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> 21ee3cda8eSAndrei Vagin #include <linux/time_namespace.h> 22c60b0c28SCatalin Marinas #include <linux/timekeeper_internal.h> 239031fefdSWill Deacon #include <linux/vmalloc.h> 2428b1a824SVincenzo Frascino #include <vdso/datapage.h> 2528b1a824SVincenzo Frascino #include <vdso/helpers.h> 2628b1a824SVincenzo Frascino #include <vdso/vsyscall.h> 279031fefdSWill Deacon 289031fefdSWill Deacon #include <asm/cacheflush.h> 299031fefdSWill Deacon #include <asm/signal32.h> 309031fefdSWill Deacon #include <asm/vdso.h> 319031fefdSWill Deacon 32dbbb08f5SKees Cook extern char vdso_start[], vdso_end[]; 337c1deeebSVincenzo Frascino extern char vdso32_start[], vdso32_end[]; 34c7aa2d71SVincenzo Frascino 35d3418f38SMark Rutland enum vdso_abi { 36d3418f38SMark Rutland VDSO_ABI_AA64, 37d3418f38SMark Rutland VDSO_ABI_AA32, 38c7aa2d71SVincenzo Frascino }; 39c7aa2d71SVincenzo Frascino 403503d56cSAndrei Vagin enum vvar_pages { 413503d56cSAndrei Vagin VVAR_DATA_PAGE_OFFSET, 423503d56cSAndrei Vagin VVAR_TIMENS_PAGE_OFFSET, 433503d56cSAndrei Vagin VVAR_NR_PAGES, 443503d56cSAndrei Vagin }; 453503d56cSAndrei Vagin 46d3418f38SMark Rutland struct vdso_abi_info { 47c7aa2d71SVincenzo Frascino const char *name; 48c7aa2d71SVincenzo Frascino const char *vdso_code_start; 49c7aa2d71SVincenzo Frascino const char *vdso_code_end; 50c7aa2d71SVincenzo Frascino unsigned long vdso_pages; 51c7aa2d71SVincenzo Frascino /* Data Mapping */ 52c7aa2d71SVincenzo Frascino struct vm_special_mapping *dm; 53c7aa2d71SVincenzo Frascino /* Code Mapping */ 54c7aa2d71SVincenzo Frascino struct vm_special_mapping *cm; 55c7aa2d71SVincenzo Frascino }; 56c7aa2d71SVincenzo Frascino 57d3418f38SMark Rutland static struct vdso_abi_info vdso_info[] __ro_after_init = { 58d3418f38SMark Rutland [VDSO_ABI_AA64] = { 59c7aa2d71SVincenzo Frascino .name = "vdso", 60c7aa2d71SVincenzo Frascino .vdso_code_start = vdso_start, 61c7aa2d71SVincenzo Frascino .vdso_code_end = vdso_end, 62c7aa2d71SVincenzo Frascino }, 637c1deeebSVincenzo Frascino #ifdef CONFIG_COMPAT_VDSO 64d3418f38SMark Rutland [VDSO_ABI_AA32] = { 657c1deeebSVincenzo Frascino .name = "vdso32", 667c1deeebSVincenzo Frascino .vdso_code_start = vdso32_start, 677c1deeebSVincenzo Frascino .vdso_code_end = vdso32_end, 687c1deeebSVincenzo Frascino }, 697c1deeebSVincenzo Frascino #endif /* CONFIG_COMPAT_VDSO */ 70c7aa2d71SVincenzo Frascino }; 719031fefdSWill Deacon 729031fefdSWill Deacon /* 739031fefdSWill Deacon * The vDSO data page. 749031fefdSWill Deacon */ 759031fefdSWill Deacon static union { 7628b1a824SVincenzo Frascino struct vdso_data data[CS_BASES]; 779031fefdSWill Deacon u8 page[PAGE_SIZE]; 789031fefdSWill Deacon } vdso_data_store __page_aligned_data; 7928b1a824SVincenzo Frascino struct vdso_data *vdso_data = vdso_data_store.data; 809031fefdSWill Deacon 81d3418f38SMark Rutland static int __vdso_remap(enum vdso_abi abi, 82c7aa2d71SVincenzo Frascino const struct vm_special_mapping *sm, 83c7aa2d71SVincenzo Frascino struct vm_area_struct *new_vma) 84c7aa2d71SVincenzo Frascino { 85c7aa2d71SVincenzo Frascino unsigned long new_size = new_vma->vm_end - new_vma->vm_start; 86d3418f38SMark Rutland unsigned long vdso_size = vdso_info[abi].vdso_code_end - 87d3418f38SMark Rutland vdso_info[abi].vdso_code_start; 88c7aa2d71SVincenzo Frascino 89c7aa2d71SVincenzo Frascino if (vdso_size != new_size) 90c7aa2d71SVincenzo Frascino return -EINVAL; 91c7aa2d71SVincenzo Frascino 92c7aa2d71SVincenzo Frascino current->mm->context.vdso = (void *)new_vma->vm_start; 93c7aa2d71SVincenzo Frascino 94c7aa2d71SVincenzo Frascino return 0; 95c7aa2d71SVincenzo Frascino } 96c7aa2d71SVincenzo Frascino 97d3418f38SMark Rutland static int __vdso_init(enum vdso_abi abi) 98c7aa2d71SVincenzo Frascino { 99c7aa2d71SVincenzo Frascino int i; 100c7aa2d71SVincenzo Frascino struct page **vdso_pagelist; 101c7aa2d71SVincenzo Frascino unsigned long pfn; 102c7aa2d71SVincenzo Frascino 103d3418f38SMark Rutland if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4)) { 104c7aa2d71SVincenzo Frascino pr_err("vDSO is not a valid ELF object!\n"); 105c7aa2d71SVincenzo Frascino return -EINVAL; 106c7aa2d71SVincenzo Frascino } 107c7aa2d71SVincenzo Frascino 108d3418f38SMark Rutland vdso_info[abi].vdso_pages = ( 109d3418f38SMark Rutland vdso_info[abi].vdso_code_end - 110d3418f38SMark Rutland vdso_info[abi].vdso_code_start) >> 111c7aa2d71SVincenzo Frascino PAGE_SHIFT; 112c7aa2d71SVincenzo Frascino 113d53b5c01SAndrei Vagin vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages, 114c7aa2d71SVincenzo Frascino sizeof(struct page *), 115c7aa2d71SVincenzo Frascino GFP_KERNEL); 116c7aa2d71SVincenzo Frascino if (vdso_pagelist == NULL) 117c7aa2d71SVincenzo Frascino return -ENOMEM; 118c7aa2d71SVincenzo Frascino 119c7aa2d71SVincenzo Frascino /* Grab the vDSO code pages. */ 120d3418f38SMark Rutland pfn = sym_to_pfn(vdso_info[abi].vdso_code_start); 121c7aa2d71SVincenzo Frascino 122d3418f38SMark Rutland for (i = 0; i < vdso_info[abi].vdso_pages; i++) 123d53b5c01SAndrei Vagin vdso_pagelist[i] = pfn_to_page(pfn + i); 124c7aa2d71SVincenzo Frascino 125d53b5c01SAndrei Vagin vdso_info[abi].cm->pages = vdso_pagelist; 126c7aa2d71SVincenzo Frascino 127c7aa2d71SVincenzo Frascino return 0; 128c7aa2d71SVincenzo Frascino } 129c7aa2d71SVincenzo Frascino 1301b6867d2SAndrei Vagin #ifdef CONFIG_TIME_NS 1313503d56cSAndrei Vagin struct vdso_data *arch_get_vdso_data(void *vvar_page) 1323503d56cSAndrei Vagin { 1333503d56cSAndrei Vagin return (struct vdso_data *)(vvar_page); 1343503d56cSAndrei Vagin } 1353503d56cSAndrei Vagin 1361b6867d2SAndrei Vagin /* 1371b6867d2SAndrei Vagin * The vvar mapping contains data for a specific time namespace, so when a task 1381b6867d2SAndrei Vagin * changes namespace we must unmap its vvar data for the old namespace. 1391b6867d2SAndrei Vagin * Subsequent faults will map in data for the new namespace. 