From 01f76386b0ac0b1c1094456c8f43ea6085fc49d2 Mon Sep 17 00:00:00 2001 From: Vincent Chen Date: Tue, 9 Jun 2020 22:14:49 +0800 Subject: [PATCH] riscv: set the permission of vdso_data to read-only The original vdso_data page is empty, so the permission of the vdso_data page can be the same with the vdso text page. After introducing the vDSO common flow, the vdso_data is not empty and the permission should be changed to read-only. Signed-off-by: Vincent Chen Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/vdso.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c index 70b6461a6387..94450332aa4f 100644 --- a/arch/riscv/kernel/vdso.c +++ b/arch/riscv/kernel/vdso.c @@ -79,13 +79,22 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, */ mm->context.vdso = (void *)vdso_base; - ret = install_special_mapping(mm, vdso_base, vdso_len, + ret = + install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT, (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC), vdso_pagelist); + if (unlikely(ret)) { + mm->context.vdso = NULL; + goto end; + } + + vdso_base += (vdso_pages << PAGE_SHIFT); + ret = install_special_mapping(mm, vdso_base, PAGE_SIZE, + (VM_READ | VM_MAYREAD), &vdso_pagelist[vdso_pages]); + if (unlikely(ret)) mm->context.vdso = NULL; - end: up_write(&mm->mmap_sem); return ret; @@ -95,5 +104,8 @@ const char *arch_vma_name(struct vm_area_struct *vma) { if (vma->vm_mm && (vma->vm_start == (long)vma->vm_mm->context.vdso)) return "[vdso]"; + if (vma->vm_mm && (vma->vm_start == + (long)vma->vm_mm->context.vdso + PAGE_SIZE)) + return "[vdso_data]"; return NULL; }