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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 /arch/arc/kernel/kprobes.c
downloadlinux-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 'arch/arc/kernel/kprobes.c')
-rw-r--r--arch/arc/kernel/kprobes.c415
1 files changed, 415 insertions, 0 deletions
diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c
new file mode 100644
index 000000000..e71d64119
--- /dev/null
+++ b/arch/arc/kernel/kprobes.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/types.h>
+#include <linux/kprobes.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kdebug.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/current.h>
+#include <asm/disasm.h>
+
+#define MIN_STACK_SIZE(addr) min((unsigned long)MAX_STACK_SIZE, \
+ (unsigned long)current_thread_info() + THREAD_SIZE - (addr))
+
+DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
+DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
+
+int __kprobes arch_prepare_kprobe(struct kprobe *p)
+{
+ /* Attempt to probe at unaligned address */
+ if ((unsigned long)p->addr & 0x01)
+ return -EINVAL;
+
+ /* Address should not be in exception handling code */
+
+ p->ainsn.is_short = is_short_instr((unsigned long)p->addr);
+ p->opcode = *p->addr;
+
+ return 0;
+}
+
+void __kprobes arch_arm_kprobe(struct kprobe *p)
+{
+ *p->addr = UNIMP_S_INSTRUCTION;
+
+ flush_icache_range((unsigned long)p->addr,
+ (unsigned long)p->addr + sizeof(kprobe_opcode_t));
+}
+
+void __kprobes arch_disarm_kprobe(struct kprobe *p)
+{
+ *p->addr = p->opcode;
+
+ flush_icache_range((unsigned long)p->addr,
+ (unsigned long)p->addr + sizeof(kprobe_opcode_t));
+}
+
+void __kprobes arch_remove_kprobe(struct kprobe *p)
+{
+ arch_disarm_kprobe(p);
+
+ /* Can we remove the kprobe in the middle of kprobe handling? */
+ if (p->ainsn.t1_addr) {
+ *(p->ainsn.t1_addr) = p->ainsn.t1_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t1_addr,
+ (unsigned long)p->ainsn.t1_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t1_addr = NULL;
+ }
+
+ if (p->ainsn.t2_addr) {
+ *(p->ainsn.t2_addr) = p->ainsn.t2_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t2_addr,
+ (unsigned long)p->ainsn.t2_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t2_addr = NULL;
+ }
+}
+
+static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
+{
+ kcb->prev_kprobe.kp = kprobe_running();
+ kcb->prev_kprobe.status = kcb->kprobe_status;
+}
+
+static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
+{
+ __this_cpu_write(current_kprobe, kcb->prev_kprobe.kp);
+ kcb->kprobe_status = kcb->prev_kprobe.status;
+}
+
+static inline void __kprobes set_current_kprobe(struct kprobe *p)
+{
+ __this_cpu_write(current_kprobe, p);
+}
+
+static void __kprobes resume_execution(struct kprobe *p, unsigned long addr,
+ struct pt_regs *regs)
+{
+ /* Remove the trap instructions inserted for single step and
+ * restore the original instructions
+ */
+ if (p->ainsn.t1_addr) {
+ *(p->ainsn.t1_addr) = p->ainsn.t1_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t1_addr,
+ (unsigned long)p->ainsn.t1_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t1_addr = NULL;
+ }
+
+ if (p->ainsn.t2_addr) {
+ *(p->ainsn.t2_addr) = p->ainsn.t2_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t2_addr,
+ (unsigned long)p->ainsn.t2_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t2_addr = NULL;
+ }
+
+ return;
+}
+
+static void __kprobes setup_singlestep(struct kprobe *p, struct pt_regs *regs)
+{
+ unsigned long next_pc;
+ unsigned long tgt_if_br = 0;
+ int is_branch;
+ unsigned long bta;
+
+ /* Copy the opcode back to the kprobe location and execute the
+ * instruction. Because of this we will not be able to get into the