1401b6867d2SAndrei Vagin * 1411b6867d2SAndrei Vagin * For more details see timens_setup_vdso_data(). 1421b6867d2SAndrei Vagin */ 1431b6867d2SAndrei Vagin int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) 1441b6867d2SAndrei Vagin { 1451b6867d2SAndrei Vagin struct mm_struct *mm = task->mm; 1461b6867d2SAndrei Vagin struct vm_area_struct *vma; 1471b6867d2SAndrei Vagin 1481b6867d2SAndrei Vagin mmap_read_lock(mm); 1491b6867d2SAndrei Vagin 1501b6867d2SAndrei Vagin for (vma = mm->mmap; vma; vma = vma->vm_next) { 1511b6867d2SAndrei Vagin unsigned long size = vma->vm_end - vma->vm_start; 1521b6867d2SAndrei Vagin 1531b6867d2SAndrei Vagin if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA64].dm)) 1541b6867d2SAndrei Vagin zap_page_range(vma, vma->vm_start, size); 1551b6867d2SAndrei Vagin #ifdef CONFIG_COMPAT_VDSO 1561b6867d2SAndrei Vagin if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA32].dm)) 1571b6867d2SAndrei Vagin zap_page_range(vma, vma->vm_start, size); 1581b6867d2SAndrei Vagin #endif 1591b6867d2SAndrei Vagin } 1601b6867d2SAndrei Vagin 1611b6867d2SAndrei Vagin mmap_read_unlock(mm); 1621b6867d2SAndrei Vagin return 0; 1631b6867d2SAndrei Vagin } 164ee3cda8eSAndrei Vagin 165ee3cda8eSAndrei Vagin static struct page *find_timens_vvar_page(struct vm_area_struct *vma) 166ee3cda8eSAndrei Vagin { 167ee3cda8eSAndrei Vagin if (likely(vma->vm_mm == current->mm)) 168ee3cda8eSAndrei Vagin return current->nsproxy->time_ns->vvar_page; 169ee3cda8eSAndrei Vagin 170ee3cda8eSAndrei Vagin /* 171ee3cda8eSAndrei Vagin * VM_PFNMAP | VM_IO protect .fault() handler from being called 172ee3cda8eSAndrei Vagin * through interfaces like /proc/$pid/mem or 173ee3cda8eSAndrei Vagin * process_vm_{readv,writev}() as long as there's no .access() 174ee3cda8eSAndrei Vagin * in special_mapping_vmops. 175ee3cda8eSAndrei Vagin * For more details check_vma_flags() and __access_remote_vm() 176ee3cda8eSAndrei Vagin */ 177ee3cda8eSAndrei Vagin WARN(1, "vvar_page accessed remotely"); 178ee3cda8eSAndrei Vagin 179ee3cda8eSAndrei Vagin return NULL; 180ee3cda8eSAndrei Vagin } 181ee3cda8eSAndrei Vagin #else 182ee3cda8eSAndrei Vagin static struct page *find_timens_vvar_page(struct vm_area_struct *vma) 183ee3cda8eSAndrei Vagin { 184ee3cda8eSAndrei Vagin return NULL; 185ee3cda8eSAndrei Vagin } 1861b6867d2SAndrei Vagin #endif 1871b6867d2SAndrei Vagin 188d53b5c01SAndrei Vagin static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, 189d53b5c01SAndrei Vagin struct vm_area_struct *vma, struct vm_fault *vmf) 190d53b5c01SAndrei Vagin { 191ee3cda8eSAndrei Vagin struct page *timens_page = find_timens_vvar_page(vma); 192ee3cda8eSAndrei Vagin unsigned long pfn; 193ee3cda8eSAndrei Vagin 194ee3cda8eSAndrei Vagin switch (vmf->pgoff) { 195ee3cda8eSAndrei Vagin case VVAR_DATA_PAGE_OFFSET: 196ee3cda8eSAndrei Vagin if (timens_page) 197ee3cda8eSAndrei Vagin pfn = page_to_pfn(timens_page); 198ee3cda8eSAndrei Vagin else 199ee3cda8eSAndrei Vagin pfn = sym_to_pfn(vdso_data); 200ee3cda8eSAndrei Vagin break; 201ee3cda8eSAndrei Vagin #ifdef CONFIG_TIME_NS 202ee3cda8eSAndrei Vagin case VVAR_TIMENS_PAGE_OFFSET: 203ee3cda8eSAndrei Vagin /* 204ee3cda8eSAndrei Vagin * If a task belongs to a time namespace then a namespace 205ee3cda8eSAndrei Vagin * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and 206ee3cda8eSAndrei Vagin * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET 207ee3cda8eSAndrei Vagin * offset. 