizeof(*fl->opt));
 		fl->opt->tot_len = sizeof(*fl->opt) + olen;
 		err = -EFAULT;
-		if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
+		if (copy_from_sockptr_offset(fl->opt + 1, optval,
+				CMSG_ALIGN(sizeof(*freq)), olen))
 			goto done;
 
 		msg.msg_controllen = olen;
@@ -437,10 +450,15 @@
 		err = -EINVAL;
 		goto done;
 	}
+	if (fl_shared_exclusive(fl) || fl->opt)
+		static_branch_deferred_inc(&ipv6_flowlabel_exclusive);
 	return fl;
 
 done:
-	fl_free(fl);
+	if (fl) {
+		kfree(fl->opt);
+		kfree(fl);
+	}
 	*err_p = err;
 	return NULL;
 }
@@ -516,185 +534,210 @@
 	return -ENOENT;
 }
 
-int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
+#define socklist_dereference(__sflp) \
+	rcu_dereference_protected(__sflp, lockdep_is_held(&ip6_sk_fl_lock))
+
+static int ipv6_flowlabel_put(struct sock *sk, struct in6_flowlabel_req *freq)
 {
-	int uninitialized_var(err);
-	struct net *net = sock_net(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
-	struct in6_flowlabel_req freq;
-	struct ipv6_fl_socklist *sfl1 = NULL;
-	struct ipv6_fl_socklist *sfl;
 	struct ipv6_fl_socklist __rcu **sflp;
+	struct ipv6_fl_socklist *sfl;
+
+	if (freq->flr_flags & IPV6_FL_F_REFLECT) {
+		if (sk->sk_protocol != IPPROTO_TCP)
+			return -ENOPROTOOPT;
+		if (!np->repflow)
+			return -ESRCH;
+		np->flow_label = 0;
+		np->repflow = 0;
+		return 0;
+	}
+
+	spin_lock_bh(&ip6_sk_fl_lock);
+	for (sflp = &np->ipv6_fl_list;
+	     (sfl = socklist_dereference(*sflp)) != NULL;
+	     sflp = &sfl->next) {
+		if (sfl->fl->label == freq->flr_label)
+			goto found;
+	}
+	spin_unlock_bh(&ip6_sk_fl_lock);
+	return -ESRCH;
+found:
+	if (freq->flr_label == (np->flow_label & IPV6_FLOWLABEL_MASK))
+		np->flow_label &= ~IPV6_FLOWLABEL_MASK;
+	*sflp = sfl->next;
+	spin_unlock_bh(&ip6_sk_fl_lock);
+	fl_release(sfl->fl);
+	kfree_rcu(sfl, rcu);
+	return 0;
+}
+
+static int ipv6_flowlabel_renew(struct sock *sk, struct in6_flowlabel_req *freq)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct net *net = sock_net(sk);
+	struct ipv6_fl_socklist *sfl;
+	int err;
+
+	rcu_read_lock_bh();
+	for_each_sk_fl_rcu(np, sfl) {
+		if (sfl->fl->label == freq->flr_label) {
+			err = fl6_renew(sfl->fl, freq->flr_linger,
+					freq->flr_expires);
+			rcu_read_unlock_bh();
+			return err;
+		}
+	}
+	rcu_read_unlock_bh();
+
+	if (freq->flr_share == IPV6_FL_S_NONE &&
+	    ns_capable(net->user_ns, CAP_NET_ADMIN)) {
+		struct ip6_flowlabel *fl = fl_lookup(net, freq->flr_label);
+
+		if (fl) {
+			err = fl6_renew(fl, freq->flr_linger,
+					freq->flr_expires);
+			fl_release(fl);
+			return err;
+		}
+	}
+	return -ESRCH;
+}
+
+static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq,
+		sockptr_t optval, int optlen)
+{
+	struct ipv6_fl_socklist *sfl, *sfl1 = NULL;
 	struct ip6_flowlabel *fl, *fl1 = NULL;
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct net *net = sock_net(sk);
+	int err;
 
+	if (freq->flr_flags & IPV6_FL_F_REFLECT) {
+		if (net->ipv6.sysctl.flowlabel_consistency) {
+			net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n");
+			return -EPERM;
+		}
 
-	if (optlen < sizeof(freq))
+		if (sk->sk_protocol != IPPROTO_TCP)
+			return -ENOPROTOOPT;
+		np->repflow = 1;
+		return 0;
+	}
+
+	if (freq->flr_label & ~IPV6_FLOWLABEL_MASK)
 		return -EINVAL;
+	if (net->ipv6.sysctl.flowlabel_state_ranges &&
+	    (freq->flr_label & IPV6_FLOWLABEL_STATELESS_FLAG))
+		return -ERANGE;
 
