mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-09 20:14:09 +08:00
a1e1eddef2
* for-next/misc: : Miscellaneous patches arm64/sve: Add compile time checks for SVE hooks in generic functions arm64/kernel/probes: Use BUG_ON instead of if condition followed by BUG. arm64/sve: Remove redundant system_supports_sve() tests arm64: mte: Remove unused mte_assign_mem_tag_range() arm64: Add __init section marker to some functions arm64/sve: Rework SVE access trap to convert state in registers docs: arm64: Fix a grammar error arm64: smp: Add missing prototype for some smp.c functions arm64: setup: name `tcr` register arm64: setup: name `mair` register arm64: stacktrace: Move start_backtrace() out of the header arm64: barrier: Remove spec_bar() macro arm64: entry: remove test_irqs_unmasked macro ARM64: enable GENERIC_FIND_FIRST_BIT arm64: defconfig: Use DEBUG_INFO_REDUCED * for-next/kselftest: : Various kselftests for arm64 kselftest: arm64: Add BTI tests kselftest/arm64: mte: Report filename on failing temp file creation kselftest/arm64: mte: Fix clang warning kselftest/arm64: mte: Makefile: Fix clang compilation kselftest/arm64: mte: Output warning about failing compiler kselftest/arm64: mte: Use cross-compiler if specified kselftest/arm64: mte: Fix MTE feature detection kselftest/arm64: mte: common: Fix write() warnings kselftest/arm64: mte: user_mem: Fix write() warning kselftest/arm64: mte: ksm_options: Fix fscanf warning kselftest/arm64: mte: Fix pthread linking kselftest/arm64: mte: Fix compilation with native compiler * for-next/xntable: : Add hierarchical XN permissions for all page tables arm64: mm: use XN table mapping attributes for user/kernel mappings arm64: mm: use XN table mapping attributes for the linear region arm64: mm: add missing P4D definitions and use them consistently * for-next/vdso: : Minor improvements to the compat vdso and sigpage arm64: compat: Poison the compat sigpage arm64: vdso: Avoid ISB after reading from cntvct_el0 arm64: compat: Allow signal page to be remapped arm64: vdso: Remove redundant calls to flush_dcache_page() arm64: vdso: Use GFP_KERNEL for allocating compat vdso and signal pages * for-next/fiq: : Support arm64 FIQ controller registration arm64: irq: allow FIQs to be handled arm64: Always keep DAIF.[IF] in sync arm64: entry: factor irq triage logic into macros arm64: irq: rework root IRQ handler registration arm64: don't use GENERIC_IRQ_MULTI_HANDLER genirq: Allow architectures to override set_handle_irq() fallback * for-next/epan: : Support for Enhanced PAN (execute-only permissions) arm64: Support execute-only permissions with Enhanced PAN * for-next/kasan-vmalloc: : Support CONFIG_KASAN_VMALLOC on arm64 arm64: Kconfig: select KASAN_VMALLOC if KANSAN_GENERIC is enabled arm64: kaslr: support randomized module area with KASAN_VMALLOC arm64: Kconfig: support CONFIG_KASAN_VMALLOC arm64: kasan: abstract _text and _end to KERNEL_START/END arm64: kasan: don't populate vmalloc area for CONFIG_KASAN_VMALLOC * for-next/fgt-boot-init: : Booting clarifications and fine grained traps setup arm64: Require that system registers at all visible ELs be initialized arm64: Disable fine grained traps on boot arm64: Document requirements for fine grained traps at boot * for-next/vhe-only: : Dealing with VHE-only CPUs (a.k.a. M1) arm64: Get rid of CONFIG_ARM64_VHE arm64: Cope with CPUs stuck in VHE mode arm64: cpufeature: Allow early filtering of feature override * arm64/for-next/perf: arm64: perf: Remove redundant initialization in perf_event.c perf/arm_pmu_platform: Clean up with dev_printk perf/arm_pmu_platform: Fix error handling perf/arm_pmu_platform: Use dev_err_probe() for IRQ errors docs: perf: Address some html build warnings docs: perf: Add new description on HiSilicon uncore PMU v2 drivers/perf: hisi: Add support for HiSilicon PA PMU driver drivers/perf: hisi: Add support for HiSilicon SLLC PMU driver drivers/perf: hisi: Update DDRC PMU for programmable counter drivers/perf: hisi: Add new functions for HHA PMU drivers/perf: hisi: Add new functions for L3C PMU drivers/perf: hisi: Add PMU version for uncore PMU drivers. drivers/perf: hisi: Refactor code for more uncore PMUs drivers/perf: hisi: Remove unnecessary check of counter index drivers/perf: Simplify the SMMUv3 PMU event attributes drivers/perf: convert sysfs sprintf family to sysfs_emit drivers/perf: convert sysfs scnprintf family to sysfs_emit_at() and sysfs_emit() drivers/perf: convert sysfs snprintf family to sysfs_emit * for-next/neon-softirqs-disabled: : Run kernel mode SIMD with softirqs disabled arm64: fpsimd: run kernel mode NEON with softirqs disabled arm64: assembler: introduce wxN aliases for wN registers arm64: assembler: remove conditional NEON yield macros
478 lines
11 KiB
C
478 lines
11 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* VDSO implementations.
