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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/x86/entry/vsyscall
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/x86/entry/vsyscall')
-rw-r--r--arch/x86/entry/vsyscall/Makefile6
-rw-r--r--arch/x86/entry/vsyscall/vsyscall_64.c398
-rw-r--r--arch/x86/entry/vsyscall/vsyscall_emu_64.S39
-rw-r--r--arch/x86/entry/vsyscall/vsyscall_trace.h30
4 files changed, 473 insertions, 0 deletions
diff --git a/arch/x86/entry/vsyscall/Makefile b/arch/x86/entry/vsyscall/Makefile
new file mode 100644
index 000000000..93c1b3e94
--- /dev/null
+++ b/arch/x86/entry/vsyscall/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the x86 low level vsyscall code
+#
+obj-$(CONFIG_X86_VSYSCALL_EMULATION) += vsyscall_64.o vsyscall_emu_64.o
+
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
new file mode 100644
index 000000000..4af81df13
--- /dev/null
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -0,0 +1,398 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012-2014 Andy Lutomirski <luto@amacapital.net>
+ *
+ * Based on the original implementation which is:
+ * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ * Copyright 2003 Andi Kleen, SuSE Labs.
+ *
+ * Parts of the original code have been moved to arch/x86/vdso/vma.c
+ *
+ * This file implements vsyscall emulation. vsyscalls are a legacy ABI:
+ * Userspace can request certain kernel services by calling fixed
+ * addresses. This concept is problematic:
+ *
+ * - It interferes with ASLR.
+ * - It's awkward to write code that lives in kernel addresses but is
+ * callable by userspace at fixed addresses.
+ * - The whole concept is impossible for 32-bit compat userspace.
+ * - UML cannot easily virtualize a vsyscall.
+ *
+ * As of mid-2014, I believe that there is no new userspace code that
+ * will use a vsyscall if the vDSO is present. I hope that there will
+ * soon be no new userspace code that will ever use a vsyscall.
+ *
+ * The code in this file emulates vsyscalls when notified of a page
+ * fault to a vsyscall address.
+ */
+
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/sched/signal.h>
+#include <linux/mm_types.h>
+#include <linux/syscalls.h>
+#include <linux/ratelimit.h>
+
+#include <asm/vsyscall.h>
+#include <asm/unistd.h>
+#include <asm/fixmap.h>
+#include <asm/traps.h>
+#include <asm/paravirt.h>
+
+#define CREATE_TRACE_POINTS
+#include "vsyscall_trace.h"
+
+static enum { EMULATE, XONLY, NONE } vsyscall_mode __ro_after_init =
+#ifdef CONFIG_LEGACY_VSYSCALL_NONE
+ NONE;
+#elif defined(CONFIG_LEGACY_VSYSCALL_XONLY)
+ XONLY;
+#else
+ #error VSYSCALL config is broken
+#endif
+
+static int __init vsyscall_setup(char *str)
+{
+ if (str) {
+ if (!strcmp("emulate", str))
+ vsyscall_mode = EMULATE;
+ else if (!strcmp("xonly", str))
+ vsyscall_mode = XONLY;
+ else if (!strcmp("none", str))
+ vsyscall_mode = NONE;
+ else
+ return -EINVAL;
+
+ return 0;
+ }
+
+ return -EINVAL;
+}
+early_param("vsyscall", vsyscall_setup);
+
+static void warn_bad_vsyscall(const char *level, struct pt_regs *regs,
+ const char *message)
+{
+ if (!show_unhandled_signals)
+ return;
+
+ printk_ratelimited("%s%s[%d] %s ip:%lx cs:%lx sp:%lx ax:%lx si:%lx di:%lx\n",
+ level, current->comm, task_pid_nr(current),
+ message, regs->ip, regs->cs,
+ regs->sp, regs->ax, regs->si, regs->di);
+}
+
+static int addr_to_vsyscall_nr(unsigned long addr)
+{
+ int nr;
+
+ if ((addr & ~0xC00UL) != VSYSCALL_ADDR)
+ return -EINVAL;
+
+ nr = (addr & 0xC00UL) >> 10;
+ if (nr >= 3)
+ return -EINVAL;
+
+ return nr;
+}
+
+static bool write_ok_or_segv(unsigned long ptr, size_t size)
+{
+ /*
+ * XXX: if access_ok, get_user, and put_user handled
+ * sig_on_uaccess_err, this could go away.