+ * same kprobe until this kprobe is done
+ */
+ *(p->addr) = p->opcode;
+
+ flush_icache_range((unsigned long)p->addr,
+ (unsigned long)p->addr + sizeof(kprobe_opcode_t));
+
+ /* Now we insert the trap at the next location after this instruction to
+ * single step. If it is a branch we insert the trap at possible branch
+ * targets
+ */
+
+ bta = regs->bta;
+
+ if (regs->status32 & 0x40) {
+ /* We are in a delay slot with the branch taken */
+
+ next_pc = bta & ~0x01;
+
+ if (!p->ainsn.is_short) {
+ if (bta & 0x01)
+ regs->blink += 2;
+ else {
+ /* Branch not taken */
+ next_pc += 2;
+
+ /* next pc is taken from bta after executing the
+ * delay slot instruction
+ */
+ regs->bta += 2;
+ }
+ }
+
+ is_branch = 0;
+ } else
+ is_branch =
+ disasm_next_pc((unsigned long)p->addr, regs,
+ (struct callee_regs *) current->thread.callee_reg,
+ &next_pc, &tgt_if_br);
+
+ p->ainsn.t1_addr = (kprobe_opcode_t *) next_pc;
+ p->ainsn.t1_opcode = *(p->ainsn.t1_addr);
+ *(p->ainsn.t1_addr) = TRAP_S_2_INSTRUCTION;
+
+ flush_icache_range((unsigned long)p->ainsn.t1_addr,
+ (unsigned long)p->ainsn.t1_addr +
+ sizeof(kprobe_opcode_t));
+
+ if (is_branch) {
+ p->ainsn.t2_addr = (kprobe_opcode_t *) tgt_if_br;
+ p->ainsn.t2_opcode = *(p->ainsn.t2_addr);
+ *(p->ainsn.t2_addr) = TRAP_S_2_INSTRUCTION;
+
+ flush_icache_range((unsigned long)p->ainsn.t2_addr,
+ (unsigned long)p->ainsn.t2_addr +
+ sizeof(kprobe_opcode_t));
+ }
+}
+
+int __kprobes arc_kprobe_handler(unsigned long addr, struct pt_regs *regs)
+{
+ struct kprobe *p;
+ struct kprobe_ctlblk *kcb;
+
+ preempt_disable();
+
+ kcb = get_kprobe_ctlblk();
+ p = get_kprobe((unsigned long *)addr);
+
+ if (p) {
+ /*
+ * We have reentered the kprobe_handler, since another kprobe
+ * was hit while within the handler, we save the original
+ * kprobes and single step on the instruction of the new probe
+ * without calling any user handlers to avoid recursive
+ * kprobes.
+ */
+ if (kprobe_running()) {
+ save_previous_kprobe(kcb);
+ set_current_kprobe(p);
+ kprobes_inc_nmissed_count(p);
+ setup_singlestep(p, regs);
+ kcb->kprobe_status = KPROBE_REENTER;
+ return 1;
+ }
+
+ set_current_kprobe(p);
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+
+ /* If we have no pre-handler or it returned 0, we continue with
+ * normal processing. If we have a pre-handler and it returned
+ * non-zero - which means user handler setup registers to exit
+ * to another instruction, we must skip the single stepping.
+ */
+ if (!p->pre_handler || !p->pre_handler(p, regs)) {
+ setup_singlestep(p, regs);
+ kcb->kprobe_status = KPROBE_HIT_SS;
+ } else {
+ reset_current_kprobe();
+ preempt_enable_no_resched();
+ }
+
+ return 1;
+ }
+
+ /* no_kprobe: */
+ preempt_enable_no_resched();
+ return 0;
+}
+
+static int __kprobes arc_post_kprobe_handler(unsigned long addr,
+ struct pt_regs *regs)
+{
+ struct kprobe *cur = kprobe_running();
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ if (!cur)
+ return 0;
+
+ resume_execution(cur, addr, regs);
+
+ /* Rearm the kprobe */
+ arch_arm_kprobe(cur);
+
+ /*
+ * When we return from trap instruction we go to the next instruction
+ * We restored the actual instruction in resume_exectuiont and we to
+ * return to the same address and execute it
+ */
+ regs->ret = addr;
+
+ if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
+ kcb->kprobe_status = KPROBE_HIT_SSDONE;
+ cur->post_handler(cur, regs, 0);
+ }
+
+ if (kcb->kprobe_status == KPROBE_REENTER) {
+ restore_previous_kprobe(kcb);
+ goto out;
+ }
+
+ reset_current_kprobe();
+
+out:
+ preempt_enable_no_resched();
+ return 1;
+}
+
+/*
+ * Fault can be for the instruction being single stepped or for the
+ * pre/post handlers in the module.