-	if (copy_from_user(&freq, optval, sizeof(freq)))
-		return -EFAULT;
+	fl = fl_create(net, sk, freq, optval, optlen, &err);
+	if (!fl)
+		return err;
 
-	switch (freq.flr_action) {
-	case IPV6_FL_A_PUT:
-		if (freq.flr_flags & IPV6_FL_F_REFLECT) {
-			if (sk->sk_protocol != IPPROTO_TCP)
-				return -ENOPROTOOPT;
-			if (!np->repflow)
-				return -ESRCH;
-			np->flow_label = 0;
-			np->repflow = 0;
-			return 0;
-		}
-		spin_lock_bh(&ip6_sk_fl_lock);
-		for (sflp = &np->ipv6_fl_list;
-		     (sfl = rcu_dereference_protected(*sflp,
-						      lockdep_is_held(&ip6_sk_fl_lock))) != NULL;
-		     sflp = &sfl->next) {
-			if (sfl->fl->label == freq.flr_label) {
-				if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
-					np->flow_label &= ~IPV6_FLOWLABEL_MASK;
-				*sflp = sfl->next;
-				spin_unlock_bh(&ip6_sk_fl_lock);
-				fl_release(sfl->fl);
-				kfree_rcu(sfl, rcu);
-				return 0;
-			}
-		}
-		spin_unlock_bh(&ip6_sk_fl_lock);
-		return -ESRCH;
+	sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
 
-	case IPV6_FL_A_RENEW:
+	if (freq->flr_label) {
+		err = -EEXIST;
 		rcu_read_lock_bh();
 		for_each_sk_fl_rcu(np, sfl) {
-			if (sfl->fl->label == freq.flr_label) {
-				err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
-				rcu_read_unlock_bh();
-				return err;
+			if (sfl->fl->label == freq->flr_label) {
+				if (freq->flr_flags & IPV6_FL_F_EXCL) {
+					rcu_read_unlock_bh();
+					goto done;
+				}
+				fl1 = sfl->fl;
+				if (!atomic_inc_not_zero(&fl1->users))
+					fl1 = NULL;
+				break;
 			}
 		}
 		rcu_read_unlock_bh();
 
-		if (freq.flr_share == IPV6_FL_S_NONE &&
-		    ns_capable(net->user_ns, CAP_NET_ADMIN)) {
-			fl = fl_lookup(net, freq.flr_label);
-			if (fl) {
-				err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
-				fl_release(fl);
-				return err;
-			}
-		}
-		return -ESRCH;
-
-	case IPV6_FL_A_GET:
-		if (freq.flr_flags & IPV6_FL_F_REFLECT) {
-			struct net *net = sock_net(sk);
-			if (net->ipv6.sysctl.flowlabel_consistency) {
-				net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n");
-				return -EPERM;
-			}
-
-			if (sk->sk_protocol != IPPROTO_TCP)
-				return -ENOPROTOOPT;
-
-			np->repflow = 1;
-			return 0;
-		}
-
-		if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
-			return -EINVAL;
-
-		if (net->ipv6.sysctl.flowlabel_state_ranges &&
-		    (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG))
-			return -ERANGE;
-
-		fl = fl_create(net, sk, &freq, optval, optlen, &err);
-		if (!fl)
-			return err;
-		sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
-
-		if (freq.flr_label) {
-			err = -EEXIST;
-			rcu_read_lock_bh();
-			for_each_sk_fl_rcu(np, sfl) {
-				if (sfl->fl->label == freq.flr_label) {
-					if (freq.flr_flags&IPV6_FL_F_EXCL) {
-						rcu_read_unlock_bh();
-						goto done;
-					}
-					fl1 = sfl->fl;
-					if (!atomic_inc_not_zero(&fl1->users))
-						fl1 = NULL;
-					break;
-				}
-			}
-			rcu_read_unlock_bh();
-
-			if (!fl1)
-				fl1 = fl_lookup(net, freq.flr_label);
-			if (fl1) {
+		if (!fl1)
+			fl1 = fl_lookup(net, freq->flr_label);
+		if (fl1) {
 recheck:
-				err = -EEXIST;
-				if (freq.flr_flags&IPV6_FL_F_EXCL)
-					goto release;
-				err = -EPERM;
-				if (fl1->share == IPV6_FL_S_EXCL ||
-				    fl1->share != fl->share ||
-				    ((fl1->share == IPV6_FL_S_PROCESS) &&
-				     (fl1->owner.pid != fl->owner.pid)) ||
-				    ((fl1->share == IPV6_FL_S_USER) &&
-				     !uid_eq(fl1->owner.uid, fl->owner.uid)))
-					goto release;
+			err = -EEXIST;
+			if (freq->flr_flags&IPV6_FL_F_EXCL)
+				goto release;
+			err = -EPERM;
+			if (fl1->share == IPV6_FL_S_EXCL ||
+			    fl1->share != fl->share ||
+			    ((fl1->share == IPV6_FL_S_PROCESS) &&
+			     (fl1->owner.pid != fl->owner.pid)) ||
+			    ((fl1->share == IPV6_FL_S_USER) &&
+			     !uid_eq(fl1->owner.uid, fl->owner.uid)))
+				goto release;
 
