Merge tag 'net-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Large effort by Eric to lower rtnl_lock pressure and remove locks:

      - Make commonly used parts of rtnetlink (address, route dumps
        etc) lockless, protected by RCU instead of rtnl_lock.

      - Add a netns exit callback which already holds rtnl_lock,
        allowing netns exit to take rtnl_lock once in the core instead
        of once for each driver / callback.

      - Remove locks / serialization in the socket diag interface.

      - Remove 6 calls to synchronize_rcu() while holding rtnl_lock.

      - Remove the dev_base_lock, depend on RCU where necessary.

   - Support busy polling on a per-epoll context basis. Poll length and
     budget parameters can be set independently of system defaults.

   - Introduce struct net_hotdata, to make sure read-mostly global
     config variables fit in as few cache lines as possible.

   - Add optional per-nexthop statistics to ease monitoring / debug of
     ECMP imbalance problems.

   - Support TCP_NOTSENT_LOWAT in MPTCP.

   - Ensure that IPv6 temporary addresses' preferred lifetimes are long
     enough, compared to other configured lifetimes, and at least 2 sec.

   - Support forwarding of ICMP Error messages in IPSec, per RFC 4301.

   - Add support for the independent control state machine for bonding
     per IEEE 802.1AX-2008 5.4.15 in addition to the existing coupled
     control state machine.

   - Add "network ID" to MCTP socket APIs to support hosts with multiple
     disjoint MCTP networks.

   - Re-use the mono_delivery_time skbuff bit for packets which user
     space wants to be sent at a specified time. Maintain the timing
     information while traversing veth links, bridge etc.

   - Take advantage of MSG_SPLICE_PAGES for RxRPC DATA and ACK packets.

   - Simplify many places iterating over netdevs by using an xarray
     instead of a hash table walk (hash table remains in place, for use
     on fastpaths).

   - Speed up scanning for expired routes by keeping a dedicated list.

   - Speed up "generic" XDP by trying harder to avoid large allocations.

   - Support attaching arbitrary metadata to netconsole messages.

  Things we sprinkled into general kernel code:

   - Enforce VM_IOREMAP flag and range in ioremap_page_range and
     introduce VM_SPARSE kind and vm_area_[un]map_pages (used by
     bpf_arena).

   - Rework selftest harness to enable the use of the full range of ksft
     exit code (pass, fail, skip, xfail, xpass).

  Netfilter:

   - Allow userspace to define a table that is exclusively owned by a
     daemon (via netlink socket aliveness) without auto-removing this
     table when the userspace program exits. Such table gets marked as
     orphaned and a restarting management daemon can re-attach/regain
     ownership.

   - Speed up element insertions to nftables' concatenated-ranges set
     type. Compact a few related data structures.

  BPF:

   - Add BPF token support for delegating a subset of BPF subsystem
     functionality from privileged system-wide daemons such as systemd
     through special mount options for userns-bound BPF fs to a trusted
     & unprivileged application.

   - Introduce bpf_arena which is sparse shared memory region between
     BPF program and user space where structures inside the arena can
     have pointers to other areas of the arena, and pointers work
     seamlessly for both user-space programs and BPF programs.

   - Introduce may_goto instruction that is a contract between the
     verifier and the program. The verifier allows the program to loop
     assuming it's behaving well, but reserves the right to terminate
     it.

   - Extend the BPF verifier to enable static subprog calls in spin lock
     critical sections.

   - Support registration of struct_ops types from modules which helps
     projects like fuse-bpf that seeks to implement a new struct_ops
     type.

   - Add support for retrieval of cookies for perf/kprobe multi links.

   - Support arbitrary TCP SYN cookie generation / validation in the TC
     layer with BPF to allow creating SYN flood handling in BPF
     firewalls.

   - Add code generation to inline the bpf_kptr_xchg() helper which
     improves performance when stashing/popping the allocated BPF
     objects.

  Wireless:

   - Add SPP (signaling and payload protected) AMSDU support.

   - Support wider bandwidth OFDMA, as required for EHT operation.

