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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /lib/textsearch.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
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diff --git a/lib/textsearch.c b/lib/textsearch.c
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * lib/textsearch.c Generic text search interface
+ *
+ * Authors: Thomas Graf <tgraf@suug.ch>
+ * Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * ==========================================================================
+ */
+
+/**
+ * DOC: ts_intro
+ * INTRODUCTION
+ *
+ * The textsearch infrastructure provides text searching facilities for
+ * both linear and non-linear data. Individual search algorithms are
+ * implemented in modules and chosen by the user.
+ *
+ * ARCHITECTURE
+ *
+ * .. code-block:: none
+ *
+ * User
+ * +----------------+
+ * | finish()|<--------------(6)-----------------+
+ * |get_next_block()|<--------------(5)---------------+ |
+ * | | Algorithm | |
+ * | | +------------------------------+
+ * | | | init() find() destroy() |
+ * | | +------------------------------+
+ * | | Core API ^ ^ ^
+ * | | +---------------+ (2) (4) (8)
+ * | (1)|----->| prepare() |---+ | |
+ * | (3)|----->| find()/next() |-----------+ |
+ * | (7)|----->| destroy() |----------------------+
+ * +----------------+ +---------------+
+ *
+ * (1) User configures a search by calling textsearch_prepare() specifying
+ * the search parameters such as the pattern and algorithm name.
+ * (2) Core requests the algorithm to allocate and initialize a search
+ * configuration according to the specified parameters.
+ * (3) User starts the search(es) by calling textsearch_find() or
+ * textsearch_next() to fetch subsequent occurrences. A state variable
+ * is provided to the algorithm to store persistent variables.
+ * (4) Core eventually resets the search offset and forwards the find()
+ * request to the algorithm.
+ * (5) Algorithm calls get_next_block() provided by the user continuously
+ * to fetch the data to be searched in block by block.
+ * (6) Algorithm invokes finish() after the last call to get_next_block
+ * to clean up any leftovers from get_next_block. (Optional)
+ * (7) User destroys the configuration by calling textsearch_destroy().
+ * (8) Core notifies the algorithm to destroy algorithm specific
+ * allocations. (Optional)
+ *
+ * USAGE
+ *
+ * Before a search can be performed, a configuration must be created
+ * by calling textsearch_prepare() specifying the searching algorithm,
+ * the pattern to look for and flags. As a flag, you can set TS_IGNORECASE
+ * to perform case insensitive matching. But it might slow down
+ * performance of algorithm, so you should use it at own your risk.
+ * The returned configuration may then be used for an arbitrary
+ * amount of times and even in parallel as long as a separate struct
+ * ts_state variable is provided to every instance.
+ *
+ * The actual search is performed by either calling
+ * textsearch_find_continuous() for linear data or by providing
+ * an own get_next_block() implementation and
+ * calling textsearch_find(). Both functions return
+ * the position of the first occurrence of the pattern or UINT_MAX if
+ * no match was found. Subsequent occurrences can be found by calling
+ * textsearch_next() regardless of the linearity of the data.
+ *
+ * Once you're done using a configuration it must be given back via
+ * textsearch_destroy.
+ *
+ * EXAMPLE::
+ *
+ * int pos;
+ * struct ts_config *conf;
+ * struct ts_state state;
+ * const char *pattern = "chicken";
+ * const char *example = "We dance the funky chicken";
+ *
+ * conf = textsearch_prepare("kmp", pattern, strlen(pattern),
+ * GFP_KERNEL, TS_AUTOLOAD);
+ * if (IS_ERR(conf)) {
+ * err = PTR_ERR(conf);
+ * goto errout;
+ * }
+ *
+ * pos = textsearch_find_continuous(conf, &state, example, strlen(example));
+ * if (pos != UINT_MAX)
+ * panic("Oh my god, dancing chickens at %d\n", pos);
+ *
+ * textsearch_destroy(conf);
+ */
+/* ========================================================================== */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/err.h>
+#include <linux/textsearch.h>
+#include <linux/slab.h>
+
+static LIST_HEAD(ts_ops);
+static DEFINE_SPINLOCK(ts_mod_lock);
+
+static inline struct ts_ops *lookup_ts_algo(const char *name)
+{
+ struct ts_ops *o;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(o, &ts_ops, list) {
+ if (!strcmp(name, o->name)) {
+ if (!try_module_get(o->owner))
+ o = NULL;
+ rcu_read_unlock();
+ return o;
+ }
+ }
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+/**
+ * textsearch_register - register a textsearch module
+ * @ops: operations lookup table
+ *
+ * This function must be called by textsearch modules to announce
+ * their presence. The specified &@ops must have %name set to a
+ * unique identifier and the callbacks find(), init(), get_pattern(),
+ * and get_pattern_len() must be implemented.
+ *
+ * Returns 0 or -EEXISTS if another module has already registered
+ * with same name.
