diff options
| author |   Vincent Chen <vincent.chen@sifive.com> | 2020-06-09 22:14:49 +0800 |
|---|---|---|
| committer |   Palmer Dabbelt <palmerdabbelt@google.com> | 2020-06-10 19:47:35 -0700 |
| commit | 01f76386b0ac0b1c1094456c8f43ea6085fc49d2 (patch) | |
| tree | 889dc2bf914443827c96e1d7a7f6f4b449e742a2 /arch/riscv | |
| parent | riscv: use vDSO common flow to reduce the latency of the time-related functions (diff) | |
| download | linux-dev-01f76386b0ac0b1c1094456c8f43ea6085fc49d2.tar.xz linux-dev-01f76386b0ac0b1c1094456c8f43ea6085fc49d2.zip | |
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 <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'arch/riscv')
| -rw-r--r-- | arch/riscv/kernel/vdso.c | 16 |
1 files 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)) + 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; } |