1caab277bSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 29031fefdSWill Deacon /* 30d747f65SVincenzo Frascino * VDSO implementations. 49031fefdSWill Deacon * 59031fefdSWill Deacon * Copyright (C) 2012 ARM Limited 69031fefdSWill Deacon * 79031fefdSWill Deacon * Author: Will Deacon <will.deacon@arm.com> 89031fefdSWill Deacon */ 99031fefdSWill Deacon 105a9e3e15SJisheng Zhang #include <linux/cache.h> 119031fefdSWill Deacon #include <linux/clocksource.h> 129031fefdSWill Deacon #include <linux/elf.h> 139031fefdSWill Deacon #include <linux/err.h> 149031fefdSWill Deacon #include <linux/errno.h> 159031fefdSWill Deacon #include <linux/gfp.h> 165a9e3e15SJisheng Zhang #include <linux/kernel.h> 179031fefdSWill Deacon #include <linux/mm.h> 189031fefdSWill Deacon #include <linux/sched.h> 199031fefdSWill Deacon #include <linux/signal.h> 209031fefdSWill Deacon #include <linux/slab.h> 21c60b0c28SCatalin Marinas #include <linux/timekeeper_internal.h> 229031fefdSWill Deacon #include <linux/vmalloc.h> 2328b1a824SVincenzo Frascino #include <vdso/datapage.h> 2428b1a824SVincenzo Frascino #include <vdso/helpers.h> 2528b1a824SVincenzo Frascino #include <vdso/vsyscall.h> 269031fefdSWill Deacon 279031fefdSWill Deacon #include <asm/cacheflush.h> 289031fefdSWill Deacon #include <asm/signal32.h> 299031fefdSWill Deacon #include <asm/vdso.h> 309031fefdSWill Deacon 31dbbb08f5SKees Cook extern char vdso_start[], vdso_end[]; 327c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 337c1deeebSVincenzo Frascino extern char vdso32_start[], vdso32_end[]; 347c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 35c7aa2d71SVincenzo Frascino 36d3418f38SMark Rutland enum vdso_abi { 37d3418f38SMark Rutland VDSO_ABI_AA64, 387c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 39d3418f38SMark Rutland VDSO_ABI_AA32, 407c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 41c7aa2d71SVincenzo Frascino }; 42c7aa2d71SVincenzo Frascino 433503d56cSAndrei Vagin enum vvar_pages { 443503d56cSAndrei Vagin VVAR_DATA_PAGE_OFFSET, 453503d56cSAndrei Vagin VVAR_TIMENS_PAGE_OFFSET, 463503d56cSAndrei Vagin VVAR_NR_PAGES, 473503d56cSAndrei Vagin }; 483503d56cSAndrei Vagin 49d3418f38SMark Rutland struct vdso_abi_info { 50c7aa2d71SVincenzo Frascino const char *name; 51c7aa2d71SVincenzo Frascino const char *vdso_code_start; 52c7aa2d71SVincenzo Frascino const char *vdso_code_end; 53c7aa2d71SVincenzo Frascino unsigned long vdso_pages; 54c7aa2d71SVincenzo Frascino /* Data Mapping */ 55c7aa2d71SVincenzo Frascino struct vm_special_mapping *dm; 56c7aa2d71SVincenzo Frascino /* Code Mapping */ 57c7aa2d71SVincenzo Frascino struct vm_special_mapping *cm; 58c7aa2d71SVincenzo Frascino }; 59c7aa2d71SVincenzo Frascino 60d3418f38SMark Rutland static struct vdso_abi_info vdso_info[] __ro_after_init = { 61d3418f38SMark Rutland [VDSO_ABI_AA64] = { 62c7aa2d71SVincenzo Frascino .name = "vdso", 63c7aa2d71SVincenzo Frascino .vdso_code_start = vdso_start, 64c7aa2d71SVincenzo Frascino .vdso_code_end = vdso_end, 65c7aa2d71SVincenzo Frascino }, 667c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 67d3418f38SMark Rutland [VDSO_ABI_AA32] = { 687c1deeebSVincenzo Frascino .name = "vdso32", 