  Driver API:

   - Major overhaul of the Energy Efficient Ethernet internals to
     support new link modes (2.5GE, 5GE), share more code between
     drivers (especially those using phylib), and encourage more
     uniform behavior. Convert and clean up drivers.

   - Define an API for querying per netdev queue statistics from
     drivers.

   - IPSec: account in global stats for fully offloaded sessions.

   - Create a concept of Ethernet PHY Packages at the Device Tree level,
     to allow parameterizing the existing PHY package code.

   - Enable Rx hashing (RSS) on GTP protocol fields.

  Misc:

   - Improvements and refactoring all over networking selftests.

   - Create uniform module aliases for TC classifiers, actions, and
     packet schedulers to simplify creating modprobe policies.

   - Address all missing MODULE_DESCRIPTION() warnings in networking.

   - Extend the Netlink descriptions in YAML to cover message
     encapsulation or "Netlink polymorphism", where interpretation of
     nested attributes depends on link type, classifier type or some
     other "class type".

  Drivers:

   - Ethernet high-speed NICs:
      - Add a new driver for Marvell's Octeon PCI Endpoint NIC VF.
      - Intel (100G, ice, idpf):
         - support E825-C devices
      - nVidia/Mellanox:
         - support devices with one port and multiple PCIe links
      - Broadcom (bnxt):
         - support n-tuple filters
         - support configuring the RSS key
      - Wangxun (ngbe/txgbe):
         - implement irq_domain for TXGBE's sub-interrupts
      - Pensando/AMD:
         - support XDP
         - optimize queue submission and wakeup handling (+17% bps)
         - optimize struct layout, saving 28% of memory on queues

   - Ethernet NICs embedded and virtual:
      - Google cloud vNIC:
         - refactor driver to perform memory allocations for new queue
           config before stopping and freeing the old queue memory
      - Synopsys (stmmac):
         - obey queueMaxSDU and implement counters required by 802.1Qbv
      - Renesas (ravb):
         - support packet checksum offload
         - suspend to RAM and runtime PM support

   - Ethernet switches:
      - nVidia/Mellanox:
         - support for nexthop group statistics
      - Microchip:
         - ksz8: implement PHY loopback
         - add support for KSZ8567, a 7-port 10/100Mbps switch

   - PTP:
      - New driver for RENESAS FemtoClock3 Wireless clock generator.
      - Support OCP PTP cards designed and built by Adva.

   - CAN:
      - Support recvmsg() flags for own, local and remote traffic on CAN
        BCM sockets.
      - Support for esd GmbH PCIe/402 CAN device family.
      - m_can:
         - Rx/Tx submission coalescing
         - wake on frame Rx

   - WiFi:
      - Intel (iwlwifi):
         - enable signaling and payload protected A-MSDUs
         - support wider-bandwidth OFDMA
         - support for new devices
         - bump FW API to 89 for AX devices; 90 for BZ/SC devices
      - MediaTek (mt76):
         - mt7915: newer ADIE version support
         - mt7925: radio temperature sensor support
      - Qualcomm (ath11k):
         - support 6 GHz station power modes: Low Power Indoor (LPI),
           Standard Power) SP and Very Low Power (VLP)
         - QCA6390 & WCN6855: support 2 concurrent station interfaces
         - QCA2066 support
      - Qualcomm (ath12k):
         - refactoring in preparation for Multi-Link Operation (MLO)
           support
         - 1024 Block Ack window size support
         - firmware-2.bin support
         - support having multiple identical PCI devices (firmware needs
           to have ATH12K_FW_FEATURE_MULTI_QRTR_ID)
         - QCN9274: support split-PHY devices
         - WCN7850: enable Power Save Mode in station mode
         - WCN7850: P2P support
      - RealTek:
         - rtw88: support for more rtw8811cu and rtw8821cu devices
         - rtw89: support SCAN_RANDOM_SN and SET_SCAN_DWELL
         - rtlwifi: speed up USB firmware initialization
         - rtwl8xxxu:
             - RTL8188F: concurrent interface support
             - Channel Switch Announcement (CSA) support in AP mode
      - Broadcom (brcmfmac):
         - per-vendor feature support
         - per-vendor SAE password setup
         - DMI nvram filename quirk for ACEPC W5 Pro"