+ */
+
+ if (!access_ok((void __user *)ptr, size)) {
+ struct thread_struct *thread = &current->thread;
+
+ thread->error_code = X86_PF_USER | X86_PF_WRITE;
+ thread->cr2 = ptr;
+ thread->trap_nr = X86_TRAP_PF;
+
+ force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)ptr);
+ return false;
+ } else {
+ return true;
+ }
+}
+
+bool emulate_vsyscall(unsigned long error_code,
+ struct pt_regs *regs, unsigned long address)
+{
+ struct task_struct *tsk;
+ unsigned long caller;
+ int vsyscall_nr, syscall_nr, tmp;
+ int prev_sig_on_uaccess_err;
+ long ret;
+ unsigned long orig_dx;
+
+ /* Write faults or kernel-privilege faults never get fixed up. */
+ if ((error_code & (X86_PF_WRITE | X86_PF_USER)) != X86_PF_USER)
+ return false;
+
+ if (!(error_code & X86_PF_INSTR)) {
+ /* Failed vsyscall read */
+ if (vsyscall_mode == EMULATE)
+ return false;
+
+ /*
+ * User code tried and failed to read the vsyscall page.
+ */
+ warn_bad_vsyscall(KERN_INFO, regs, "vsyscall read attempt denied -- look up the vsyscall kernel parameter if you need a workaround");
+ return false;
+ }
+
+ /*
+ * No point in checking CS -- the only way to get here is a user mode
+ * trap to a high address, which means that we're in 64-bit user code.
+ */
+
+ WARN_ON_ONCE(address != regs->ip);
+
+ if (vsyscall_mode == NONE) {
+ warn_bad_vsyscall(KERN_INFO, regs,
+ "vsyscall attempted with vsyscall=none");
+ return false;
+ }
+
+ vsyscall_nr = addr_to_vsyscall_nr(address);
+
+ trace_emulate_vsyscall(vsyscall_nr);
+
+ if (vsyscall_nr < 0) {
+ warn_bad_vsyscall(KERN_WARNING, regs,
+ "misaligned vsyscall (exploit attempt or buggy program) -- look up the vsyscall kernel parameter if you need a workaround");
+ goto sigsegv;
+ }
+
+ if (get_user(caller, (unsigned long __user *)regs->sp) != 0) {
+ warn_bad_vsyscall(KERN_WARNING, regs,
+ "vsyscall with bad stack (exploit attempt?)");
+ goto sigsegv;
+ }
+
+ tsk = current;
+
+ /*
+ * Check for access_ok violations and find the syscall nr.
+ *
+ * NULL is a valid user pointer (in the access_ok sense) on 32-bit and
+ * 64-bit, so we don't need to special-case it here. For all the
+ * vsyscalls, NULL means "don't write anything" not "write it at
+ * address 0".
+ */
+ switch (vsyscall_nr) {
+ case 0:
+ if (!write_ok_or_segv(regs->di, sizeof(struct __kernel_old_timeval)) ||
+ !write_ok_or_segv(regs->si, sizeof(struct timezone))) {
+ ret = -EFAULT;
+ goto check_fault;
+ }
+
+ syscall_nr = __NR_gettimeofday;
+ break;
+
+ case 1:
+ if (!write_ok_or_segv(regs->di, sizeof(__kernel_old_time_t))) {
+ ret = -EFAULT;
+ goto check_fault;
+ }
+
+ syscall_nr = __NR_time;
+ break;
+
+ case 2:
+ if (!write_ok_or_segv(regs->di, sizeof(unsigned)) ||
+ !write_ok_or_segv(regs->si, sizeof(unsigned))) {
+ ret = -EFAULT;
+ goto check_fault;
+ }
+
+ syscall_nr = __NR_getcpu;
+ break;
+ }
+
+ /*
+ * Handle seccomp. regs->ip must be the original value.
+ * See seccomp_send_sigsys and Documentation/userspace-api/seccomp_filter.rst.
+ *
+ * We could optimize the seccomp disabled case, but performance
+ * here doesn't matter.