697c1deeebSVincenzo Frascino .vdso_code_start = vdso32_start, 707c1deeebSVincenzo Frascino .vdso_code_end = vdso32_end, 717c1deeebSVincenzo Frascino }, 727c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 73c7aa2d71SVincenzo Frascino }; 749031fefdSWill Deacon 759031fefdSWill Deacon /* 769031fefdSWill Deacon * The vDSO data page. 779031fefdSWill Deacon */ 789031fefdSWill Deacon static union { 7928b1a824SVincenzo Frascino struct vdso_data data[CS_BASES]; 809031fefdSWill Deacon u8 page[PAGE_SIZE]; 819031fefdSWill Deacon } vdso_data_store __page_aligned_data; 8228b1a824SVincenzo Frascino struct vdso_data *vdso_data = vdso_data_store.data; 839031fefdSWill Deacon 84d3418f38SMark Rutland static int __vdso_remap(enum vdso_abi abi, 85c7aa2d71SVincenzo Frascino const struct vm_special_mapping *sm, 86c7aa2d71SVincenzo Frascino struct vm_area_struct *new_vma) 87c7aa2d71SVincenzo Frascino { 88c7aa2d71SVincenzo Frascino unsigned long new_size = new_vma->vm_end - new_vma->vm_start; 89d3418f38SMark Rutland unsigned long vdso_size = vdso_info[abi].vdso_code_end - 90d3418f38SMark Rutland vdso_info[abi].vdso_code_start; 91c7aa2d71SVincenzo Frascino 92c7aa2d71SVincenzo Frascino if (vdso_size != new_size) 93c7aa2d71SVincenzo Frascino return -EINVAL; 94c7aa2d71SVincenzo Frascino 95c7aa2d71SVincenzo Frascino current->mm->context.vdso = (void *)new_vma->vm_start; 96c7aa2d71SVincenzo Frascino 97c7aa2d71SVincenzo Frascino return 0; 98c7aa2d71SVincenzo Frascino } 99c7aa2d71SVincenzo Frascino 100d3418f38SMark Rutland static int __vdso_init(enum vdso_abi abi) 101c7aa2d71SVincenzo Frascino { 102c7aa2d71SVincenzo Frascino int i; 103c7aa2d71SVincenzo Frascino struct page **vdso_pagelist; 104c7aa2d71SVincenzo Frascino unsigned long pfn; 105c7aa2d71SVincenzo Frascino 106d3418f38SMark Rutland if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4)) { 107c7aa2d71SVincenzo Frascino pr_err("vDSO is not a valid ELF object!\n"); 108c7aa2d71SVincenzo Frascino return -EINVAL; 109c7aa2d71SVincenzo Frascino } 110c7aa2d71SVincenzo Frascino 111d3418f38SMark Rutland vdso_info[abi].vdso_pages = ( 112d3418f38SMark Rutland vdso_info[abi].vdso_code_end - 113d3418f38SMark Rutland vdso_info[abi].vdso_code_start) >> 114c7aa2d71SVincenzo Frascino PAGE_SHIFT; 115c7aa2d71SVincenzo Frascino 116d53b5c01SAndrei Vagin vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages, 117c7aa2d71SVincenzo Frascino sizeof(struct page *), 118c7aa2d71SVincenzo Frascino GFP_KERNEL); 119c7aa2d71SVincenzo Frascino if (vdso_pagelist == NULL) 120c7aa2d71SVincenzo Frascino return -ENOMEM; 121c7aa2d71SVincenzo Frascino 122c7aa2d71SVincenzo Frascino /* Grab the vDSO code pages. */ 123d3418f38SMark Rutland pfn = sym_to_pfn(vdso_info[abi].vdso_code_start); 124c7aa2d71SVincenzo Frascino 125d3418f38SMark Rutland for (i = 0; i < vdso_info[abi].vdso_pages; i++) 126d53b5c01SAndrei Vagin vdso_pagelist[i] = pfn_to_page(pfn + i); 127c7aa2d71SVincenzo Frascino 128d53b5c01SAndrei Vagin vdso_info[abi].cm->pages = vdso_pagelist; 129c7aa2d71SVincenzo Frascino 130c7aa2d71SVincenzo Frascino return 0; 131c7aa2d71SVincenzo Frascino } 132c7aa2d71SVincenzo Frascino 1331b6867d2SAndrei Vagin #ifdef CONFIG_TIME_NS 1343503d56cSAndrei Vagin struct vdso_data *arch_get_vdso_data(void *vvar_page) 1353503d56cSAndrei Vagin { 1363503d56cSAndrei Vagin return (struct vdso_data *)(vvar_page); 1373503d56cSAndrei Vagin } 1383503d56cSAndrei Vagin 1391b6867d2SAndrei Vagin /* 1401b6867d2SAndrei Vagin * The vvar mapping contains data for a specific time namespace, so when a task 1411b6867d2SAndrei Vagin * changes namespace we must unmap its vvar data for the old namespace. 