diff options
Diffstat (limited to 'arch/arm64/kernel/vdso.c')
-rw-r--r-- | arch/arm64/kernel/vdso.c | 155 |
1 files changed, 73 insertions, 82 deletions
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 033a48f30dbb..d51a898fd60f 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -33,20 +33,14 @@ extern char vdso_start[], vdso_end[]; extern char vdso32_start[], vdso32_end[]; #endif /* CONFIG_COMPAT_VDSO */ -/* vdso_lookup arch_index */ -enum arch_vdso_type { - ARM64_VDSO = 0, +enum vdso_abi { + VDSO_ABI_AA64, #ifdef CONFIG_COMPAT_VDSO - ARM64_VDSO32 = 1, + VDSO_ABI_AA32, #endif /* CONFIG_COMPAT_VDSO */ }; -#ifdef CONFIG_COMPAT_VDSO -#define VDSO_TYPES (ARM64_VDSO32 + 1) -#else -#define VDSO_TYPES (ARM64_VDSO + 1) -#endif /* CONFIG_COMPAT_VDSO */ -struct __vdso_abi { +struct vdso_abi_info { const char *name; const char *vdso_code_start; const char *vdso_code_end; @@ -57,14 +51,14 @@ struct __vdso_abi { struct vm_special_mapping *cm; }; -static struct __vdso_abi vdso_lookup[VDSO_TYPES] __ro_after_init = { - { +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, @@ -81,13 +75,13 @@ static union { } vdso_data_store __page_aligned_data; struct vdso_data *vdso_data = vdso_data_store.data; -static int __vdso_remap(enum arch_vdso_type arch_index, +static int __vdso_remap(enum vdso_abi abi, const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { unsigned long new_size = new_vma->vm_end - new_vma->vm_start; - unsigned long vdso_size = vdso_lookup[arch_index].vdso_code_end - - vdso_lookup[arch_index].vdso_code_start; + unsigned long vdso_size = vdso_info[abi].vdso_code_end - + vdso_info[abi].vdso_code_start; if (vdso_size != new_size) return -EINVAL; @@ -97,24 +91,24 @@ static int __vdso_remap(enum arch_vdso_type arch_index, return 0; } -static int __vdso_init(enum arch_vdso_type arch_index) +static int __vdso_init(enum vdso_abi abi) { int i; struct page **vdso_pagelist; unsigned long pfn; - if (memcmp(vdso_lookup[arch_index].vdso_code_start, "\177ELF", 4)) { + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4)) { pr_err("vDSO is not a valid ELF object!\n"); return -EINVAL; } - vdso_lookup[arch_index].vdso_pages = ( - vdso_lookup[arch_index].vdso_code_end - - vdso_lookup[arch_index].vdso_code_start) >> + vdso_info[abi].vdso_pages = ( + vdso_info[abi].vdso_code_end - + vdso_info[abi].vdso_code_start) >> PAGE_SHIFT; /* Allocate the vDSO pagelist, plus a page for the data. */ - vdso_pagelist = kcalloc(vdso_lookup[arch_index].vdso_pages + 1, + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages + 1, sizeof(struct page *), GFP_KERNEL); if (vdso_pagelist == NULL) @@ -125,26 +119,27 @@ static int __vdso_init(enum arch_vdso_type arch_index) /* Grab the vDSO code pages. */ - pfn = sym_to_pfn(vdso_lookup[arch_index].vdso_code_start); + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start); - for (i = 0; i < vdso_lookup[arch_index].vdso_pages; i++) + for (i = 0; i < vdso_info[abi].vdso_pages; i++) vdso_pagelist[i + 1] = pfn_to_page(pfn + i); - vdso_lookup[arch_index].dm->pages = &vdso_pagelist[0]; - vdso_lookup[arch_index].cm->pages = &vdso_pagelist[1]; + vdso_info[abi].dm->pages = &vdso_pagelist[0]; + vdso_info[abi].cm->pages = &vdso_pagelist[1]; return 0; } -static int __setup_additional_pages(enum arch_vdso_type arch_index, +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; - vdso_text_len = vdso_lookup[arch_index].vdso_pages << PAGE_SHIFT; + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT; /* Be sure to map the data page */ vdso_mapping_len = vdso_text_len + PAGE_SIZE; @@ -156,16 +151,19 @@ static int __setup_additional_pages(enum arch_vdso_type arch_index, ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE, VM_READ|VM_MAYREAD, - vdso_lookup[arch_index].dm); + 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 += PAGE_SIZE; mm->context.vdso = (void *)vdso_base; ret = _install_special_mapping(mm, vdso_base, vdso_text_len, - VM_READ|VM_EXEC| + VM_READ|VM_EXEC|gp_flags| VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, - vdso_lookup[arch_index].cm); + vdso_info[abi].cm); if (IS_ERR(ret)) goto up_fail; @@ -184,46 +182,42 @@ up_fail: static int aarch32_vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { - return __vdso_remap(ARM64_VDSO32, sm, new_vma); + return __vdso_remap(VDSO_ABI_AA32, sm, new_vma); } #endif /* CONFIG_COMPAT_VDSO */ -/* - * aarch32_vdso_pages: - * 0 - kuser helpers - * 1 - sigreturn code - * or (CONFIG_COMPAT_VDSO): - * 0 - kuser helpers - * 1 - vdso data - * 2 - vdso code - */ -#define C_VECTORS 0 +enum aarch32_map { + AA32_MAP_VECTORS, /* kuser helpers */ #ifdef CONFIG_COMPAT_VDSO -#define C_VVAR 1 -#define C_VDSO 2 -#define C_PAGES (C_VDSO + 1) + AA32_MAP_VVAR, + AA32_MAP_VDSO, #else -#define C_SIGPAGE 1 -#define C_PAGES (C_SIGPAGE + 1) -#endif /* CONFIG_COMPAT_VDSO */ -static struct page *aarch32_vdso_pages[C_PAGES] __ro_after_init; -static struct vm_special_mapping aarch32_vdso_spec[C_PAGES] = { - { + AA32_MAP_SIGPAGE +#endif +}; + +static struct page *aarch32_vectors_page __ro_after_init; +#ifndef CONFIG_COMPAT_VDSO +static struct page *aarch32_sig_page __ro_after_init; +#endif + +static struct vm_special_mapping aarch32_vdso_maps[] = { + [AA32_MAP_VECTORS] = { .name = "[vectors]", /* ABI */ - .pages = &aarch32_vdso_pages[C_VECTORS], + .pages = &aarch32_vectors_page, }, #ifdef CONFIG_COMPAT_VDSO - { + [AA32_MAP_VVAR] = { .name = "[vvar]", }, - { + [AA32_MAP_VDSO] = { .name = "[vdso]", .mremap = aarch32_vdso_mremap, }, #else - { + [AA32_MAP_SIGPAGE] = { .name = "[sigpage]", /* ABI */ - .pages = &aarch32_vdso_pages[C_SIGPAGE], + .pages = &aarch32_sig_page, }, #endif /* CONFIG_COMPAT_VDSO */ }; @@ -243,8 +237,8 @@ static int aarch32_alloc_kuser_vdso_page(void) memcpy((void *)(vdso_page + 0x1000 - kuser_sz), __kuser_helper_start, kuser_sz); - aarch32_vdso_pages[C_VECTORS] = virt_to_page(vdso_page); - flush_dcache_page(aarch32_vdso_pages[C_VECTORS]); + aarch32_vectors_page = virt_to_page(vdso_page); + flush_dcache_page(aarch32_vectors_page); return 0; } @@ -253,10 +247,10 @@ static int __aarch32_alloc_vdso_pages(void) { int ret; - vdso_lookup[ARM64_VDSO32].dm = &aarch32_vdso_spec[C_VVAR]; - vdso_lookup[ARM64_VDSO32].cm = &aarch32_vdso_spec[C_VDSO]; + vdso_info[VDSO_ABI_AA32].dm = &aarch32_vdso_maps[AA32_MAP_VVAR]; + vdso_info[VDSO_ABI_AA32].cm = &aarch32_vdso_maps[AA32_MAP_VDSO]; - ret = __vdso_init(ARM64_VDSO32); + ret = __vdso_init(VDSO_ABI_AA32); if (ret) return ret; @@ -275,8 +269,8 @@ static int __aarch32_alloc_vdso_pages(void) return -ENOMEM; memcpy((void *)sigpage, __aarch32_sigret_code_start, sigret_sz); - aarch32_vdso_pages[C_SIGPAGE] = virt_to_page(sigpage); - flush_dcache_page(aarch32_vdso_pages[C_SIGPAGE]); + aarch32_sig_page = virt_to_page(sigpage); + flush_dcache_page(aarch32_sig_page); ret = aarch32_alloc_kuser_vdso_page(); if (ret) @@ -306,7 +300,7 @@ static int aarch32_kuser_helpers_setup(struct mm_struct *mm) ret = _install_special_mapping(mm, AARCH32_VECTORS_BASE, PAGE_SIZE, VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC, - &aarch32_vdso_spec[C_VECTORS]); + &aarch32_vdso_maps[AA32_MAP_VECTORS]); return PTR_ERR_OR_ZERO(ret); } @@ -330,7 +324,7 @@ static int aarch32_sigreturn_setup(struct mm_struct *mm) ret = _install_special_mapping(mm, addr, PAGE_SIZE, VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, - &aarch32_vdso_spec[C_SIGPAGE]); + &aarch32_vdso_maps[AA32_MAP_SIGPAGE]); if (IS_ERR(ret)) goto out; @@ -354,7 +348,7 @@ int aarch32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) goto out; #ifdef CONFIG_COMPAT_VDSO - ret = __setup_additional_pages(ARM64_VDSO32, + ret = __setup_additional_pages(VDSO_ABI_AA32, mm, bprm, uses_interp); @@ -371,22 +365,19 @@ out: static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { - return __vdso_remap(ARM64_VDSO, sm, new_vma); + return __vdso_remap(VDSO_ABI_AA64, sm, new_vma); } -/* - * aarch64_vdso_pages: - * 0 - vvar - * 1 - vdso - */ -#define A_VVAR 0 -#define A_VDSO 1 -#define A_PAGES (A_VDSO + 1) -static struct vm_special_mapping vdso_spec[A_PAGES] __ro_after_init = { - { +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]", }, - { + [AA64_MAP_VDSO] = { .name = "[vdso]", .mremap = vdso_mremap, }, @@ -394,10 +385,10 @@ static struct vm_special_mapping vdso_spec[A_PAGES] __ro_after_init = { static int __init vdso_init(void) { - vdso_lookup[ARM64_VDSO].dm = &vdso_spec[A_VVAR]; - vdso_lookup[ARM64_VDSO].cm = &vdso_spec[A_VDSO]; + 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(ARM64_VDSO); + return __vdso_init(VDSO_ABI_AA64); } arch_initcall(vdso_init); @@ -410,7 +401,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, if (down_write_killable(&mm->mmap_sem)) return -EINTR; - ret = __setup_additional_pages(ARM64_VDSO, + ret = __setup_additional_pages(VDSO_ABI_AA64, mm, bprm, uses_interp); |