|
|
*
|
|
* Copyright (C) 2012 ARM Limited
|
|
*
|
|
* Author: Will Deacon <will.deacon@arm.com>
|
|
*/
|
|
|
|
#include <linux/cache.h>
|
|
#include <linux/clocksource.h>
|
|
#include <linux/elf.h>
|
|
#include <linux/err.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/time_namespace.h>
|
|
#include <linux/timekeeper_internal.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <vdso/datapage.h>
|
|
#include <vdso/helpers.h>
|
|
#include <vdso/vsyscall.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/signal32.h>
|
|
#include <asm/vdso.h>
|
|
|
|
extern char vdso_start[], vdso_end[];
|
|
extern char vdso32_start[], vdso32_end[];
|
|
|
|
enum vdso_abi {
|
|
VDSO_ABI_AA64,
|
|
VDSO_ABI_AA32,
|
|
};
|
|
|
|
enum vvar_pages {
|
|
VVAR_DATA_PAGE_OFFSET,
|
|
VVAR_TIMENS_PAGE_OFFSET,
|
|
VVAR_NR_PAGES,
|
|
};
|
|
|
|
struct vdso_abi_info {
|
|
const char *name;
|
|
const char *vdso_code_start;
|
|
const char *vdso_code_end;
|
|
unsigned long vdso_pages;
|
|
/* Data Mapping */
|
|
struct vm_special_mapping *dm;
|
|
/* Code Mapping */
|
|
struct vm_special_mapping *cm;
|
|
};
|
|
|
|
static struct vdso_abi_info vdso_info[] __ro_after_init = {
|
|
[VDSO_ABI_AA64] = {
|
|
.name = "vdso",
|
|
.vdso_code_start = vdso_start,
|
|
.vdso_code_end = vdso_end,
|
|
},
|
|
#ifdef CONFIG_COMPAT_VDSO
|
|
[VDSO_ABI_AA32] = {
|
|
.name = "vdso32",
|
|
.vdso_code_start = vdso32_start,
|
|
.vdso_code_end = vdso32_end,
|
|
},
|
|
#endif /* CONFIG_COMPAT_VDSO */
|
|
};
|
|
|
|
/*
|
|
* The vDSO data page.
|
|
*/
|
|
static union {
|
|
struct vdso_data data[CS_BASES];
|
|
u8 page[PAGE_SIZE];
|
|
} vdso_data_store __page_aligned_data;
|
|
struct vdso_data *vdso_data = vdso_data_store.data;
|
|
|
|
static int vdso_mremap(const struct vm_special_mapping *sm,
|
|
struct vm_area_struct *new_vma)
|
|
{
|
|
current->mm->context.vdso = (void *)new_vma->vm_start;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init __vdso_init(enum vdso_abi abi)
|
|
{
|
|
int i;
|
|
struct page **vdso_pagelist;
|
|
unsigned long pfn;
|
|
|
|
if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4)) {
|
|
pr_err("vDSO is not a valid ELF object!\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
vdso_info[abi].vdso_pages = (
|
|
vdso_info[abi].vdso_code_end -
|
|
vdso_info[abi].vdso_code_start) >>
|
|
PAGE_SHIFT;
|
|
|
|
vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
|
|
sizeof(struct page *),
|
|
GFP_KERNEL);
|
|
if (vdso_pagelist == NULL)
|
|
return -ENOMEM;
|
|
|
|
/* Grab the vDSO code pages. */
|
|
pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
|
|
|
|
for (i = 0; i < vdso_info[abi].vdso_pages; i++)
|
|
vdso_pagelist[i] = pfn_to_page(pfn + i);
|
|
|
|
vdso_info[abi].cm->pages = vdso_pagelist;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_TIME_NS
|
|
struct vdso_data *arch_get_vdso_data(void *vvar_page)
|
|
{
|
|
return (struct vdso_data *)(vvar_page);
|
|
}
|
|
|
|
/*
|
|
* The vvar mapping contains data for a specific time namespace, so when a task
|
|
* changes namespace we must unmap its vvar data for the old namespace.