1421b6867d2SAndrei Vagin * Subsequent faults will map in data for the new namespace. 1431b6867d2SAndrei Vagin * 1441b6867d2SAndrei Vagin * For more details see timens_setup_vdso_data(). 1451b6867d2SAndrei Vagin */ 1461b6867d2SAndrei Vagin int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) 1471b6867d2SAndrei Vagin { 1481b6867d2SAndrei Vagin struct mm_struct *mm = task->mm; 1491b6867d2SAndrei Vagin struct vm_area_struct *vma; 1501b6867d2SAndrei Vagin 1511b6867d2SAndrei Vagin mmap_read_lock(mm); 1521b6867d2SAndrei Vagin 1531b6867d2SAndrei Vagin for (vma = mm->mmap; vma; vma = vma->vm_next) { 1541b6867d2SAndrei Vagin unsigned long size = vma->vm_end - vma->vm_start; 1551b6867d2SAndrei Vagin 1561b6867d2SAndrei Vagin if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA64].dm)) 1571b6867d2SAndrei Vagin zap_page_range(vma, vma->vm_start, size); 1581b6867d2SAndrei Vagin #ifdef CONFIG_COMPAT_VDSO 1591b6867d2SAndrei Vagin if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA32].dm)) 1601b6867d2SAndrei Vagin zap_page_range(vma, vma->vm_start, size); 1611b6867d2SAndrei Vagin #endif 1621b6867d2SAndrei Vagin } 1631b6867d2SAndrei Vagin 1641b6867d2SAndrei Vagin mmap_read_unlock(mm); 1651b6867d2SAndrei Vagin return 0; 1661b6867d2SAndrei Vagin } 1671b6867d2SAndrei Vagin #endif 1681b6867d2SAndrei Vagin 169d53b5c01SAndrei Vagin static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, 170d53b5c01SAndrei Vagin struct vm_area_struct *vma, struct vm_fault *vmf) 171d53b5c01SAndrei Vagin { 172d53b5c01SAndrei Vagin if (vmf->pgoff == 0) 173d53b5c01SAndrei Vagin return vmf_insert_pfn(vma, vmf->address, 174d53b5c01SAndrei Vagin sym_to_pfn(vdso_data)); 175d53b5c01SAndrei Vagin return VM_FAULT_SIGBUS; 176d53b5c01SAndrei Vagin } 177d53b5c01SAndrei Vagin 178d3418f38SMark Rutland static int __setup_additional_pages(enum vdso_abi abi, 179c7aa2d71SVincenzo Frascino struct mm_struct *mm, 180c7aa2d71SVincenzo Frascino struct linux_binprm *bprm, 181c7aa2d71SVincenzo Frascino int uses_interp) 182c7aa2d71SVincenzo Frascino { 183c7aa2d71SVincenzo Frascino unsigned long vdso_base, vdso_text_len, vdso_mapping_len; 184bf740a90SMark Brown unsigned long gp_flags = 0; 185c7aa2d71SVincenzo Frascino void *ret; 186c7aa2d71SVincenzo Frascino 1873503d56cSAndrei Vagin BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES); 1883503d56cSAndrei Vagin 189d3418f38SMark Rutland vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT; 190c7aa2d71SVincenzo Frascino /* Be sure to map the data page */ 1913503d56cSAndrei Vagin vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE; 192c7aa2d71SVincenzo Frascino 193c7aa2d71SVincenzo Frascino vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0); 