208ee3cda8eSAndrei Vagin * See also the comment near timens_setup_vdso_data(). 209ee3cda8eSAndrei Vagin */ 210ee3cda8eSAndrei Vagin if (!timens_page) 211d53b5c01SAndrei Vagin return VM_FAULT_SIGBUS; 212ee3cda8eSAndrei Vagin pfn = sym_to_pfn(vdso_data); 213ee3cda8eSAndrei Vagin break; 214ee3cda8eSAndrei Vagin #endif /* CONFIG_TIME_NS */ 215ee3cda8eSAndrei Vagin default: 216ee3cda8eSAndrei Vagin return VM_FAULT_SIGBUS; 217ee3cda8eSAndrei Vagin } 218ee3cda8eSAndrei Vagin 219ee3cda8eSAndrei Vagin return vmf_insert_pfn(vma, vmf->address, pfn); 220d53b5c01SAndrei Vagin } 221d53b5c01SAndrei Vagin 222bcf99643SAndrei Vagin static int vvar_mremap(const struct vm_special_mapping *sm, 223bcf99643SAndrei Vagin struct vm_area_struct *new_vma) 224bcf99643SAndrei Vagin { 225bcf99643SAndrei Vagin unsigned long new_size = new_vma->vm_end - new_vma->vm_start; 226bcf99643SAndrei Vagin 227bcf99643SAndrei Vagin if (new_size != VVAR_NR_PAGES * PAGE_SIZE) 228bcf99643SAndrei Vagin return -EINVAL; 229bcf99643SAndrei Vagin 230bcf99643SAndrei Vagin return 0; 231bcf99643SAndrei Vagin } 232bcf99643SAndrei Vagin 233d3418f38SMark Rutland static int __setup_additional_pages(enum vdso_abi abi, 234c7aa2d71SVincenzo Frascino struct mm_struct *mm, 235c7aa2d71SVincenzo Frascino struct linux_binprm *bprm, 236c7aa2d71SVincenzo Frascino int uses_interp) 237c7aa2d71SVincenzo Frascino { 238c7aa2d71SVincenzo Frascino unsigned long vdso_base, vdso_text_len, vdso_mapping_len; 239bf740a90SMark Brown unsigned long gp_flags = 0; 240c7aa2d71SVincenzo Frascino void *ret; 241c7aa2d71SVincenzo Frascino 2423503d56cSAndrei Vagin BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES); 2433503d56cSAndrei Vagin 244d3418f38SMark Rutland vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT; 245c7aa2d71SVincenzo Frascino /* Be sure to map the data page */ 2463503d56cSAndrei Vagin vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE; 247c7aa2d71SVincenzo Frascino 248c7aa2d71SVincenzo Frascino vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0); 249c7aa2d71SVincenzo Frascino if (IS_ERR_VALUE(vdso_base)) { 250c7aa2d71SVincenzo Frascino ret = ERR_PTR(vdso_base); 251c7aa2d71SVincenzo Frascino goto up_fail; 252c7aa2d71SVincenzo Frascino } 253c7aa2d71SVincenzo Frascino 2543503d56cSAndrei Vagin ret = _install_special_mapping(mm, vdso_base, VVAR_NR_PAGES * PAGE_SIZE, 255d53b5c01SAndrei Vagin VM_READ|VM_MAYREAD|VM_PFNMAP, 256d3418f38SMark Rutland vdso_info[abi].dm); 257c7aa2d71SVincenzo Frascino if (IS_ERR(ret)) 258c7aa2d71SVincenzo Frascino goto up_fail; 