* tag 'net-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2255 commits)
  nexthop: Fix splat with CONFIG_DEBUG_PREEMPT=y
  nexthop: Fix out-of-bounds access during attribute validation
  nexthop: Only parse NHA_OP_FLAGS for dump messages that require it
  nexthop: Only parse NHA_OP_FLAGS for get messages that require it
  bpf: move sleepable flag from bpf_prog_aux to bpf_prog
  bpf: hardcode BPF_PROG_PACK_SIZE to 2MB * num_possible_nodes()
  selftests/bpf: Add kprobe multi triggering benchmarks
  ptp: Move from simple ida to xarray
  vxlan: Remove generic .ndo_get_stats64
  vxlan: Do not alloc tstats manually
  devlink: Add comments to use netlink gen tool
  nfp: flower: handle acti_netdevs allocation failure
  net/packet: Add getsockopt support for PACKET_COPY_THRESH
  net/netlink: Add getsockopt support for NETLINK_LISTEN_ALL_NSID
  selftests/bpf: Add bpf_arena_htab test.
  selftests/bpf: Add bpf_arena_list test.
  selftests/bpf: Add unit tests for bpf_arena_alloc/free_pages
  bpf: Add helper macro bpf_addr_space_cast()
  libbpf: Recognize __arena global variables.
  bpftool: Recognize arena map type
  ...

1 files changed, 125 insertions, 75 deletions

diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index 2a81880dac7b7..fa39b62652385 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -81,12 +81,80 @@
 #include <net/scm.h>
 #include <net/tcp_states.h>
 
-#include "scm.h"
+struct unix_sock *unix_get_socket(struct file *filp)
+{
+	struct inode *inode = file_inode(filp);
+
+	/* Socket ? */
+	if (S_ISSOCK(inode->i_mode) && !(filp->f_mode & FMODE_PATH)) {
+		struct socket *sock = SOCKET_I(inode);
+		const struct proto_ops *ops;
+		struct sock *sk = sock->sk;
+
+		ops = READ_ONCE(sock->ops);
 
-/* Internal data structures and random procedures: */
+		/* PF_UNIX ? */
+		if (sk && ops && ops->family == PF_UNIX)
+			return unix_sk(sk);
+	}
+
+	return NULL;
+}
 
+DEFINE_SPINLOCK(unix_gc_lock);
+unsigned int unix_tot_inflight;
 static LIST_HEAD(gc_candidates);
-static DECLARE_WAIT_QUEUE_HEAD(unix_gc_wait);
+static LIST_HEAD(gc_inflight_list);
+
+/* Keep the number of times in flight count for the file
+ * descriptor if it is for an AF_UNIX socket.
+ */
+void unix_inflight(struct user_struct *user, struct file *filp)
+{
+	struct unix_sock *u = unix_get_socket(filp);
+
+	spin_lock(&unix_gc_lock);
+
+	if (u) {
+		if (!u->inflight) {
+			WARN_ON_ONCE(!list_empty(&u->link));
+			list_add_tail(&u->link, &gc_inflight_list);
+		} else {
+			WARN_ON_ONCE(list_empty(&u->link));
+		}
+		u->inflight++;
+
+		/* Paired with READ_ONCE() in wait_for_unix_gc() */
+		WRITE_ONCE(unix_tot_inflight, unix_tot_inflight + 1);
+	}
+
+	WRITE_ONCE(user->unix_inflight, user->unix_inflight + 1);
+
+	spin_unlock(&unix_gc_lock);
+}
+
+void unix_notinflight(struct user_struct *user, struct file *filp)
+{
+	struct unix_sock *u = unix_get_socket(filp);
+
+	spin_lock(&unix_gc_lock);
+
+	if (u) {
+		WARN_ON_ONCE(!u->inflight);
+		WARN_ON_ONCE(list_empty(&u->link));
+
+		u->inflight--;
+		if (!u->inflight)
+			list_del_init(&u->link);
+
+		/* Paired with READ_ONCE() in wait_for_unix_gc() */
+		WRITE_ONCE(unix_tot_inflight, unix_tot_inflight - 1);
+	}
+
+	WRITE_ONCE(user->unix_inflight, user->unix_inflight - 1);
+
+	spin_unlock(&unix_gc_lock);
+}
 