194c7aa2d71SVincenzo Frascino if (IS_ERR_VALUE(vdso_base)) { 195c7aa2d71SVincenzo Frascino ret = ERR_PTR(vdso_base); 196c7aa2d71SVincenzo Frascino goto up_fail; 197c7aa2d71SVincenzo Frascino } 198c7aa2d71SVincenzo Frascino 1993503d56cSAndrei Vagin ret = _install_special_mapping(mm, vdso_base, VVAR_NR_PAGES * PAGE_SIZE, 200d53b5c01SAndrei Vagin VM_READ|VM_MAYREAD|VM_PFNMAP, 201d3418f38SMark Rutland vdso_info[abi].dm); 202c7aa2d71SVincenzo Frascino if (IS_ERR(ret)) 203c7aa2d71SVincenzo Frascino goto up_fail; 204c7aa2d71SVincenzo Frascino 205bf740a90SMark Brown if (IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) && system_supports_bti()) 206bf740a90SMark Brown gp_flags = VM_ARM64_BTI; 207bf740a90SMark Brown 2083503d56cSAndrei Vagin vdso_base += VVAR_NR_PAGES * PAGE_SIZE; 209c7aa2d71SVincenzo Frascino mm->context.vdso = (void *)vdso_base; 210c7aa2d71SVincenzo Frascino ret = _install_special_mapping(mm, vdso_base, vdso_text_len, 211bf740a90SMark Brown VM_READ|VM_EXEC|gp_flags| 212c7aa2d71SVincenzo Frascino VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 213d3418f38SMark Rutland vdso_info[abi].cm); 214c7aa2d71SVincenzo Frascino if (IS_ERR(ret)) 215c7aa2d71SVincenzo Frascino goto up_fail; 216c7aa2d71SVincenzo Frascino 217c7aa2d71SVincenzo Frascino return 0; 218c7aa2d71SVincenzo Frascino 219c7aa2d71SVincenzo Frascino up_fail: 220c7aa2d71SVincenzo Frascino mm->context.vdso = NULL; 221c7aa2d71SVincenzo Frascino return PTR_ERR(ret); 222c7aa2d71SVincenzo Frascino } 223c7aa2d71SVincenzo Frascino 2249031fefdSWill Deacon #ifdef CONFIG_COMPAT 2259031fefdSWill Deacon /* 2269031fefdSWill Deacon * Create and map the vectors page for AArch32 tasks. 2279031fefdSWill Deacon */ 2287c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 2297c1deeebSVincenzo Frascino static int aarch32_vdso_mremap(const struct vm_special_mapping *sm, 2307c1deeebSVincenzo Frascino struct vm_area_struct *new_vma) 2317c1deeebSVincenzo Frascino { 232d3418f38SMark Rutland return __vdso_remap(VDSO_ABI_AA32, sm, new_vma); 2337c1deeebSVincenzo Frascino } 2347c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 2357c1deeebSVincenzo Frascino 2361d09094aSMark Rutland enum aarch32_map { 2371d09094aSMark Rutland AA32_MAP_VECTORS, /* kuser helpers */ 2387c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 2391d09094aSMark Rutland AA32_MAP_VVAR, 2401d09094aSMark Rutland AA32_MAP_VDSO, 2411d09094aSMark Rutland #endif 242a39060b0SWill Deacon AA32_MAP_SIGPAGE 2431d09094aSMark Rutland }; 24474fc72e7SMark Rutland 24574fc72e7SMark Rutland static struct page *aarch32_vectors_page __ro_after_init; 24674fc72e7SMark Rutland static struct page *aarch32_sig_page __ro_after_init; 24774fc72e7SMark Rutland 2481d09094aSMark Rutland static struct vm_special_mapping aarch32_vdso_maps[] = { 2491d09094aSMark Rutland [AA32_MAP_VECTORS] = { 2500d747f65SVincenzo Frascino .name = "[vectors]", /* ABI */ 25174fc72e7SMark Rutland .pages = &aarch32_vectors_page, 2520d747f65SVincenzo Frascino }, 2537c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 2541d09094aSMark Rutland [AA32_MAP_VVAR] = { 2557c1deeebSVincenzo Frascino .name = "[vvar]", 256d53b5c01SAndrei Vagin .fault = vvar_fault, 2577c1deeebSVincenzo Frascino }, 2581d09094aSMark Rutland [AA32_MAP_VDSO] = { 2597c1deeebSVincenzo Frascino .name = "[vdso]", 2607c1deeebSVincenzo Frascino .mremap = aarch32_vdso_mremap, 2617c1deeebSVincenzo Frascino }, 262a39060b0SWill Deacon #endif /* CONFIG_COMPAT_VDSO */ 2631d09094aSMark Rutland [AA32_MAP_SIGPAGE] = { 2640d747f65SVincenzo Frascino .name = "[sigpage]", /* ABI */ 26574fc72e7SMark Rutland .pages = &aarch32_sig_page, 2660d747f65SVincenzo Frascino }, 2670d747f65SVincenzo Frascino }; 2689031fefdSWill Deacon 2691255a734SVincenzo Frascino static int aarch32_alloc_kuser_vdso_page(void) 2709031fefdSWill Deacon { 2719031fefdSWill Deacon extern char __kuser_helper_start[], __kuser_helper_end[]; 2729031fefdSWill Deacon int kuser_sz = __kuser_helper_end - __kuser_helper_start; 2731255a734SVincenzo Frascino unsigned long vdso_page; 2749031fefdSWill Deacon 275af1b3cf2SVincenzo Frascino if (!IS_ENABLED(CONFIG_KUSER_HELPERS)) 276af1b3cf2SVincenzo Frascino return 0; 277af1b3cf2SVincenzo Frascino 2781255a734SVincenzo Frascino vdso_page = get_zeroed_page(GFP_ATOMIC); 2791255a734SVincenzo Frascino if (!vdso_page) 2809031fefdSWill Deacon return -ENOMEM; 2819031fefdSWill Deacon 2821255a734SVincenzo Frascino memcpy((void *)(vdso_page + 0x1000 - kuser_sz), __kuser_helper_start, 2831255a734SVincenzo Frascino kuser_sz); 28474fc72e7SMark Rutland aarch32_vectors_page = virt_to_page(vdso_page); 28574fc72e7SMark Rutland flush_dcache_page(aarch32_vectors_page); 2861255a734SVincenzo Frascino return 0; 2870d747f65SVincenzo Frascino } 2880d747f65SVincenzo Frascino 289a39060b0SWill Deacon static int aarch32_alloc_sigpage(void) 2901255a734SVincenzo Frascino { 2911255a734SVincenzo Frascino extern char __aarch32_sigret_code_start[], __aarch32_sigret_code_end[]; 2921255a734SVincenzo Frascino int sigret_sz = __aarch32_sigret_code_end - __aarch32_sigret_code_start; 2931255a734SVincenzo Frascino unsigned long sigpage; 2949031fefdSWill Deacon 2951255a734SVincenzo Frascino sigpage = get_zeroed_page(GFP_ATOMIC); 2961255a734SVincenzo Frascino if (!sigpage) 2971255a734SVincenzo Frascino return -ENOMEM; 2989031fefdSWill Deacon 2991255a734SVincenzo Frascino memcpy((void *)sigpage, __aarch32_sigret_code_start, sigret_sz); 30074fc72e7SMark Rutland aarch32_sig_page = virt_to_page(sigpage); 30174fc72e7SMark Rutland flush_dcache_page(aarch32_sig_page); 302a39060b0SWill Deacon return 0; 303a39060b0SWill Deacon } 3040d747f65SVincenzo Frascino 305a39060b0SWill Deacon #ifdef CONFIG_COMPAT_VDSO 306a39060b0SWill Deacon static int __aarch32_alloc_vdso_pages(void) 307a39060b0SWill Deacon { 308a39060b0SWill Deacon vdso_info[VDSO_ABI_AA32].dm = &aarch32_vdso_maps[AA32_MAP_VVAR]; 309a39060b0SWill Deacon vdso_info[VDSO_ABI_AA32].cm = &aarch32_vdso_maps[AA32_MAP_VDSO]; 3109031fefdSWill Deacon 311a39060b0SWill Deacon return __vdso_init(VDSO_ABI_AA32); 3129031fefdSWill Deacon } 3137c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 3147c1deeebSVincenzo Frascino 3157c1deeebSVincenzo Frascino static int __init aarch32_alloc_vdso_pages(void) 3167c1deeebSVincenzo Frascino { 317a39060b0SWill Deacon int ret; 318a39060b0SWill Deacon 319a39060b0SWill Deacon #ifdef CONFIG_COMPAT_VDSO 320a39060b0SWill Deacon ret = __aarch32_alloc_vdso_pages(); 321a39060b0SWill Deacon if (ret) 322a39060b0SWill Deacon return ret; 323a39060b0SWill Deacon #endif 324a39060b0SWill Deacon 325a39060b0SWill Deacon ret = aarch32_alloc_sigpage(); 326a39060b0SWill Deacon if (ret) 327a39060b0SWill Deacon return ret; 328a39060b0SWill Deacon 329a39060b0SWill Deacon return aarch32_alloc_kuser_vdso_page(); 3307c1deeebSVincenzo Frascino } 3310d747f65SVincenzo Frascino arch_initcall(aarch32_alloc_vdso_pages); 3329031fefdSWill Deacon 3330d747f65SVincenzo Frascino static int aarch32_kuser_helpers_setup(struct mm_struct *mm) 3340d747f65SVincenzo Frascino { 3350d747f65SVincenzo Frascino void *ret; 3360d747f65SVincenzo Frascino 337af1b3cf2SVincenzo Frascino if (!IS_ENABLED(CONFIG_KUSER_HELPERS)) 338af1b3cf2SVincenzo Frascino return 0; 339af1b3cf2SVincenzo Frascino 3400d747f65SVincenzo Frascino /* 3410d747f65SVincenzo Frascino * Avoid VM_MAYWRITE for compatibility with arch/arm/, where it's 3420d747f65SVincenzo Frascino * not safe to CoW the page containing the CPU exception vectors. 3430d747f65SVincenzo Frascino */ 3440d747f65SVincenzo Frascino ret = _install_special_mapping(mm, AARCH32_VECTORS_BASE, PAGE_SIZE, 3450d747f65SVincenzo Frascino VM_READ | VM_EXEC | 3460d747f65SVincenzo Frascino VM_MAYREAD | VM_MAYEXEC, 3471d09094aSMark Rutland &aarch32_vdso_maps[AA32_MAP_VECTORS]); 3480d747f65SVincenzo Frascino 3490d747f65SVincenzo Frascino return PTR_ERR_OR_ZERO(ret); 3500d747f65SVincenzo Frascino } 3510d747f65SVincenzo Frascino 3520d747f65SVincenzo Frascino static int aarch32_sigreturn_setup(struct mm_struct *mm) 3530d747f65SVincenzo Frascino { 3540d747f65SVincenzo Frascino unsigned long addr; 3550d747f65SVincenzo Frascino void *ret; 3560d747f65SVincenzo Frascino 3570d747f65SVincenzo Frascino addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0); 3580d747f65SVincenzo Frascino if (IS_ERR_VALUE(addr)) { 3590d747f65SVincenzo Frascino ret = ERR_PTR(addr); 3600d747f65SVincenzo Frascino goto out; 3610d747f65SVincenzo Frascino } 3620d747f65SVincenzo Frascino 3630d747f65SVincenzo Frascino /* 3640d747f65SVincenzo Frascino * VM_MAYWRITE is required to allow gdb to Copy-on-Write and 3650d747f65SVincenzo Frascino * set breakpoints. 3660d747f65SVincenzo Frascino */ 3670d747f65SVincenzo Frascino ret = _install_special_mapping(mm, addr, PAGE_SIZE, 3680d747f65SVincenzo Frascino VM_READ | VM_EXEC | VM_MAYREAD | 3690d747f65SVincenzo Frascino VM_MAYWRITE | VM_MAYEXEC, 3701d09094aSMark Rutland &aarch32_vdso_maps[AA32_MAP_SIGPAGE]); 3710d747f65SVincenzo Frascino if (IS_ERR(ret)) 3720d747f65SVincenzo Frascino goto out; 3730d747f65SVincenzo Frascino 374a39060b0SWill Deacon mm->context.sigpage = (void *)addr; 3750d747f65SVincenzo Frascino 3760d747f65SVincenzo Frascino out: 3770d747f65SVincenzo Frascino return PTR_ERR_OR_ZERO(ret); 3780d747f65SVincenzo Frascino } 3790d747f65SVincenzo Frascino 3800d747f65SVincenzo Frascino int aarch32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 3819031fefdSWill Deacon { 3829031fefdSWill Deacon struct mm_struct *mm = current->mm; 3830d747f65SVincenzo Frascino int ret; 3849031fefdSWill