|
|
* Subsequent faults will map in data for the new namespace.
|
|
*
|
|
* For more details see timens_setup_vdso_data().
|
|
*/
|
|
int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
|
|
{
|
|
struct mm_struct *mm = task->mm;
|
|
struct vm_area_struct *vma;
|
|
|
|
mmap_read_lock(mm);
|
|
|
|
for (vma = mm->mmap; vma; vma = vma->vm_next) {
|
|
unsigned long size = vma->vm_end - vma->vm_start;
|
|
|
|
if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA64].dm))
|
|
zap_page_range(vma, vma->vm_start, size);
|
|
#ifdef CONFIG_COMPAT_VDSO
|
|
if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA32].dm))
|
|
zap_page_range(vma, vma->vm_start, size);
|
|
#endif
|
|
}
|
|
|
|
mmap_read_unlock(mm);
|
|
return 0;
|
|
}
|
|
|
|
static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
|
|
{
|
|
if (likely(vma->vm_mm == current->mm))
|
|
return current->nsproxy->time_ns->vvar_page;
|
|
|
|
/*
|
|
* VM_PFNMAP | VM_IO protect .fault() handler from being called
|
|
* through interfaces like /proc/$pid/mem or
|
|
* process_vm_{readv,writev}() as long as there's no .access()
|
|
* in special_mapping_vmops.
|
|
* For more details check_vma_flags() and __access_remote_vm()
|
|
*/
|
|
WARN(1, "vvar_page accessed remotely");
|
|
|
|
return NULL;
|
|
}
|
|
#else
|
|
static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
|
|
struct vm_area_struct *vma, struct vm_fault *vmf)
|
|
{
|
|
struct page *timens_page = find_timens_vvar_page(vma);
|
|
unsigned long pfn;
|
|
|
|
switch (vmf->pgoff) {
|
|
case VVAR_DATA_PAGE_OFFSET:
|
|
if (timens_page)
|
|
pfn = page_to_pfn(timens_page);
|
|
else
|
|
pfn = sym_to_pfn(vdso_data);
|
|
break;
|
|
#ifdef CONFIG_TIME_NS
|
|
case VVAR_TIMENS_PAGE_OFFSET:
|
|
/*
|
|
* If a task belongs to a time namespace then a namespace
|
|
* specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
|
|
* the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
|
|
* offset.
|
|
* See also the comment near timens_setup_vdso_data().
|
|
*/
|
|
if (!timens_page)
|
|
return VM_FAULT_SIGBUS;
|
|
pfn = sym_to_pfn(vdso_data);
|
|
break;
|
|
#endif /* CONFIG_TIME_NS */
|
|
default:
|
|
return VM_FAULT_SIGBUS;
|
|
}
|
|
|
|
return vmf_insert_pfn(vma, vmf->address, pfn);
|
|
}
|
|
|
|
static int __setup_additional_pages(enum vdso_abi abi,
|
|
struct mm_struct *mm,
|
|
struct linux_binprm *bprm,
|
|
int uses_interp)
|
|
{
|
|
unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
|
|
unsigned long gp_flags = 0;
|
|
void *ret;
|
|
|
|
BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
|
|
|
|
vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
|
|
/* Be sure to map the data page */
|
|
vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE;
|
|
|
|
vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);
|
|
if (IS_ERR_VALUE(vdso_base)) {
|
|
ret = ERR_PTR(vdso_base);
|
|
goto up_fail;
|
|
}
|
|
|
|
ret = _install_special_mapping(mm, vdso_base, VVAR_NR_PAGES * PAGE_SIZE,
|
|
VM_READ|VM_MAYREAD|VM_PFNMAP,
|
|
vdso_info[abi].dm);
|
|
if (IS_ERR(ret))
|
|
goto up_fail;
|
|
|
|
if (IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) && system_supports_bti())
|
|
gp_flags = VM_ARM64_BTI;
|
|
|
|
vdso_base += VVAR_NR_PAGES * PAGE_SIZE;
|
|
mm->context.vdso = (void *)vdso_base;
|
|
ret = _install_special_mapping(mm, vdso_base, vdso_text_len,
|
|
VM_READ|VM_EXEC|gp_flags|
|
|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
|
|
vdso_info[abi].cm);
|
|
if (IS_ERR(ret))
|
|
goto up_fail;
|
|
|
|
return 0;
|
|
|
|
up_fail:
|
|
mm->context.vdso = NULL;
|
|
return PTR_ERR(ret);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
/*
|
|
* Create and map the vectors page for AArch32 tasks.