259c7aa2d71SVincenzo Frascino 260bf740a90SMark Brown if (IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) && system_supports_bti()) 261bf740a90SMark Brown gp_flags = VM_ARM64_BTI; 262bf740a90SMark Brown 2633503d56cSAndrei Vagin vdso_base += VVAR_NR_PAGES * PAGE_SIZE; 264c7aa2d71SVincenzo Frascino mm->context.vdso = (void *)vdso_base; 265c7aa2d71SVincenzo Frascino ret = _install_special_mapping(mm, vdso_base, vdso_text_len, 266bf740a90SMark Brown VM_READ|VM_EXEC|gp_flags| 267c7aa2d71SVincenzo Frascino VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 268d3418f38SMark Rutland vdso_info[abi].cm); 269c7aa2d71SVincenzo Frascino if (IS_ERR(ret)) 270c7aa2d71SVincenzo Frascino goto up_fail; 271c7aa2d71SVincenzo Frascino 272c7aa2d71SVincenzo Frascino return 0; 273c7aa2d71SVincenzo Frascino 274c7aa2d71SVincenzo Frascino up_fail: 275c7aa2d71SVincenzo Frascino mm->context.vdso = NULL; 276c7aa2d71SVincenzo Frascino return PTR_ERR(ret); 277c7aa2d71SVincenzo Frascino } 278c7aa2d71SVincenzo Frascino 2799031fefdSWill Deacon #ifdef CONFIG_COMPAT 2809031fefdSWill Deacon /* 2819031fefdSWill Deacon * Create and map the vectors page for AArch32 tasks. 2829031fefdSWill Deacon */ 2837c1deeebSVincenzo Frascino static int aarch32_vdso_mremap(const struct vm_special_mapping *sm, 2847c1deeebSVincenzo Frascino struct vm_area_struct *new_vma) 2857c1deeebSVincenzo Frascino { 286d3418f38SMark Rutland return __vdso_remap(VDSO_ABI_AA32, sm, new_vma); 2877c1deeebSVincenzo Frascino } 2887c1deeebSVincenzo Frascino 2891d09094aSMark Rutland enum aarch32_map { 2901d09094aSMark Rutland AA32_MAP_VECTORS, /* kuser helpers */ 2910cbc2659SWill Deacon AA32_MAP_SIGPAGE, 2921d09094aSMark Rutland AA32_MAP_VVAR, 2931d09094aSMark Rutland AA32_MAP_VDSO, 2941d09094aSMark Rutland }; 29574fc72e7SMark Rutland 29674fc72e7SMark Rutland static struct page *aarch32_vectors_page __ro_after_init; 29774fc72e7SMark Rutland static struct page *aarch32_sig_page __ro_after_init; 29874fc72e7SMark Rutland 2991d09094aSMark Rutland static struct vm_special_mapping aarch32_vdso_maps[] = { 3001d09094aSMark Rutland [AA32_MAP_VECTORS] = { 3010d747f65SVincenzo Frascino .name = "[vectors]", /* ABI */ 30274fc72e7SMark Rutland .pages = &aarch32_vectors_page, 3030d747f65SVincenzo Frascino }, 3040cbc2659SWill Deacon [AA32_MAP_SIGPAGE] = { 3050cbc2659SWill Deacon .name = "[sigpage]", /* ABI */ 3060cbc2659SWill Deacon .pages = &aarch32_sig_page, 3070cbc2659SWill Deacon }, 3081d09094aSMark Rutland [AA32_MAP_VVAR] = { 3097c1deeebSVincenzo Frascino .name = "[vvar]", 310d53b5c01SAndrei Vagin .fault = vvar_fault, 311bcf99643SAndrei Vagin .mremap = vvar_mremap, 3127c1deeebSVincenzo Frascino }, 3131d09094aSMark Rutland [AA32_MAP_VDSO] = { 3147c1deeebSVincenzo Frascino .name = "[vdso]", 3157c1deeebSVincenzo Frascino .mremap = aarch32_vdso_mremap, 3167c1deeebSVincenzo Frascino }, 3170d747f65SVincenzo Frascino }; 3189031fefdSWill Deacon 3191255a734SVincenzo Frascino static int