Deacon 385d8ed45c5SMichel Lespinasse if (mmap_write_lock_killable(mm)) 38669048176SMichal Hocko return -EINTR; 3879031fefdSWill Deacon 3880d747f65SVincenzo Frascino ret = aarch32_kuser_helpers_setup(mm); 3890d747f65SVincenzo Frascino if (ret) 3900d747f65SVincenzo Frascino goto out; 3919031fefdSWill Deacon 3927c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 393d3418f38SMark Rutland ret = __setup_additional_pages(VDSO_ABI_AA32, 3947c1deeebSVincenzo Frascino mm, 3957c1deeebSVincenzo Frascino bprm, 3967c1deeebSVincenzo Frascino uses_interp); 397a39060b0SWill Deacon if (ret) 398a39060b0SWill Deacon goto out; 3997c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 4000d747f65SVincenzo Frascino 401a39060b0SWill Deacon ret = aarch32_sigreturn_setup(mm); 4020d747f65SVincenzo Frascino out: 403d8ed45c5SMichel Lespinasse mmap_write_unlock(mm); 4040d747f65SVincenzo Frascino return ret; 4059031fefdSWill Deacon } 4069031fefdSWill Deacon #endif /* CONFIG_COMPAT */ 4079031fefdSWill Deacon 40873958695SDmitry Safonov static int vdso_mremap(const struct vm_special_mapping *sm, 40973958695SDmitry Safonov struct vm_area_struct *new_vma) 41073958695SDmitry Safonov { 411d3418f38SMark Rutland return __vdso_remap(VDSO_ABI_AA64, sm, new_vma); 41273958695SDmitry Safonov } 41373958695SDmitry Safonov 4141d09094aSMark Rutland enum aarch64_map { 4151d09094aSMark Rutland AA64_MAP_VVAR, 4161d09094aSMark Rutland AA64_MAP_VDSO, 4171d09094aSMark Rutland }; 4181d09094aSMark Rutland 4191d09094aSMark Rutland static struct vm_special_mapping aarch64_vdso_maps[] __ro_after_init = { 4201d09094aSMark Rutland [AA64_MAP_VVAR] = { 4215a9e3e15SJisheng Zhang .name = "[vvar]", 422d53b5c01SAndrei Vagin .fault = vvar_fault, 4235a9e3e15SJisheng Zhang }, 4241d09094aSMark Rutland [AA64_MAP_VDSO] = { 4255a9e3e15SJisheng Zhang .name = "[vdso]", 42673958695SDmitry Safonov .mremap = vdso_mremap, 4275a9e3e15SJisheng Zhang }, 4285a9e3e15SJisheng Zhang }; 4292fea7f6cSWill Deacon 4309031fefdSWill Deacon static int __init vdso_init(void) 4319031fefdSWill Deacon { 4321d09094aSMark Rutland vdso_info[VDSO_ABI_AA64].dm = &aarch64_vdso_maps[AA64_MAP_VVAR]; 4331d09094aSMark Rutland vdso_info[VDSO_ABI_AA64].cm = &aarch64_vdso_maps[AA64_MAP_VDSO]; 43416fb1a9bSNathan Lynch 435d3418f38SMark Rutland return __vdso_init(VDSO_ABI_AA64); 4369031fefdSWill Deacon } 4379031fefdSWill Deacon arch_initcall(vdso_init); 4389031fefdSWill Deacon 4399031fefdSWill Deacon int arch_setup_additional_pages(struct linux_binprm *bprm, 4409031fefdSWill Deacon int uses_interp) 4419031fefdSWill Deacon { 4429031fefdSWill Deacon struct mm_struct *mm = current->mm; 443c7aa2d71SVincenzo Frascino int ret; 4449031fefdSWill Deacon 445d8ed45c5SMichel Lespinasse if (mmap_write_lock_killable(mm)) 44669048176SMichal Hocko return -EINTR; 44787154938SWill Deacon 448d3418f38SMark Rutland ret = __setup_additional_pages(VDSO_ABI_AA64, 449c7aa2d71SVincenzo Frascino mm, 450c7aa2d71SVincenzo Frascino bprm, 451c7aa2d71SVincenzo Frascino uses_interp); 452601255aeSWill Deacon 453d8ed45c5SMichel Lespinasse mmap_write_unlock(mm); 4549031fefdSWill Deacon 455c7aa2d71SVincenzo Frascino return ret; 4569031fefdSWill Deacon } 457