 static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
 			  struct sk_buff_head *hitlist)
@@ -105,20 +173,15 @@ static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
 
 			while (nfd--) {
 				/* Get the socket the fd matches if it indeed does so */
-				struct sock *sk = unix_get_socket(*fp++);
-
-				if (sk) {
-					struct unix_sock *u = unix_sk(sk);
+				struct unix_sock *u = unix_get_socket(*fp++);
 
-					/* Ignore non-candidates, they could
-					 * have been added to the queues after
-					 * starting the garbage collection
-					 */
-					if (test_bit(UNIX_GC_CANDIDATE, &u->gc_flags)) {
-						hit = true;
+				/* Ignore non-candidates, they could have been added
+				 * to the queues after starting the garbage collection
+				 */
+				if (u && test_bit(UNIX_GC_CANDIDATE, &u->gc_flags)) {
+					hit = true;
 
-						func(u);
-					}
+					func(u);
 				}
 			}
 			if (hit && hitlist != NULL) {
@@ -151,7 +214,7 @@ static void scan_children(struct sock *x, void (*func)(struct unix_sock *),
 			/* An embryo cannot be in-flight, so it's safe
 			 * to use the list link.
 			 */
-			BUG_ON(!list_empty(&u->link));
+			WARN_ON_ONCE(!list_empty(&u->link));
 			list_add_tail(&u->link, &embryos);
 		}
 		spin_unlock(&x->sk_receive_queue.lock);
@@ -166,17 +229,18 @@ static void scan_children(struct sock *x, void (*func)(struct unix_sock *),
 
 static void dec_inflight(struct unix_sock *usk)
 {
-	atomic_long_dec(&usk->inflight);
+	usk->inflight--;
 }
 
 static void inc_inflight(struct unix_sock *usk)
 {
-	atomic_long_inc(&usk->inflight);
+	usk->inflight++;
 }
 
 static void inc_inflight_move_tail(struct unix_sock *u)
 {
-	atomic_long_inc(&u->inflight);
+	u->inflight++;
+
 	/* If this still might be part of a cycle, move it to the end
 	 * of the list, so that it's checked even if it was already
 	 * passed over
@@ -186,40 +250,16 @@ static void inc_inflight_move_tail(struct unix_sock *u)
 }
 
 static bool gc_in_progress;
-#define UNIX_INFLIGHT_TRIGGER_GC 16000
-
-void wait_for_unix_gc(void)
-{
-	/* If number of inflight sockets is insane,
-	 * force a garbage collect right now.
-	 * Paired with the WRITE_ONCE() in unix_inflight(),
-	 * unix_notinflight() and gc_in_progress().
-	 */
-	if (READ_ONCE(unix_tot_inflight) > UNIX_INFLIGHT_TRIGGER_GC &&
-	    !READ_ONCE(gc_in_progress))
-		unix_gc();
-	wait_event(unix_gc_wait, gc_in_progress == false);
-}
 
-/* The external entry point: unix_gc() */
-void unix_gc(void)
+static void __unix_gc(struct work_struct *work)
 {
-	struct sk_buff *next_skb, *skb;
-	struct unix_sock *u;
-	struct unix_sock *next;
 	struct sk_buff_head hitlist;
-	struct list_head cursor;
+	struct unix_sock *u, *next;
 	LIST_HEAD(not_cycle_list);
+	struct list_head cursor;
 
 	spin_lock(&unix_gc_lock);
 
-	/* Avoid a recursive GC. */
-	if (gc_in_progress)
-		goto out;
-
-	/* Paired with READ_ONCE() in wait_for_unix_gc(). */
-	WRITE_ONCE(gc_in_progress, true);
-
 	/* First, select candidates for garbage collection.  Only
 	 * in-flight sockets are considered, and from those only ones
 	 * which don't have any external reference.
@@ -237,14 +277,12 @@ void unix_gc(void)
 	 */
 	list_for_each_entry_safe(u, next, &gc_inflight_list, link) {
 		long total_refs;
-		long inflight_refs;
 
 		total_refs = file_count(u->sk.sk_socket->file);
-		inflight_refs = atomic_long_read(&u->inflight);
 
