From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- kernel/user.c | 252 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 252 insertions(+) create mode 100644 kernel/user.c (limited to 'kernel/user.c') diff --git a/kernel/user.c b/kernel/user.c new file mode 100644 index 000000000..d667debea --- /dev/null +++ b/kernel/user.c @@ -0,0 +1,252 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * The "user cache". + * + * (C) Copyright 1991-2000 Linus Torvalds + * + * We have a per-user structure to keep track of how many + * processes, files etc the user has claimed, in order to be + * able to have per-user limits for system resources. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * userns count is 1 for root user, 1 for init_uts_ns, + * and 1 for... ? + */ +struct user_namespace init_user_ns = { + .uid_map = { + .nr_extents = 1, + { + .extent[0] = { + .first = 0, + .lower_first = 0, + .count = 4294967295U, + }, + }, + }, + .gid_map = { + .nr_extents = 1, + { + .extent[0] = { + .first = 0, + .lower_first = 0, + .count = 4294967295U, + }, + }, + }, + .projid_map = { + .nr_extents = 1, + { + .extent[0] = { + .first = 0, + .lower_first = 0, + .count = 4294967295U, + }, + }, + }, + .ns.count = REFCOUNT_INIT(3), + .owner = GLOBAL_ROOT_UID, + .group = GLOBAL_ROOT_GID, + .ns.inum = PROC_USER_INIT_INO, +#ifdef CONFIG_USER_NS + .ns.ops = &userns_operations, +#endif + .flags = USERNS_INIT_FLAGS, +#ifdef CONFIG_KEYS + .keyring_name_list = LIST_HEAD_INIT(init_user_ns.keyring_name_list), + .keyring_sem = __RWSEM_INITIALIZER(init_user_ns.keyring_sem), +#endif +}; +EXPORT_SYMBOL_GPL(init_user_ns); + +/* + * UID task count cache, to get fast user lookup in "alloc_uid" + * when changing user ID's (ie setuid() and friends). + */ + +#define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 7) +#define UIDHASH_SZ (1 << UIDHASH_BITS) +#define UIDHASH_MASK (UIDHASH_SZ - 1) +#define __uidhashfn(uid) (((uid >> UIDHASH_BITS) + uid) & UIDHASH_MASK) +#define uidhashentry(uid) (uidhash_table + __uidhashfn((__kuid_val(uid)))) + +static struct kmem_cache *uid_cachep; +static struct hlist_head uidhash_table[UIDHASH_SZ]; + +/* + * The uidhash_lock is mostly taken from process context, but it is + * occasionally also taken from softirq/tasklet context, when + * task-structs get RCU-freed. Hence all locking must be softirq-safe. + * But free_uid() is also called with local interrupts disabled, and running + * local_bh_enable() with local interrupts disabled is an error - we'll run + * softirq callbacks, and they can unconditionally enable interrupts, and + * the caller of free_uid() didn't expect that.. + */ +static DEFINE_SPINLOCK(uidhash_lock); + +/* root_user.__count is 1, for init task cred */ +struct user_struct root_user = { + .__count = REFCOUNT_INIT(1), + .uid = GLOBAL_ROOT_UID, + .ratelimit = RATELIMIT_STATE_INIT(root_user.ratelimit, 0, 0), +}; + +/* + * These routines must be called with the uidhash spinlock held! + */ +static void uid_hash_insert(struct user_struct *up, struct hlist_head *hashent) +{ + hlist_add_head(&up->uidhash_node, hashent); +} + +static void uid_hash_remove(struct user_struct *up) +{ + hlist_del_init(&up->uidhash_node); +} + +static struct user_struct *uid_hash_find(kuid_t uid, struct hlist_head *hashent) +{ + struct user_struct *user; + + hlist_for_each_entry(user, hashent, uidhash_node) { + if (uid_eq(user->uid, uid)) { + refcount_inc(&user->__count); + return user; + } + } + + return NULL; +} + +static int user_epoll_alloc(struct user_struct *up) +{ +#ifdef CONFIG_EPOLL + return percpu_counter_init(&up->epoll_watches, 0, GFP_KERNEL); +#else + return 0; +#endif +} + +static void user_epoll_free(struct user_struct *up) +{ +#ifdef CONFIG_EPOLL + percpu_counter_destroy(&up->epoll_watches); +#endif +} + +/* IRQs are disabled and uidhash_lock is held upon function entry. + * IRQ state (as stored in flags) is restored and uidhash_lock released + * upon function exit. + */ +static void free_user(struct user_struct *up, unsigned long flags) + __releases(&uidhash_lock) +{ + uid_hash_remove(up); + spin_unlock_irqrestore(&uidhash_lock, flags); + user_epoll_free(up); + kmem_cache_free(uid_cachep, up); +} + +/* + * Locate the user_struct for the passed UID. If found, take a ref on it. The + * caller must undo that ref with free_uid(). + * + * If the user_struct could not be found, return NULL. + */ +struct user_struct *find_user(kuid_t uid) +{ + struct user_struct *ret; + unsigned long flags; + + spin_lock_irqsave(&uidhash_lock, flags); + ret = uid_hash_find(uid, uidhashentry(uid)); + spin_unlock_irqrestore(&uidhash_lock, flags); + return ret; +} + +void free_uid(struct user_struct *up) +{ + unsigned long flags; + + if (!up) + return; + + if (refcount_dec_and_lock_irqsave(&up->__count, &uidhash_lock, &flags)) + free_user(up, flags); +} +EXPORT_SYMBOL_GPL(free_uid); + +struct user_struct *alloc_uid(kuid_t uid) +{ + struct hlist_head *hashent = uidhashentry(uid); + struct user_struct *up, *new; + + spin_lock_irq(&uidhash_lock); + up = uid_hash_find(uid, hashent); + spin_unlock_irq(&uidhash_lock); + + if (!up) { + new = kmem_cache_zalloc(uid_cachep, GFP_KERNEL); + if (!new) + return NULL; + + new->uid = uid; + refcount_set(&new->__count, 1); + if (user_epoll_alloc(new)) { + kmem_cache_free(uid_cachep, new); + return NULL; + } + ratelimit_state_init(&new->ratelimit, HZ, 100); + ratelimit_set_flags(&new->ratelimit, RATELIMIT_MSG_ON_RELEASE); + + /* + * Before adding this, check whether we raced + * on adding the same user already.. + */ + spin_lock_irq(&uidhash_lock); + up = uid_hash_find(uid, hashent); + if (up) { + user_epoll_free(new); + kmem_cache_free(uid_cachep, new); + } else { + uid_hash_insert(new, hashent); + up = new; + } + spin_unlock_irq(&uidhash_lock); + } + + return up; +} + +static int __init uid_cache_init(void) +{ + int n; + + uid_cachep = kmem_cache_create("uid_cache", sizeof(struct user_struct), + 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); + + for(n = 0; n < UIDHASH_SZ; ++n) + INIT_HLIST_HEAD(uidhash_table + n); + + if (user_epoll_alloc(&root_user)) + panic("root_user epoll percpu counter alloc failed"); + + /* Insert the root user immediately (init already runs as root) */ + spin_lock_irq(&uidhash_lock); + uid_hash_insert(&root_user, uidhashentry(GLOBAL_ROOT_UID)); + spin_unlock_irq(&uidhash_lock); + + return 0; +} +subsys_initcall(uid_cache_init); -- cgit v1.2.3