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d2862bb9d9
The generic storage implementation provides the same features as the custom one. However it can be shared between architectures, making maintenance easier. Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-10-13a4669dfc8c@linutronix.de
122 lines
2.7 KiB
C
122 lines
2.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Author: Huacai Chen <chenhuacai@loongson.cn>
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* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
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*/
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#include <linux/binfmts.h>
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#include <linux/elf.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/ioport.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/random.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/vdso_datastore.h>
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#include <asm/page.h>
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#include <asm/vdso.h>
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#include <vdso/helpers.h>
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#include <vdso/vsyscall.h>
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#include <vdso/datapage.h>
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#include <generated/vdso-offsets.h>
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extern char vdso_start[], vdso_end[];
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static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma)
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{
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current->mm->context.vdso = (void *)(new_vma->vm_start);
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return 0;
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}
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struct loongarch_vdso_info vdso_info = {
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.vdso = vdso_start,
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.code_mapping = {
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.name = "[vdso]",
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.mremap = vdso_mremap,
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},
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.offset_sigreturn = vdso_offset_sigreturn,
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};
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static int __init init_vdso(void)
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{
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unsigned long i, cpu, pfn;
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BUG_ON(!PAGE_ALIGNED(vdso_info.vdso));
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for_each_possible_cpu(cpu)
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vdso_k_arch_data->pdata[cpu].node = cpu_to_node(cpu);
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vdso_info.size = PAGE_ALIGN(vdso_end - vdso_start);
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vdso_info.code_mapping.pages =
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kcalloc(vdso_info.size / PAGE_SIZE, sizeof(struct page *), GFP_KERNEL);
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pfn = __phys_to_pfn(__pa_symbol(vdso_info.vdso));
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for (i = 0; i < vdso_info.size / PAGE_SIZE; i++)
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vdso_info.code_mapping.pages[i] = pfn_to_page(pfn + i);
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return 0;
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}
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subsys_initcall(init_vdso);
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static unsigned long vdso_base(void)
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{
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unsigned long base = STACK_TOP;
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if (current->flags & PF_RANDOMIZE) {
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base += get_random_u32_below(VDSO_RANDOMIZE_SIZE);
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base = PAGE_ALIGN(base);
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}
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return base;
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}
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int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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{
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int ret;
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unsigned long size, data_addr, vdso_addr;
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struct mm_struct *mm = current->mm;
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struct vm_area_struct *vma;
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struct loongarch_vdso_info *info = current->thread.vdso;
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if (mmap_write_lock_killable(mm))
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return -EINTR;
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/*
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* Determine total area size. This includes the VDSO data itself
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* and the data pages.
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*/
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size = VVAR_SIZE + info->size;
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data_addr = get_unmapped_area(NULL, vdso_base(), size, 0, 0);
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if (IS_ERR_VALUE(data_addr)) {
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ret = data_addr;
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goto out;
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}
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vma = vdso_install_vvar_mapping(mm, data_addr);
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if (IS_ERR(vma)) {
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ret = PTR_ERR(vma);
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goto out;
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}
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vdso_addr = data_addr + VVAR_SIZE;
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vma = _install_special_mapping(mm, vdso_addr, info->size,
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VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
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&info->code_mapping);
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if (IS_ERR(vma)) {
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ret = PTR_ERR(vma);
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goto out;
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}
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mm->context.vdso = (void *)vdso_addr;
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ret = 0;
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out:
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mmap_write_unlock(mm);
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return ret;
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}
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