+ */
+int textsearch_register(struct ts_ops *ops)
+{
+ int err = -EEXIST;
+ struct ts_ops *o;
+
+ if (ops->name == NULL || ops->find == NULL || ops->init == NULL ||
+ ops->get_pattern == NULL || ops->get_pattern_len == NULL)
+ return -EINVAL;
+
+ spin_lock(&ts_mod_lock);
+ list_for_each_entry(o, &ts_ops, list) {
+ if (!strcmp(ops->name, o->name))
+ goto errout;
+ }
+
+ list_add_tail_rcu(&ops->list, &ts_ops);
+ err = 0;
+errout:
+ spin_unlock(&ts_mod_lock);
+ return err;
+}
+EXPORT_SYMBOL(textsearch_register);
+
+/**
+ * textsearch_unregister - unregister a textsearch module
+ * @ops: operations lookup table
+ *
+ * This function must be called by textsearch modules to announce
+ * their disappearance for examples when the module gets unloaded.
+ * The &ops parameter must be the same as the one during the
+ * registration.
+ *
+ * Returns 0 on success or -ENOENT if no matching textsearch
+ * registration was found.
+ */
+int textsearch_unregister(struct ts_ops *ops)
+{
+ int err = 0;
+ struct ts_ops *o;
+
+ spin_lock(&ts_mod_lock);
+ list_for_each_entry(o, &ts_ops, list) {
+ if (o == ops) {
+ list_del_rcu(&o->list);
+ goto out;
+ }
+ }
+
+ err = -ENOENT;
+out:
+ spin_unlock(&ts_mod_lock);
+ return err;
+}
+EXPORT_SYMBOL(textsearch_unregister);
+
+struct ts_linear_state
+{
+ unsigned int len;
+ const void *data;
+};
+
+static unsigned int get_linear_data(unsigned int consumed, const u8 **dst,
+ struct ts_config *conf,
+ struct ts_state *state)
+{
+ struct ts_linear_state *st = (struct ts_linear_state *) state->cb;
+
+ if (likely(consumed < st->len)) {
+ *dst = st->data + consumed;
+ return st->len - consumed;
+ }
+
+ return 0;
+}
+
+/**
+ * textsearch_find_continuous - search a pattern in continuous/linear data
+ * @conf: search configuration
+ * @state: search state
+ * @data: data to search in
+ * @len: length of data
+ *
+ * A simplified version of textsearch_find() for continuous/linear data.
+ * Call textsearch_next() to retrieve subsequent matches.
+ *
+ * Returns the position of first occurrence of the pattern or
+ * %UINT_MAX if no occurrence was found.
+ */
+unsigned int textsearch_find_continuous(struct ts_config *conf,
+ struct ts_state *state,
+ const void *data, unsigned int len)
+{
+ struct ts_linear_state *st = (struct ts_linear_state *) state->cb;
+
+ conf->get_next_block = get_linear_data;
+ st->data = data;
+ st->len = len;
+
+ return textsearch_find(conf, state);
+}
+EXPORT_SYMBOL(textsearch_find_continuous);
+
+/**
+ * textsearch_prepare - Prepare a search
+ * @algo: name of search algorithm
+ * @pattern: pattern data
+ * @len: length of pattern
+ * @gfp_mask: allocation mask
+ * @flags: search flags
+ *
+ * Looks up the search algorithm module and creates a new textsearch
+ * configuration for the specified pattern.
+ *
+ * Note: The format of the pattern may not be compatible between
+ * the various search algorithms.
+ *
+ * Returns a new textsearch configuration according to the specified
+ * parameters or a ERR_PTR(). If a zero length pattern is passed, this
+ * function returns EINVAL.
+ */
+struct ts_config *textsearch_prepare(const char *algo, const void *pattern,
+ unsigned int len, gfp_t gfp_mask, int flags)
+{
+ int err = -ENOENT;
+ struct ts_config *conf;
+ struct ts_ops *ops;
+
+ if (len == 0)
+ return ERR_PTR(-EINVAL);
+
+ ops = lookup_ts_algo(algo);
+#ifdef CONFIG_MODULES
+ /*
+ * Why not always autoload you may ask. Some users are
+ * in a situation where requesting a module may deadlock,
+ * especially when the module is located on a NFS mount.
+ */
+ if (ops == NULL && flags & TS_AUTOLOAD) {
+ request_module("ts_%s", algo);
+ ops = lookup_ts_algo(algo);
+ }
+#endif
+
+ if (ops == NULL)
+ goto errout;
+
+ conf = ops->init(pattern, len, gfp_mask, flags);
+ if (IS_ERR(conf)) {
+ err = PTR_ERR(conf);
+ goto errout;
+ }
+
+ conf->ops = ops;
+ return conf;
+
+errout:
+ if (ops)
+ module_put(ops->owner);
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(textsearch_prepare);
+
+/**
+ * textsearch_destroy - destroy a search configuration
+ * @conf: search configuration
+ *
+ * Releases all references of the configuration and frees
+ * up the memory.
+ */
+void textsearch_destroy(struct ts_config *conf)
+{
+ if (conf->ops) {
+ if (conf->ops->destroy)
+ conf->ops->destroy(conf);
+ module_put(conf->ops->owner);
+ }
+
+ kfree(conf);
+}
+EXPORT_SYMBOL(textsearch_destroy);