diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /net/unix/garbage.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to '')
-rw-r--r-- | net/unix/garbage.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/net/unix/garbage.c b/net/unix/garbage.c new file mode 100644 index 000000000..dc2763540 --- /dev/null +++ b/net/unix/garbage.c @@ -0,0 +1,335 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * NET3: Garbage Collector For AF_UNIX sockets + * + * Garbage Collector: + * Copyright (C) Barak A. Pearlmutter. + * + * Chopped about by Alan Cox 22/3/96 to make it fit the AF_UNIX socket problem. + * If it doesn't work blame me, it worked when Barak sent it. + * + * Assumptions: + * + * - object w/ a bit + * - free list + * + * Current optimizations: + * + * - explicit stack instead of recursion + * - tail recurse on first born instead of immediate push/pop + * - we gather the stuff that should not be killed into tree + * and stack is just a path from root to the current pointer. + * + * Future optimizations: + * + * - don't just push entire root set; process in place + * + * Fixes: + * Alan Cox 07 Sept 1997 Vmalloc internal stack as needed. + * Cope with changing max_files. + * Al Viro 11 Oct 1998 + * Graph may have cycles. That is, we can send the descriptor + * of foo to bar and vice versa. Current code chokes on that. + * Fix: move SCM_RIGHTS ones into the separate list and then + * skb_free() them all instead of doing explicit fput's. + * Another problem: since fput() may block somebody may + * create a new unix_socket when we are in the middle of sweep + * phase. Fix: revert the logic wrt MARKED. Mark everything + * upon the beginning and unmark non-junk ones. + * + * [12 Oct 1998] AAARGH! New code purges all SCM_RIGHTS + * sent to connect()'ed but still not accept()'ed sockets. + * Fixed. Old code had slightly different problem here: + * extra fput() in situation when we passed the descriptor via + * such socket and closed it (descriptor). That would happen on + * each unix_gc() until the accept(). Since the struct file in + * question would go to the free list and might be reused... + * That might be the reason of random oopses on filp_close() + * in unrelated processes. + * + * AV 28 Feb 1999 + * Kill the explicit allocation of stack. Now we keep the tree + * with root in dummy + pointer (gc_current) to one of the nodes. + * Stack is represented as path from gc_current to dummy. Unmark + * now means "add to tree". Push == "make it a son of gc_current". + * Pop == "move gc_current to parent". We keep only pointers to + * parents (->gc_tree). + * AV 1 Mar 1999 + * Damn. Added missing check for ->dead in listen queues scanning. + * + * Miklos Szeredi 25 Jun 2007 + * Reimplement with a cycle collecting algorithm. This should + * solve several problems with the previous code, like being racy + * wrt receive and holding up unrelated socket operations. + */ + +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/socket.h> +#include <linux/un.h> +#include <linux/net.h> +#include <linux/fs.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/file.h> +#include <linux/proc_fs.h> +#include <linux/mutex.h> +#include <linux/wait.h> + +#include <net/sock.h> +#include <net/af_unix.h> +#include <net/scm.h> +#include <net/tcp_states.h> + +#include "scm.h" + +/* Internal data structures and random procedures: */ + +static LIST_HEAD(gc_candidates); +static DECLARE_WAIT_QUEUE_HEAD(unix_gc_wait); + +static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *), + struct sk_buff_head *hitlist) +{ + struct sk_buff *skb; + struct sk_buff *next; + + spin_lock(&x->sk_receive_queue.lock); + skb_queue_walk_safe(&x->sk_receive_queue, skb, next) { + /* Do we have file descriptors ? */ + if (UNIXCB(skb).fp) { + bool hit = false; + /* Process the descriptors of this socket */ + int nfd = UNIXCB(skb).fp->count; + struct file **fp = UNIXCB(skb).fp->fp; + + 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); + + /* 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; + + func(u); + } + } + } + if (hit && hitlist != NULL) { + __skb_unlink(skb, &x->sk_receive_queue); + __skb_queue_tail(hitlist, skb); + } + } + } + spin_unlock(&x->sk_receive_queue.lock); +} + +static void scan_children(struct sock *x, void (*func)(struct unix_sock *), + struct sk_buff_head *hitlist) +{ + if (x->sk_state != TCP_LISTEN) { + scan_inflight(x, func, hitlist); + } else { + struct sk_buff *skb; + struct sk_buff *next; + struct unix_sock *u; + LIST_HEAD(embryos); + + /* For a listening socket collect the queued embryos + * and perform a scan on them as well. + */ + spin_lock(&x->sk_receive_queue.lock); + skb_queue_walk_safe(&x->sk_receive_queue, skb, next) { + u = unix_sk(skb->sk); + + /* An embryo cannot be in-flight, so it's safe + * to use the list link. + */ + BUG_ON(!list_empty(&u->link)); + list_add_tail(&u->link, &embryos); + } + spin_unlock(&x->sk_receive_queue.lock); + + while (!list_empty(&embryos)) { + u = list_entry(embryos.next, struct unix_sock, link); + scan_inflight(&u->sk, func, hitlist); + list_del_init(&u->link); + } + } +} + +static void dec_inflight(struct unix_sock *usk) +{ + atomic_long_dec(&usk->inflight); +} + +static void inc_inflight(struct unix_sock *usk) +{ + atomic_long_inc(&usk->inflight); +} + +static void inc_inflight_move_tail(struct unix_sock *u) +{ + atomic_long_inc(&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 + */ + if (test_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags)) + list_move_tail(&u->link, &gc_candidates); +} + +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) +{ + struct sk_buff *next_skb, *skb; + struct unix_sock *u; + struct unix_sock *next; + struct sk_buff_head hitlist; + struct list_head cursor; + LIST_HEAD(not_cycle_list); + + 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. + * + * Holding unix_gc_lock will protect these candidates from + * being detached, and hence from gaining an external + * reference. Since there are no possible receivers, all + * buffers currently on the candidates' queues stay there + * during the garbage collection. + * + * We also know that no new candidate can be added onto the + * receive queues. Other, non candidate sockets _can_ be + * added to queue, so we must make sure only to touch + * candidates. + */ + 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) { + list_move_tail(&u->link, &gc_candidates); + __set_bit(UNIX_GC_CANDIDATE, &u->gc_flags); + __set_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags); + } + } + + /* Now remove all internal in-flight reference to children of + * the candidates. + */ + list_for_each_entry(u, &gc_candidates, link) + scan_children(&u->sk, dec_inflight, NULL); + + /* Restore the references for children of all candidates, + * which have remaining references. Do this recursively, so + * only those remain, which form cyclic references. + * + * Use a "cursor" link, to make the list traversal safe, even + * though elements might be moved about. + */ + list_add(&cursor, &gc_candidates); + while (cursor.next != &gc_candidates) { + u = list_entry(cursor.next, struct unix_sock, link); + + /* Move cursor to after the current position. */ + list_move(&cursor, &u->link); + + if (atomic_long_read(&u->inflight) > 0) { + list_move_tail(&u->link, ¬_cycle_list); + __clear_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags); + scan_children(&u->sk, inc_inflight_move_tail, NULL); + } + } + list_del(&cursor); + + /* Now gc_candidates contains only garbage. Restore original + * inflight counters for these as well, and remove the skbuffs + * which are creating the cycle(s). + */ + skb_queue_head_init(&hitlist); + list_for_each_entry(u, &gc_candidates, link) + scan_children(&u->sk, inc_inflight, &hitlist); + + /* not_cycle_list contains those sockets which do not make up a + * cycle. Restore these to the inflight list. + */ + while (!list_empty(¬_cycle_list)) { + u = list_entry(not_cycle_list.next, struct unix_sock, link); + __clear_bit(UNIX_GC_CANDIDATE, &u->gc_flags); + list_move_tail(&u->link, &gc_inflight_list); + } + + 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->scm_io_uring) { + __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)); + + /* 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); +} |