|
|
*/
|
|
enum aarch32_map {
|
|
AA32_MAP_VECTORS, /* kuser helpers */
|
|
AA32_MAP_SIGPAGE,
|
|
AA32_MAP_VVAR,
|
|
AA32_MAP_VDSO,
|
|
};
|
|
|
|
static struct page *aarch32_vectors_page __ro_after_init;
|
|
static struct page *aarch32_sig_page __ro_after_init;
|
|
|
|
static int aarch32_sigpage_mremap(const struct vm_special_mapping *sm,
|
|
struct vm_area_struct *new_vma)
|
|
{
|
|
current->mm->context.sigpage = (void *)new_vma->vm_start;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct vm_special_mapping aarch32_vdso_maps[] = {
|
|
[AA32_MAP_VECTORS] = {
|
|
.name = "[vectors]", /* ABI */
|
|
.pages = &aarch32_vectors_page,
|
|
},
|
|
[AA32_MAP_SIGPAGE] = {
|
|
.name = "[sigpage]", /* ABI */
|
|
.pages = &aarch32_sig_page,
|
|
.mremap = aarch32_sigpage_mremap,
|
|
},
|
|
[AA32_MAP_VVAR] = {
|
|
.name = "[vvar]",
|
|
.fault = vvar_fault,
|
|
},
|
|
[AA32_MAP_VDSO] = {
|
|
.name = "[vdso]",
|
|
.mremap = vdso_mremap,
|
|
},
|
|
};
|
|
|
|
static int aarch32_alloc_kuser_vdso_page(void)
|
|
{
|
|
extern char __kuser_helper_start[], __kuser_helper_end[];
|
|
int kuser_sz = __kuser_helper_end - __kuser_helper_start;
|
|
unsigned long vdso_page;
|
|
|
|
if (!IS_ENABLED(CONFIG_KUSER_HELPERS))
|
|
return 0;
|
|
|
|
vdso_page = get_zeroed_page(GFP_KERNEL);
|
|
if (!vdso_page)
|
|
return -ENOMEM;
|
|
|
|
memcpy((void *)(vdso_page + 0x1000 - kuser_sz), __kuser_helper_start,
|
|
kuser_sz);
|
|
aarch32_vectors_page = virt_to_page(vdso_page);
|
|
return 0;
|
|
}
|
|
|
|
#define COMPAT_SIGPAGE_POISON_WORD 0xe7fddef1
|
|
static int aarch32_alloc_sigpage(void)
|
|
{
|
|
extern char __aarch32_sigret_code_start[], __aarch32_sigret_code_end[];
|
|
int sigret_sz = __aarch32_sigret_code_end - __aarch32_sigret_code_start;
|
|
__le32 poison = cpu_to_le32(COMPAT_SIGPAGE_POISON_WORD);
|
|
void *sigpage;
|
|
|
|
sigpage = (void *)__get_free_page(GFP_KERNEL);
|
|
if (!sigpage)
|
|
return -ENOMEM;
|
|
|
|
memset32(sigpage, (__force u32)poison, PAGE_SIZE / sizeof(poison));
|
|
memcpy(sigpage, __aarch32_sigret_code_start, sigret_sz);
|
|
aarch32_sig_page = virt_to_page(sigpage);
|
|
return 0;
|
|
}
|
|
|
|
static int __init __aarch32_alloc_vdso_pages(void)
|
|
{
|
|
|
|
if (!IS_ENABLED(CONFIG_COMPAT_VDSO))
|
|
return 0;
|
|
|
|
vdso_info[VDSO_ABI_AA32].dm = &aarch32_vdso_maps[AA32_MAP_VVAR];
|
|
vdso_info[VDSO_ABI_AA32].cm = &aarch32_vdso_maps[AA32_MAP_VDSO];
|
|
|
|
return __vdso_init(VDSO_ABI_AA32);
|
|
}
|
|
|
|
static int __init aarch32_alloc_vdso_pages(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = __aarch32_alloc_vdso_pages();
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = aarch32_alloc_sigpage();
|
|
if (ret)
|
|
return ret;
|
|
|
|
return aarch32_alloc_kuser_vdso_page();
|
|
}
|
|
arch_initcall(aarch32_alloc_vdso_pages);
|
|
|
|
static int aarch32_kuser_helpers_setup(struct mm_struct *mm)
|
|
{
|
|
void *ret;
|
|
|
|
if (!IS_ENABLED(CONFIG_KUSER_HELPERS))
|
|
return 0;
|
|
|
|
/*
|
|
* Avoid VM_MAYWRITE for compatibility with arch/arm/, where it's
|
|
* not safe to CoW the page containing the CPU exception vectors.
