Merge tag 'net-6.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from Bluetooth.

  Current release - regressions:

   - tcp: refine sk_rcvbuf increase for ooo packets

   - bluetooth: fix attempting to send HCI_Disconnect to BIS handle

   - rxrpc: fix over large frame size warning

   - eth: bcmgenet: initialize u64 stats seq counter

  Previous releases - regressions:

   - tcp: correct signedness in skb remaining space calculation

   - sched: abort __tc_modify_qdisc if parent class does not exist

   - vsock: fix transport_{g2h,h2g} TOCTOU

   - rxrpc: fix bug due to prealloc collision

   - tipc: fix use-after-free in tipc_conn_close().

   - bluetooth: fix not marking Broadcast Sink BIS as connected

   - phy: qca808x: fix WoL issue by utilizing at8031_set_wol()

   - eth: am65-cpsw-nuss: fix skb size by accounting for skb_shared_info

  Previous releases - always broken:

   - netlink: fix wraparounds of sk->sk_rmem_alloc.

   - atm: fix infinite recursive call of clip_push().

   - eth:
      - stmmac: fix interrupt handling for level-triggered mode in DWC_XGMAC2
      - rtsn: fix a null pointer dereference in rtsn_probe()"

* tag 'net-6.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (37 commits)
  net/sched: sch_qfq: Fix null-deref in agg_dequeue
  rxrpc: Fix oops due to non-existence of prealloc backlog struct
  rxrpc: Fix bug due to prealloc collision
  MAINTAINERS: remove myself as netronome maintainer
  selftests/net: packetdrill: add tcp_ooo-before-and-after-accept.pkt
  tcp: refine sk_rcvbuf increase for ooo packets
  net/sched: Abort __tc_modify_qdisc if parent class does not exist
  net: ethernet: ti: am65-cpsw-nuss: Fix skb size by accounting for skb_shared_info
  net: thunderx: avoid direct MTU assignment after WRITE_ONCE()
  selftests/tc-testing: Create test case for UAF scenario with DRR/NETEM/BLACKHOLE chain
  atm: clip: Fix NULL pointer dereference in vcc_sendmsg()
  atm: clip: Fix infinite recursive call of clip_push().
  atm: clip: Fix memory leak of struct clip_vcc.
  atm: clip: Fix potential null-ptr-deref in to_atmarpd().
  net: phy: smsc: Fix link failure in forced mode with Auto-MDIX
  net: phy: smsc: Force predictable MDI-X state on LAN87xx
  net: phy: smsc: Fix Auto-MDIX configuration when disabled by strap
  net: stmmac: Fix interrupt handling for level-triggered mode in DWC_XGMAC2
  rxrpc: Fix over large frame size warning
  net: airoha: Fix an error handling path in airoha_probe()
  ...

1 files changed, 48 insertions, 16 deletions

diff --git a/net/atm/clip.c b/net/atm/clip.c
index b234dc3bcb0d..f7a5565e794e 100644
--- a/net/atm/clip.c
+++ b/net/atm/clip.c
@@ -45,7 +45,8 @@
 #include <net/atmclip.h>
 
 static struct net_device *clip_devs;
-static struct atm_vcc *atmarpd;
+static struct atm_vcc __rcu *atmarpd;
+static DEFINE_MUTEX(atmarpd_lock);
 static struct timer_list idle_timer;
 static const struct neigh_ops clip_neigh_ops;
 
@@ -53,24 +54,35 @@ static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
 {
 	struct sock *sk;
 	struct atmarp_ctrl *ctrl;
+	struct atm_vcc *vcc;
 	struct sk_buff *skb;
+	int err = 0;
 
 	pr_debug("(%d)\n", type);
-	if (!atmarpd)
-		return -EUNATCH;
+
+	rcu_read_lock();
+	vcc = rcu_dereference(atmarpd);
+	if (!vcc) {
+		err = -EUNATCH;
+		goto unlock;
+	}
 	skb = alloc_skb(sizeof(struct atmarp_ctrl), GFP_ATOMIC);
-	if (!skb)
-		return -ENOMEM;
+	if (!skb) {
+		err = -ENOMEM;
+		goto unlock;
+	}
 	ctrl = skb_put(skb, sizeof(struct atmarp_ctrl));
 	ctrl->type = type;
 	ctrl->itf_num = itf;
 	ctrl->ip = ip;
-	atm_force_charge(atmarpd, skb->truesize);
+	atm_force_charge(vcc, skb->truesize);
 