+ */
+ regs->orig_ax = syscall_nr;
+ regs->ax = -ENOSYS;
+ tmp = secure_computing();
+ if ((!tmp && regs->orig_ax != syscall_nr) || regs->ip != address) {
+ warn_bad_vsyscall(KERN_DEBUG, regs,
+ "seccomp tried to change syscall nr or ip");
+ force_exit_sig(SIGSYS);
+ return true;
+ }
+ regs->orig_ax = -1;
+ if (tmp)
+ goto do_ret; /* skip requested */
+
+ /*
+ * With a real vsyscall, page faults cause SIGSEGV. We want to
+ * preserve that behavior to make writing exploits harder.
+ */
+ prev_sig_on_uaccess_err = current->thread.sig_on_uaccess_err;
+ current->thread.sig_on_uaccess_err = 1;
+
+ ret = -EFAULT;
+ switch (vsyscall_nr) {
+ case 0:
+ /* this decodes regs->di and regs->si on its own */
+ ret = __x64_sys_gettimeofday(regs);
+ break;
+
+ case 1:
+ /* this decodes regs->di on its own */
+ ret = __x64_sys_time(regs);
+ break;
+
+ case 2:
+ /* while we could clobber regs->dx, we didn't in the past... */
+ orig_dx = regs->dx;
+ regs->dx = 0;
+ /* this decodes regs->di, regs->si and regs->dx on its own */
+ ret = __x64_sys_getcpu(regs);
+ regs->dx = orig_dx;
+ break;
+ }
+
+ current->thread.sig_on_uaccess_err = prev_sig_on_uaccess_err;
+
+check_fault:
+ if (ret == -EFAULT) {
+ /* Bad news -- userspace fed a bad pointer to a vsyscall. */
+ warn_bad_vsyscall(KERN_INFO, regs,
+ "vsyscall fault (exploit attempt?)");
+
+ /*
+ * If we failed to generate a signal for any reason,
+ * generate one here. (This should be impossible.)
+ */
+ if (WARN_ON_ONCE(!sigismember(&tsk->pending.signal, SIGBUS) &&
+ !sigismember(&tsk->pending.signal, SIGSEGV)))
+ goto sigsegv;
+
+ return true; /* Don't emulate the ret. */
+ }
+
+ regs->ax = ret;
+
+do_ret:
+ /* Emulate a ret instruction. */
+ regs->ip = caller;
+ regs->sp += 8;
+ return true;
+
+sigsegv:
+ force_sig(SIGSEGV);
+ return true;
+}
+
+/*
+ * A pseudo VMA to allow ptrace access for the vsyscall page. This only
+ * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
+ * not need special handling anymore:
+ */
+static const char *gate_vma_name(struct vm_area_struct *vma)
+{
+ return "[vsyscall]";
+}
+static const struct vm_operations_struct gate_vma_ops = {
+ .name = gate_vma_name,
+};
+static struct vm_area_struct gate_vma __ro_after_init = {
+ .vm_start = VSYSCALL_ADDR,
+ .vm_end = VSYSCALL_ADDR + PAGE_SIZE,
+ .vm_page_prot = PAGE_READONLY_EXEC,
+ .vm_flags = VM_READ | VM_EXEC,
+ .vm_ops = &gate_vma_ops,
+};
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+#ifdef CONFIG_COMPAT
+ if (!mm || !(mm->context.flags & MM_CONTEXT_HAS_VSYSCALL))
+ return NULL;
+#endif
+ if (vsyscall_mode == NONE)
+ return NULL;
+ return &gate_vma;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+ struct vm_area_struct *vma = get_gate_vma(mm);
+
+ if (!vma)
+ return 0;
+
+ return (addr >= vma->vm_start) && (addr < vma->vm_end);
+}
+
+/*
+ * Use this when you have no reliable mm, typically from interrupt
+ * context. It is less reliable than using a task's mm and may give
+ * false positives.
+ */
+int in_gate_area_no_mm(unsigned long addr)
+{
+ return vsyscall_mode != NONE && (addr & PAGE_MASK) == VSYSCALL_ADDR;
+}
+
+/*
+ * The VSYSCALL page is the only user-accessible page in the kernel address
+ * range. Normally, the kernel page tables can have _PAGE_USER clear, but
+ * the tables covering VSYSCALL_ADDR need _PAGE_USER set if vsyscalls
+ * are enabled.