aarch32_alloc_kuser_vdso_page(void) 3209031fefdSWill Deacon { 3219031fefdSWill Deacon extern char __kuser_helper_start[], __kuser_helper_end[]; 3229031fefdSWill Deacon int kuser_sz = __kuser_helper_end - __kuser_helper_start; 3231255a734SVincenzo Frascino unsigned long vdso_page; 3249031fefdSWill Deacon 325af1b3cf2SVincenzo Frascino if (!IS_ENABLED(CONFIG_KUSER_HELPERS)) 326af1b3cf2SVincenzo Frascino return 0; 327af1b3cf2SVincenzo Frascino 3281255a734SVincenzo Frascino vdso_page = get_zeroed_page(GFP_ATOMIC); 3291255a734SVincenzo Frascino if (!vdso_page) 3309031fefdSWill Deacon return -ENOMEM; 3319031fefdSWill Deacon 3321255a734SVincenzo Frascino memcpy((void *)(vdso_page + 0x1000 - kuser_sz), __kuser_helper_start, 3331255a734SVincenzo Frascino kuser_sz); 33474fc72e7SMark Rutland aarch32_vectors_page = virt_to_page(vdso_page); 33574fc72e7SMark Rutland flush_dcache_page(aarch32_vectors_page); 3361255a734SVincenzo Frascino return 0; 3370d747f65SVincenzo Frascino } 3380d747f65SVincenzo Frascino 339a39060b0SWill Deacon static int aarch32_alloc_sigpage(void) 3401255a734SVincenzo Frascino { 3411255a734SVincenzo Frascino extern char __aarch32_sigret_code_start[], __aarch32_sigret_code_end[]; 3421255a734SVincenzo Frascino int sigret_sz = __aarch32_sigret_code_end - __aarch32_sigret_code_start; 3431255a734SVincenzo Frascino unsigned long sigpage; 3449031fefdSWill Deacon 3451255a734SVincenzo Frascino sigpage = get_zeroed_page(GFP_ATOMIC); 3461255a734SVincenzo Frascino if (!sigpage) 3471255a734SVincenzo Frascino return -ENOMEM; 3489031fefdSWill Deacon 3491255a734SVincenzo Frascino memcpy((void *)sigpage, __aarch32_sigret_code_start, sigret_sz); 35074fc72e7SMark Rutland aarch32_sig_page = virt_to_page(sigpage); 35174fc72e7SMark Rutland flush_dcache_page(aarch32_sig_page); 352a39060b0SWill Deacon return 0; 353a39060b0SWill Deacon } 3540d747f65SVincenzo Frascino 355a39060b0SWill Deacon static int __aarch32_alloc_vdso_pages(void) 356a39060b0SWill Deacon { 3570cbc2659SWill Deacon 3580cbc2659SWill Deacon if (!IS_ENABLED(CONFIG_COMPAT_VDSO)) 3590cbc2659SWill Deacon return 0; 3600cbc2659SWill Deacon 361a39060b0SWill Deacon vdso_info[VDSO_ABI_AA32].dm = &aarch32_vdso_maps[AA32_MAP_VVAR]; 362a39060b0SWill Deacon vdso_info[VDSO_ABI_AA32].cm = &aarch32_vdso_maps[AA32_MAP_VDSO]; 3639031fefdSWill Deacon 364a39060b0SWill Deacon return __vdso_init(VDSO_ABI_AA32); 3659031fefdSWill Deacon } 3667c1deeebSVincenzo Frascino 3677c1deeebSVincenzo Frascino static int __init aarch32_alloc_vdso_pages(void) 3687c1deeebSVincenzo Frascino { 369a39060b0SWill Deacon int ret; 370a39060b0SWill Deacon 371a39060b0SWill Deacon ret = __aarch32_alloc_vdso_pages(); 372a39060b0SWill Deacon if (ret) 373a39060b0SWill Deacon return ret; 374a39060b0SWill Deacon 375a39060b0SWill Deacon ret = aarch32_alloc_sigpage(); 376a39060b0SWill Deacon if (ret) 377a39060b0SWill Deacon return ret; 378a39060b0SWill Deacon 379a39060b0SWill Deacon return aarch32_alloc_kuser_vdso_page(); 