-	sk = sk_atm(atmarpd);
+	sk = sk_atm(vcc);
 	skb_queue_tail(&sk->sk_receive_queue, skb);
 	sk->sk_data_ready(sk);
-	return 0;
+unlock:
+	rcu_read_unlock();
+	return err;
 }
 
 static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
@@ -417,6 +429,8 @@ static int clip_mkip(struct atm_vcc *vcc, int timeout)
 
 	if (!vcc->push)
 		return -EBADFD;
+	if (vcc->user_back)
+		return -EINVAL;
 	clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
 	if (!clip_vcc)
 		return -ENOMEM;
@@ -607,17 +621,27 @@ static void atmarpd_close(struct atm_vcc *vcc)
 {
 	pr_debug("\n");
 
-	rtnl_lock();
-	atmarpd = NULL;
+	mutex_lock(&atmarpd_lock);
+	RCU_INIT_POINTER(atmarpd, NULL);
+	mutex_unlock(&atmarpd_lock);
+
+	synchronize_rcu();
 	skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
-	rtnl_unlock();
 
 	pr_debug("(done)\n");
 	module_put(THIS_MODULE);
 }
 
+static int atmarpd_send(struct atm_vcc *vcc, struct sk_buff *skb)
+{
+	atm_return_tx(vcc, skb);
+	dev_kfree_skb_any(skb);
+	return 0;
+}
+
 static const struct atmdev_ops atmarpd_dev_ops = {
-	.close = atmarpd_close
+	.close = atmarpd_close,
+	.send = atmarpd_send
 };
 
 
@@ -631,15 +655,18 @@ static struct atm_dev atmarpd_dev = {
 
 static int atm_init_atmarp(struct atm_vcc *vcc)
 {
-	rtnl_lock();
+	if (vcc->push == clip_push)
+		return -EINVAL;
+
+	mutex_lock(&atmarpd_lock);
 	if (atmarpd) {
-		rtnl_unlock();
+		mutex_unlock(&atmarpd_lock);
 		return -EADDRINUSE;
 	}
 
 	mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
 
-	atmarpd = vcc;
+	rcu_assign_pointer(atmarpd, vcc);
 	set_bit(ATM_VF_META, &vcc->flags);
 	set_bit(ATM_VF_READY, &vcc->flags);
 	    /* allow replies and avoid getting closed if signaling dies */
@@ -648,13 +675,14 @@ static int atm_init_atmarp(struct atm_vcc *vcc)
 	vcc->push = NULL;
 	vcc->pop = NULL; /* crash */
 	vcc->push_oam = NULL; /* crash */
-	rtnl_unlock();
+	mutex_unlock(&atmarpd_lock);
 	return 0;
 }
 
 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 {
 	struct atm_vcc *vcc = ATM_SD(sock);
+	struct sock *sk = sock->sk;
 	int err = 0;
 
 	switch (cmd) {
@@ -675,14 +703,18 @@ static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 		err = clip_create(arg);
 		break;
 	case ATMARPD_CTRL:
+		lock_sock(sk);
 		err = atm_init_atmarp(vcc);
 		if (!err) {
 			sock->state = SS_CONNECTED;
 			__module_get(THIS_MODULE);
 		}
+		release_sock(sk);
 		break;
 	case ATMARP_MKIP:
+		lock_sock(sk);
 		err = clip_mkip(vcc, arg);
+		release_sock(sk);
 		break;
 	case ATMARP_SETENTRY:
 		err = clip_setentry(vcc, (__force __be32)arg);