-		BUG_ON(inflight_refs < 1);
-		BUG_ON(total_refs < inflight_refs);
-		if (total_refs == inflight_refs) {
+		WARN_ON_ONCE(!u->inflight);
+		WARN_ON_ONCE(total_refs < u->inflight);
+		if (total_refs == u->inflight) {
 			list_move_tail(&u->link, &gc_candidates);
 			__set_bit(UNIX_GC_CANDIDATE, &u->gc_flags);
 			__set_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags);
@@ -271,7 +309,7 @@ void unix_gc(void)
 		/* Move cursor to after the current position. */
 		list_move(&cursor, &u->link);
 
-		if (atomic_long_read(&u->inflight) > 0) {
+		if (u->inflight) {
 			list_move_tail(&u->link, &not_cycle_list);
 			__clear_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags);
 			scan_children(&u->sk, inc_inflight_move_tail, NULL);
@@ -306,38 +344,50 @@ void unix_gc(void)
 
 	spin_unlock(&unix_gc_lock);
 
-	/* We need io_uring to clean its registered files, ignore all io_uring
-	 * originated skbs. It's fine as io_uring doesn't keep references to
-	 * other io_uring instances and so killing all other files in the cycle
-	 * will put all io_uring references forcing it to go through normal
-	 * release.path eventually putting registered files.
-	 */
-	skb_queue_walk_safe(&hitlist, skb, next_skb) {
-		if (skb->destructor == io_uring_destruct_scm) {
-			__skb_unlink(skb, &hitlist);
-			skb_queue_tail(&skb->sk->sk_receive_queue, skb);
-		}
-	}
-
 	/* Here we are. Hitlist is filled. Die. */
 	__skb_queue_purge(&hitlist);
 
 	spin_lock(&unix_gc_lock);
 
-	/* There could be io_uring registered files, just push them back to
-	 * the inflight list
-	 */
-	list_for_each_entry_safe(u, next, &gc_candidates, link)
-		list_move_tail(&u->link, &gc_inflight_list);
-
 	/* All candidates should have been detached by now. */
-	BUG_ON(!list_empty(&gc_candidates));
+	WARN_ON_ONCE(!list_empty(&gc_candidates));
 
 	/* Paired with READ_ONCE() in wait_for_unix_gc(). */
 	WRITE_ONCE(gc_in_progress, false);
 
-	wake_up(&unix_gc_wait);
-
- out:
 	spin_unlock(&unix_gc_lock);
 }
+
+static DECLARE_WORK(unix_gc_work, __unix_gc);
+
+void unix_gc(void)
+{
+	WRITE_ONCE(gc_in_progress, true);
+	queue_work(system_unbound_wq, &unix_gc_work);
+}
+
+#define UNIX_INFLIGHT_TRIGGER_GC 16000
+#define UNIX_INFLIGHT_SANE_USER (SCM_MAX_FD * 8)
+
+void wait_for_unix_gc(struct scm_fp_list *fpl)
+{
+	/* If number of inflight sockets is insane,
+	 * force a garbage collect right now.
+	 *
+	 * Paired with the WRITE_ONCE() in unix_inflight(),
+	 * unix_notinflight(), and __unix_gc().
+	 */
+	if (READ_ONCE(unix_tot_inflight) > UNIX_INFLIGHT_TRIGGER_GC &&
+	    !READ_ONCE(gc_in_progress))
+		unix_gc();
+
+	/* Penalise users who want to send AF_UNIX sockets
+	 * but whose sockets have not been received yet.
+	 */
+	if (!fpl || !fpl->count_unix ||
+	    READ_ONCE(fpl->user->unix_inflight) < UNIX_INFLIGHT_SANE_USER)
+		return;
+
+	if (READ_ONCE(gc_in_progress))
+		flush_work(&unix_gc_work);
+}