Merge tag 'net-6.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from wireless, bleutooth, BPF and netfilter.

  Current release - regressions:

   - core: drop bad gso csum_start and offset in virtio_net_hdr

   - wifi: mt76: fix null pointer access in mt792x_mac_link_bss_remove

   - eth: tun: add missing bpf_net_ctx_clear() in do_xdp_generic()

   - phy: aquantia: only poll GLOBAL_CFG regs on aqr113, aqr113c and
     aqr115c

  Current release - new code bugs:

   - smc: prevent UAF in inet_create()

   - bluetooth: btmtk: fix kernel crash when entering btmtk_usb_suspend

   - eth: bnxt: reject unsupported hash functions

  Previous releases - regressions:

   - sched: act_ct: take care of padding in struct zones_ht_key

   - netfilter: fix null-ptr-deref in iptable_nat_table_init().

   - tcp: adjust clamping window for applications specifying SO_RCVBUF

  Previous releases - always broken:

   - ethtool: rss: small fixes to spec and GET

   - mptcp:
      - fix signal endpoint re-add
      - pm: fix backup support in signal endpoints

   - wifi: ath12k: fix soft lockup on suspend

   - eth: bnxt_en: fix RSS logic in __bnxt_reserve_rings()

   - eth: ice: fix AF_XDP ZC timeout and concurrency issues

   - eth: mlx5:
      - fix missing lock on sync reset reload
      - fix error handling in irq_pool_request_irq"

* tag 'net-6.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (76 commits)
  mptcp: fix duplicate data handling
  mptcp: fix bad RCVPRUNED mib accounting
  ipv6: fix ndisc_is_useropt() handling for PIO
  igc: Fix double reset adapter triggered from a single taprio cmd
  net: MAINTAINERS: Demote Qualcomm IPA to "maintained"
  net: wan: fsl_qmc_hdlc: Discard received CRC
  net: wan: fsl_qmc_hdlc: Convert carrier_lock spinlock to a mutex
  net/mlx5e: Add a check for the return value from mlx5_port_set_eth_ptys
  net/mlx5e: Fix CT entry update leaks of modify header context
  net/mlx5e: Require mlx5 tc classifier action support for IPsec prio capability
  net/mlx5: Fix missing lock on sync reset reload
  net/mlx5: Lag, don't use the hardcoded value of the first port
  net/mlx5: DR, Fix 'stack guard page was hit' error in dr_rule
  net/mlx5: Fix error handling in irq_pool_request_irq
  net/mlx5: Always drain health in shutdown callback
  net: Add skbuff.h to MAINTAINERS
  r8169: don't increment tx_dropped in case of NETDEV_TX_BUSY
  netfilter: iptables: Fix potential null-ptr-deref in ip6table_nat_table_init().
  netfilter: iptables: Fix null-ptr-deref in iptable_nat_table_init().
  net: drop bad gso csum_start and offset in virtio_net_hdr
  ...

1 files changed, 22 insertions, 4 deletions

diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 39e2cbdf3801..a21c712350c3 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -100,6 +100,7 @@ static struct mptcp_sock *subflow_token_join_request(struct request_sock *req)
 		return NULL;
 	}
 	subflow_req->local_id = local_id;
+	subflow_req->request_bkup = mptcp_pm_is_backup(msk, (struct sock_common *)req);
 
 	return msk;
 }
@@ -168,6 +169,9 @@ static int subflow_check_req(struct request_sock *req,
 			return 0;
 	} else if (opt_mp_join) {
 		SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNRX);
+
+		if (mp_opt.backup)
+			SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNBACKUPRX);
 	}
 
 	if (opt_mp_capable && listener->request_mptcp) {
@@ -577,6 +581,9 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
 		subflow->mp_join = 1;
 		MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX);
 
+		if (subflow->backup)
+			MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKBACKUPRX);
+
 		if (subflow_use_different_dport(msk, sk)) {
 			pr_debug("synack inet_dport=%d %d",
 				 ntohs(inet_sk(sk)->inet_dport),
@@ -614,6 +621,8 @@ static int subflow_chk_local_id(struct sock *sk)
 		return err;
 
 	subflow_set_local_id(subflow, err);
+	subflow->request_bkup = mptcp_pm_is_backup(msk, (struct sock_common *)sk);
+
 	return 0;
 }
 
@@ -1221,14 +1230,22 @@ static void mptcp_subflow_discard_data(struct sock *ssk, struct sk_buff *skb,
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
 	bool fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN;
-	u32 incr;
+	struct tcp_sock *tp = tcp_sk(ssk);
+	u32 offset, incr, avail_len;
 
-	incr = limit >= skb->len ? skb->len + fin : limit;
+	offset = tp->copied_seq - TCP_SKB_CB(skb)->seq;
+	if (WARN_ON_ONCE(offset > skb->len))
+		goto out;
 
-	pr_debug("discarding=%d len=%d seq=%d", incr, skb->len,
-		 subflow->map_subflow_seq);
+	avail_len = skb->len - offset;
+	incr = limit >= avail_len ? avail_len + fin : limit;
+
+	pr_debug("discarding=%d len=%d offset=%d seq=%d", incr, skb->len,
+		 offset, subflow->map_subflow_seq);
 	MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DUPDATA);
 	tcp_sk(ssk)->copied_seq += incr;
+
+out:
 	if (!before(tcp_sk(ssk)->copied_seq, TCP_SKB_CB(skb)->end_seq))
 		sk_eat_skb(ssk, skb);
 	if (mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len)
@@ -2005,6 +2022,7 @@ static void subflow_ulp_clone(const struct request_sock *req,
 		new_ctx->fully_established = 1;
 		new_ctx->remote_key_valid = 1;
 		new_ctx->backup = subflow_req->backup;
+		new_ctx->request_bkup = subflow_req->request_bkup;
 		WRITE_ONCE(new_ctx->remote_id, subflow_req->remote_id);
 		new_ctx->token = subflow_req->token;
 		new_ctx->thmac = subflow_req->thmac;