3807c1deeebSVincenzo Frascino } 3810d747f65SVincenzo Frascino arch_initcall(aarch32_alloc_vdso_pages); 3829031fefdSWill Deacon 3830d747f65SVincenzo Frascino static int aarch32_kuser_helpers_setup(struct mm_struct *mm) 3840d747f65SVincenzo Frascino { 3850d747f65SVincenzo Frascino void *ret; 3860d747f65SVincenzo Frascino 387af1b3cf2SVincenzo Frascino if (!IS_ENABLED(CONFIG_KUSER_HELPERS)) 388af1b3cf2SVincenzo Frascino return 0; 389af1b3cf2SVincenzo Frascino 3900d747f65SVincenzo Frascino /* 3910d747f65SVincenzo Frascino * Avoid VM_MAYWRITE for compatibility with arch/arm/, where it's 3920d747f65SVincenzo Frascino * not safe to CoW the page containing the CPU exception vectors. 3930d747f65SVincenzo Frascino */ 3940d747f65SVincenzo Frascino ret = _install_special_mapping(mm, AARCH32_VECTORS_BASE, PAGE_SIZE, 3950d747f65SVincenzo Frascino VM_READ | VM_EXEC | 3960d747f65SVincenzo Frascino VM_MAYREAD | VM_MAYEXEC, 3971d09094aSMark Rutland &aarch32_vdso_maps[AA32_MAP_VECTORS]); 3980d747f65SVincenzo Frascino 3990d747f65SVincenzo Frascino return PTR_ERR_OR_ZERO(ret); 4000d747f65SVincenzo Frascino } 4010d747f65SVincenzo Frascino 4020d747f65SVincenzo Frascino static int aarch32_sigreturn_setup(struct mm_struct *mm) 4030d747f65SVincenzo Frascino { 4040d747f65SVincenzo Frascino unsigned long addr; 4050d747f65SVincenzo Frascino void *ret; 4060d747f65SVincenzo Frascino 4070d747f65SVincenzo Frascino addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0); 4080d747f65SVincenzo Frascino if (IS_ERR_VALUE(addr)) { 4090d747f65SVincenzo Frascino ret = ERR_PTR(addr); 4100d747f65SVincenzo Frascino goto out; 4110d747f65SVincenzo Frascino } 4120d747f65SVincenzo Frascino 4130d747f65SVincenzo Frascino /* 4140d747f65SVincenzo Frascino * VM_MAYWRITE is required to allow gdb to Copy-on-Write and 4150d747f65SVincenzo Frascino * set breakpoints. 4160d747f65SVincenzo Frascino */ 4170d747f65SVincenzo Frascino ret = _install_special_mapping(mm, addr, PAGE_SIZE, 4180d747f65SVincenzo Frascino VM_READ | VM_EXEC | VM_MAYREAD | 4190d747f65SVincenzo Frascino VM_MAYWRITE | VM_MAYEXEC, 4201d09094aSMark Rutland &aarch32_vdso_maps[AA32_MAP_SIGPAGE]); 4210d747f65SVincenzo Frascino if (IS_ERR(ret)) 4220d747f65SVincenzo Frascino goto out; 4230d747f65SVincenzo Frascino 424a39060b0SWill Deacon mm->context.sigpage = (void *)addr; 4250d747f65SVincenzo Frascino 4260d747f65SVincenzo Frascino out: 4270d747f65SVincenzo Frascino return PTR_ERR_OR_ZERO(ret); 4280d747f65SVincenzo Frascino } 4290d747f65SVincenzo Frascino 4300d747f65SVincenzo Frascino int aarch32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 4319031fefdSWill Deacon { 4329031fefdSWill Deacon struct mm_struct *mm = current->mm; 4330d747f65SVincenzo Frascino int ret; 4349031fefdSWill Deacon 435d8ed45c5SMichel Lespinasse if (mmap_write_lock_killable(mm)) 43669048176SMichal Hocko return -EINTR; 4379031fefdSWill Deacon 4380d747f65SVincenzo Frascino ret = aarch32_kuser_helpers_setup(mm); 4390d747f65SVincenzo