-				err = -ENOMEM;
-				if (!sfl1)
-					goto release;
-				if (fl->linger > fl1->linger)
-					fl1->linger = fl->linger;
-				if ((long)(fl->expires - fl1->expires) > 0)
-					fl1->expires = fl->expires;
-				fl_link(np, sfl1, fl1);
-				fl_free(fl);
-				return 0;
+			err = -ENOMEM;
+			if (!sfl1)
+				goto release;
+			if (fl->linger > fl1->linger)
+				fl1->linger = fl->linger;
+			if ((long)(fl->expires - fl1->expires) > 0)
+				fl1->expires = fl->expires;
+			fl_link(np, sfl1, fl1);
+			fl_free(fl);
+			return 0;
 
 release:
-				fl_release(fl1);
-				goto done;
-			}
+			fl_release(fl1);
+			goto done;
 		}
-		err = -ENOENT;
-		if (!(freq.flr_flags&IPV6_FL_F_CREATE))
-			goto done;
+	}
+	err = -ENOENT;
+	if (!(freq->flr_flags & IPV6_FL_F_CREATE))
+		goto done;
 
-		err = -ENOMEM;
-		if (!sfl1)
-			goto done;
+	err = -ENOMEM;
+	if (!sfl1)
+		goto done;
 
-		err = mem_check(sk);
-		if (err != 0)
-			goto done;
+	err = mem_check(sk);
+	if (err != 0)
+		goto done;
 
-		fl1 = fl_intern(net, fl, freq.flr_label);
-		if (fl1)
-			goto recheck;
+	fl1 = fl_intern(net, fl, freq->flr_label);
+	if (fl1)
+		goto recheck;
 
-		if (!freq.flr_label) {
-			if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
-					 &fl->label, sizeof(fl->label))) {
-				/* Intentionally ignore fault. */
-			}
+	if (!freq->flr_label) {
+		size_t offset = offsetof(struct in6_flowlabel_req, flr_label);
+
+		if (copy_to_sockptr_offset(optval, offset, &fl->label,
+				sizeof(fl->label))) {
+			/* Intentionally ignore fault. */
 		}
-
-		fl_link(np, sfl1, fl);
-		return 0;
-
-	default:
-		return -EINVAL;
 	}
 
+	fl_link(np, sfl1, fl);
+	return 0;
 done:
 	fl_free(fl);
 	kfree(sfl1);
 	return err;
+}
+
+int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen)
+{
+	struct in6_flowlabel_req freq;
+
+	if (optlen < sizeof(freq))
+		return -EINVAL;
+	if (copy_from_sockptr(&freq, optval, sizeof(freq)))
+		return -EFAULT;
+
+	switch (freq.flr_action) {
+	case IPV6_FL_A_PUT:
+		return ipv6_flowlabel_put(sk, &freq);
+	case IPV6_FL_A_RENEW:
+		return ipv6_flowlabel_renew(sk, &freq);
+	case IPV6_FL_A_GET:
+		return ipv6_flowlabel_get(sk, &freq, optval, optlen);
+	default:
+		return -EINVAL;
+	}
 }
 
 #ifdef CONFIG_PROC_FS
@@ -762,7 +805,7 @@
 {
 	struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 
-	state->pid_ns = proc_pid_ns(file_inode(seq->file));
+	state->pid_ns = proc_pid_ns(file_inode(seq->file)->i_sb);
 
 	rcu_read_lock_bh();
 	return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
@@ -858,6 +901,7 @@
 
 void ip6_flowlabel_cleanup(void)
 {
+	static_key_deferred_flush(&ipv6_flowlabel_exclusive);
 	del_timer(&ip6_fl_gc_timer);
 	unregister_pernet_subsys(&ip6_flowlabel_net_ops);
 }

--
Gitblit v1.6.2