+ *
+ * Some day we may create a "minimal" vsyscall mode in which we emulate
+ * vsyscalls but leave the page not present. If so, we skip calling
+ * this.
+ */
+void __init set_vsyscall_pgtable_user_bits(pgd_t *root)
+{
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ pgd = pgd_offset_pgd(root, VSYSCALL_ADDR);
+ set_pgd(pgd, __pgd(pgd_val(*pgd) | _PAGE_USER));
+ p4d = p4d_offset(pgd, VSYSCALL_ADDR);
+#if CONFIG_PGTABLE_LEVELS >= 5
+ set_p4d(p4d, __p4d(p4d_val(*p4d) | _PAGE_USER));
+#endif
+ pud = pud_offset(p4d, VSYSCALL_ADDR);
+ set_pud(pud, __pud(pud_val(*pud) | _PAGE_USER));
+ pmd = pmd_offset(pud, VSYSCALL_ADDR);
+ set_pmd(pmd, __pmd(pmd_val(*pmd) | _PAGE_USER));
+}
+
+void __init map_vsyscall(void)
+{
+ extern char __vsyscall_page;
+ unsigned long physaddr_vsyscall = __pa_symbol(&__vsyscall_page);
+
+ /*
+ * For full emulation, the page needs to exist for real. In
+ * execute-only mode, there is no PTE at all backing the vsyscall
+ * page.
+ */
+ if (vsyscall_mode == EMULATE) {
+ __set_fixmap(VSYSCALL_PAGE, physaddr_vsyscall,
+ PAGE_KERNEL_VVAR);
+ set_vsyscall_pgtable_user_bits(swapper_pg_dir);
+ }
+
+ if (vsyscall_mode == XONLY)
+ gate_vma.vm_flags = VM_EXEC;
+
+ BUILD_BUG_ON((unsigned long)__fix_to_virt(VSYSCALL_PAGE) !=
+ (unsigned long)VSYSCALL_ADDR);
+}
diff --git a/arch/x86/entry/vsyscall/vsyscall_emu_64.S b/arch/x86/entry/vsyscall/vsyscall_emu_64.S
new file mode 100644
index 000000000..ef2dd1827
--- /dev/null
+++ b/arch/x86/entry/vsyscall/vsyscall_emu_64.S
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * vsyscall_emu_64.S: Vsyscall emulation page
+ *
+ * Copyright (c) 2011 Andy Lutomirski
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/irq_vectors.h>
+#include <asm/page_types.h>
+#include <asm/unistd_64.h>
+
+__PAGE_ALIGNED_DATA
+ .globl __vsyscall_page
+ .balign PAGE_SIZE, 0xcc
+ .type __vsyscall_page, @object
+__vsyscall_page:
+
+ mov $__NR_gettimeofday, %rax
+ syscall
+ ret
+ int3
+
+ .balign 1024, 0xcc
+ mov $__NR_time, %rax
+ syscall
+ ret
+ int3
+
+ .balign 1024, 0xcc
+ mov $__NR_getcpu, %rax
+ syscall
+ ret
+ int3
+
+ .balign 4096, 0xcc
+
+ .size __vsyscall_page, 4096
diff --git a/arch/x86/entry/vsyscall/vsyscall_trace.h b/arch/x86/entry/vsyscall/vsyscall_trace.h
new file mode 100644
index 000000000..3c3f9765a
--- /dev/null
+++ b/arch/x86/entry/vsyscall/vsyscall_trace.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM vsyscall
+
+#if !defined(__VSYSCALL_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define __VSYSCALL_TRACE_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(emulate_vsyscall,
+
+ TP_PROTO(int nr),
+
+ TP_ARGS(nr),
+
+ TP_STRUCT__entry(__field(int, nr)),
+
+ TP_fast_assign(
+ __entry->nr = nr;
+ ),
+
+ TP_printk("nr = %d", __entry->nr)
+);
+
+#endif
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../arch/x86/entry/vsyscall/
+#define TRACE_INCLUDE_FILE vsyscall_trace
+#include <trace/define_trace.h>