+ * This is applicable for applications like user probes, where we have the
+ * probe in user space and the handlers in the kernel
+ */
+
+int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned long trapnr)
+{
+ struct kprobe *cur = kprobe_running();
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ switch (kcb->kprobe_status) {
+ case KPROBE_HIT_SS:
+ case KPROBE_REENTER:
+ /*
+ * We are here because the instruction being single stepped
+ * caused the fault. We reset the current kprobe and allow the
+ * exception handler as if it is regular exception. In our
+ * case it doesn't matter because the system will be halted
+ */
+ resume_execution(cur, (unsigned long)cur->addr, regs);
+
+ if (kcb->kprobe_status == KPROBE_REENTER)
+ restore_previous_kprobe(kcb);
+ else
+ reset_current_kprobe();
+
+ preempt_enable_no_resched();
+ break;
+
+ case KPROBE_HIT_ACTIVE:
+ case KPROBE_HIT_SSDONE:
+ /*
+ * We are here because the instructions in the pre/post handler
+ * caused the fault.
+ */
+
+ /*
+ * In case the user-specified fault handler returned zero,
+ * try to fix up.
+ */
+ if (fixup_exception(regs))
+ return 1;
+
+ /*
+ * fixup_exception() could not handle it,
+ * Let do_page_fault() fix it.
+ */
+ break;
+
+ default:
+ break;
+ }
+ return 0;
+}
+
+int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct die_args *args = data;
+ unsigned long addr = args->err;
+ int ret = NOTIFY_DONE;
+
+ switch (val) {
+ case DIE_IERR:
+ if (arc_kprobe_handler(addr, args->regs))
+ return NOTIFY_STOP;
+ break;
+
+ case DIE_TRAP:
+ if (arc_post_kprobe_handler(addr, args->regs))
+ return NOTIFY_STOP;
+ break;
+
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+static void __used kretprobe_trampoline_holder(void)
+{
+ __asm__ __volatile__(".global __kretprobe_trampoline\n"
+ "__kretprobe_trampoline:\n"
+ "nop\n");
+}
+
+void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+
+ ri->ret_addr = (kprobe_opcode_t *) regs->blink;
+ ri->fp = NULL;
+
+ /* Replace the return addr with trampoline addr */
+ regs->blink = (unsigned long)&__kretprobe_trampoline;
+}
+
+static int __kprobes trampoline_probe_handler(struct kprobe *p,
+ struct pt_regs *regs)
+{
+ regs->ret = __kretprobe_trampoline_handler(regs, NULL);
+
+ /* By returning a non zero value, we are telling the kprobe handler
+ * that we don't want the post_handler to run
+ */
+ return 1;
+}
+
+static struct kprobe trampoline_p = {
+ .addr = (kprobe_opcode_t *) &__kretprobe_trampoline,
+ .pre_handler = trampoline_probe_handler
+};
+
+int __init arch_init_kprobes(void)
+{
+ /* Registering the trampoline code for the kret probe */
+ return register_kprobe(&trampoline_p);
+}
+
+int __kprobes arch_trampoline_kprobe(struct kprobe *p)
+{
+ if (p->addr == (kprobe_opcode_t *) &__kretprobe_trampoline)
+ return 1;
+
+ return 0;
+}
+
+void trap_is_kprobe(unsigned long address, struct pt_regs *regs)
+{
+ notify_die(DIE_TRAP, "kprobe_trap", regs, address, 0, SIGTRAP);
+}