Frascino if (ret) 4400d747f65SVincenzo Frascino goto out; 4419031fefdSWill Deacon 4420cbc2659SWill Deacon if (IS_ENABLED(CONFIG_COMPAT_VDSO)) { 443d3418f38SMark Rutland ret = __setup_additional_pages(VDSO_ABI_AA32, 4447c1deeebSVincenzo Frascino mm, 4457c1deeebSVincenzo Frascino bprm, 4467c1deeebSVincenzo Frascino uses_interp); 447a39060b0SWill Deacon if (ret) 448a39060b0SWill Deacon goto out; 4490cbc2659SWill Deacon } 4500d747f65SVincenzo Frascino 451a39060b0SWill Deacon ret = aarch32_sigreturn_setup(mm); 4520d747f65SVincenzo Frascino out: 453d8ed45c5SMichel Lespinasse mmap_write_unlock(mm); 4540d747f65SVincenzo Frascino return ret; 4559031fefdSWill Deacon } 4569031fefdSWill Deacon #endif /* CONFIG_COMPAT */ 4579031fefdSWill Deacon 45873958695SDmitry Safonov static int vdso_mremap(const struct vm_special_mapping *sm, 45973958695SDmitry Safonov struct vm_area_struct *new_vma) 46073958695SDmitry Safonov { 461d3418f38SMark Rutland return __vdso_remap(VDSO_ABI_AA64, sm, new_vma); 46273958695SDmitry Safonov } 46373958695SDmitry Safonov 4641d09094aSMark Rutland enum aarch64_map { 4651d09094aSMark Rutland AA64_MAP_VVAR, 4661d09094aSMark Rutland AA64_MAP_VDSO, 4671d09094aSMark Rutland }; 4681d09094aSMark Rutland 4691d09094aSMark Rutland static struct vm_special_mapping aarch64_vdso_maps[] __ro_after_init = { 4701d09094aSMark Rutland [AA64_MAP_VVAR] = { 4715a9e3e15SJisheng Zhang .name = "[vvar]", 472d53b5c01SAndrei Vagin .fault = vvar_fault, 473bcf99643SAndrei Vagin .mremap = vvar_mremap, 4745a9e3e15SJisheng Zhang }, 4751d09094aSMark Rutland [AA64_MAP_VDSO] = { 4765a9e3e15SJisheng Zhang .name = "[vdso]", 47773958695SDmitry Safonov .mremap = vdso_mremap, 4785a9e3e15SJisheng Zhang }, 4795a9e3e15SJisheng Zhang }; 4802fea7f6cSWill Deacon 4819031fefdSWill Deacon static int __init vdso_init(void) 4829031fefdSWill Deacon { 4831d09094aSMark Rutland vdso_info[VDSO_ABI_AA64].dm = &aarch64_vdso_maps[AA64_MAP_VVAR]; 4841d09094aSMark Rutland vdso_info[VDSO_ABI_AA64].cm = &aarch64_vdso_maps[AA64_MAP_VDSO]; 48516fb1a9bSNathan Lynch 486d3418f38SMark Rutland return __vdso_init(VDSO_ABI_AA64); 4879031fefdSWill Deacon } 4889031fefdSWill Deacon arch_initcall(vdso_init); 4899031fefdSWill Deacon 4909031fefdSWill Deacon int arch_setup_additional_pages(struct linux_binprm *bprm, 4919031fefdSWill Deacon int uses_interp) 4929031fefdSWill Deacon { 4939031fefdSWill Deacon struct mm_struct *mm = current->mm; 494c7aa2d71SVincenzo Frascino int ret; 4959031fefdSWill Deacon 496d8ed45c5SMichel Lespinasse if (mmap_write_lock_killable(mm)) 49769048176SMichal Hocko return -EINTR; 49887154938SWill Deacon 499d3418f38SMark Rutland ret = __setup_additional_pages(VDSO_ABI_AA64, 500c7aa2d71SVincenzo Frascino mm, 501c7aa2d71SVincenzo Frascino bprm, 502c7aa2d71SVincenzo Frascino uses_interp); 503601255aeSWill Deacon 504d8ed45c5SMichel Lespinasse mmap_write_unlock(mm); 5059031fefdSWill Deacon 506c7aa2d71SVincenzo Frascino return ret; 5079031fefdSWill Deacon } 508