|
|
*/
|
|
ret = _install_special_mapping(mm, AARCH32_VECTORS_BASE, PAGE_SIZE,
|
|
VM_READ | VM_EXEC |
|
|
VM_MAYREAD | VM_MAYEXEC,
|
|
&aarch32_vdso_maps[AA32_MAP_VECTORS]);
|
|
|
|
return PTR_ERR_OR_ZERO(ret);
|
|
}
|
|
|
|
static int aarch32_sigreturn_setup(struct mm_struct *mm)
|
|
{
|
|
unsigned long addr;
|
|
void *ret;
|
|
|
|
addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
|
|
if (IS_ERR_VALUE(addr)) {
|
|
ret = ERR_PTR(addr);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* VM_MAYWRITE is required to allow gdb to Copy-on-Write and
|
|
* set breakpoints.
|
|
*/
|
|
ret = _install_special_mapping(mm, addr, PAGE_SIZE,
|
|
VM_READ | VM_EXEC | VM_MAYREAD |
|
|
VM_MAYWRITE | VM_MAYEXEC,
|
|
&aarch32_vdso_maps[AA32_MAP_SIGPAGE]);
|
|
if (IS_ERR(ret))
|
|
goto out;
|
|
|
|
mm->context.sigpage = (void *)addr;
|
|
|
|
out:
|
|
return PTR_ERR_OR_ZERO(ret);
|
|
}
|
|
|
|
int aarch32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
int ret;
|
|
|
|
if (mmap_write_lock_killable(mm))
|
|
return -EINTR;
|
|
|
|
ret = aarch32_kuser_helpers_setup(mm);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if (IS_ENABLED(CONFIG_COMPAT_VDSO)) {
|
|
ret = __setup_additional_pages(VDSO_ABI_AA32, mm, bprm,
|
|
uses_interp);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
ret = aarch32_sigreturn_setup(mm);
|
|
out:
|
|
mmap_write_unlock(mm);
|
|
return ret;
|
|
}
|
|
#endif /* CONFIG_COMPAT */
|
|
|
|
enum aarch64_map {
|
|
AA64_MAP_VVAR,
|
|
AA64_MAP_VDSO,
|
|
};
|
|
|
|
static struct vm_special_mapping aarch64_vdso_maps[] __ro_after_init = {
|
|
[AA64_MAP_VVAR] = {
|
|
.name = "[vvar]",
|
|
.fault = vvar_fault,
|
|
},
|
|
[AA64_MAP_VDSO] = {
|
|
.name = "[vdso]",
|
|
.mremap = vdso_mremap,
|
|
},
|
|
};
|
|
|
|
static int __init vdso_init(void)
|
|
{
|
|
vdso_info[VDSO_ABI_AA64].dm = &aarch64_vdso_maps[AA64_MAP_VVAR];
|
|
vdso_info[VDSO_ABI_AA64].cm = &aarch64_vdso_maps[AA64_MAP_VDSO];
|
|
|
|
return __vdso_init(VDSO_ABI_AA64);
|
|
}
|
|
arch_initcall(vdso_init);
|
|
|
|
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
int ret;
|
|
|
|
if (mmap_write_lock_killable(mm))
|
|
return -EINTR;
|
|
|
|
ret = __setup_additional_pages(VDSO_ABI_AA64, mm, bprm, uses_interp);
|
|
mmap_write_unlock(mm);
|
|
|
|
return ret;
|
|
}
|