Merge tag 'net-5.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "We have a few fixes for long standing issues, in particular Eric's fix
  to not underestimate the skb sizes, and my fix for brokenness of
  register_netdevice() error path. They may uncover other bugs so we
  will keep an eye on them. Also included are Willem's fixes for
  kmap(_atomic).

  Looking at the "current release" fixes, it seems we are about one rc
  behind a normal cycle. We've previously seen an uptick of "people had
  run their test suites" / "humans actually tried to use new features"
  fixes between rc2 and rc3.

  Summary:

  Current release - regressions:

   - fix feature enforcement to allow NETIF_F_HW_TLS_TX if IP_CSUM &&
     IPV6_CSUM

   - dcb: accept RTM_GETDCB messages carrying set-like DCB commands if
     user is admin for backward-compatibility

   - selftests/tls: fix selftests build after adding ChaCha20-Poly1305

  Current release - always broken:

   - ppp: fix refcount underflow on channel unbridge

   - bnxt_en: clear DEFRAG flag in firmware message when retry flashing

   - smc: fix out of bound access in the new netlink interface

  Previous releases - regressions:

   - fix use-after-free with UDP GRO by frags

   - mptcp: better msk-level shutdown

   - rndis_host: set proper input size for OID_GEN_PHYSICAL_MEDIUM
     request

   - i40e: xsk: fix potential NULL pointer dereferencing

  Previous releases - always broken:

   - skb frag: kmap_atomic fixes

   - avoid 32 x truesize under-estimation for tiny skbs

   - fix issues around register_netdevice() failures

   - udp: prevent reuseport_select_sock from reading uninitialized socks

   - dsa: unbind all switches from tree when DSA master unbinds

   - dsa: clear devlink port type before unregistering slave netdevs

   - can: isotp: isotp_getname(): fix kernel information leak

   - mlxsw: core: Thermal control fixes

   - ipv6: validate GSO SKB against MTU before finish IPv6 processing

   - stmmac: use __napi_schedule() for PREEMPT_RT

   - net: mvpp2: remove Pause and Asym_Pause support

  Misc:

   - remove from MAINTAINERS folks who had been inactive for >5yrs"

* tag 'net-5.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (58 commits)
  mptcp: fix locking in mptcp_disconnect()
  net: Allow NETIF_F_HW_TLS_TX if IP_CSUM && IPV6_CSUM
  MAINTAINERS: dccp: move Gerrit Renker to CREDITS
  MAINTAINERS: ipvs: move Wensong Zhang to CREDITS
  MAINTAINERS: tls: move Aviad to CREDITS
  MAINTAINERS: ena: remove Zorik Machulsky from reviewers
  MAINTAINERS: vrf: move Shrijeet to CREDITS
  MAINTAINERS: net: move Alexey Kuznetsov to CREDITS
  MAINTAINERS: altx: move Jay Cliburn to CREDITS
  net: avoid 32 x truesize under-estimation for tiny skbs
  nt: usb: USB_RTL8153_ECM should not default to y
  net: stmmac: fix taprio configuration when base_time is in the past
  net: stmmac: fix taprio schedule configuration
  net: tip: fix a couple kernel-doc markups
  net: sit: unregister_netdevice on newlink's error path
  net: stmmac: Fixed mtu channged by cache aligned
  cxgb4/chtls: Fix tid stuck due to wrong update of qid
  i40e: fix potential NULL pointer dereferencing
  net: stmmac: use __napi_schedule() for PREEMPT_RT
  can: mcp251xfd: mcp251xfd_handle_rxif_one(): fix wrong NULL pointer check
  ...

1 files changed, 24 insertions, 13 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 8fa739259041a..c360bb5367e24 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -9661,9 +9661,15 @@ static netdev_features_t netdev_fix_features(struct net_device *dev,
 		}
 	}
 
-	if ((features & NETIF_F_HW_TLS_TX) && !(features & NETIF_F_HW_CSUM)) {
-		netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n");
-		features &= ~NETIF_F_HW_TLS_TX;
+	if (features & NETIF_F_HW_TLS_TX) {
+		bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) ==
+			(NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM);
+		bool hw_csum = features & NETIF_F_HW_CSUM;
+
+		if (!ip_csum && !hw_csum) {
+			netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n");
+			features &= ~NETIF_F_HW_TLS_TX;
+		}
 	}
 
 	return features;
@@ -10077,17 +10083,11 @@ int register_netdevice(struct net_device *dev)
 	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
 	ret = notifier_to_errno(ret);
 	if (ret) {
+		/* Expect explicit free_netdev() on failure */
+		dev->needs_free_netdev = false;
 		rollback_registered(dev);
-		rcu_barrier();
-
-		dev->reg_state = NETREG_UNREGISTERED;
-		/* We should put the kobject that hold in
-		 * netdev_unregister_kobject(), otherwise
-		 * the net device cannot be freed when
-		 * driver calls free_netdev(), because the
-		 * kobject is being hold.
-		 */
-		kobject_put(&dev->dev.kobj);
+		net_set_todo(dev);
+		goto out;
 	}
 	/*
 	 *	Prevent userspace races by waiting until the network
@@ -10631,6 +10631,17 @@ void free_netdev(struct net_device *dev)
 	struct napi_struct *p, *n;
 
 	might_sleep();
+
+	/* When called immediately after register_netdevice() failed the unwind
+	 * handling may still be dismantling the device. Handle that case by
+	 * deferring the free.
+	 */
+	if (dev->reg_state == NETREG_UNREGISTERING) {
+		ASSERT_RTNL();
+		dev->needs_free_netdev = true;
+		return;
+	}
+
 	netif_free_tx_queues(dev);
 	netif_free_rx_queues(dev);