diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/mm/pti.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c index f1fd52f449e0..ae3eb4f5d53b 100644 --- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -430,12 +430,24 @@ static inline bool pti_kernel_image_global_ok(void) */ void pti_clone_kernel_text(void) { + /* + * rodata is part of the kernel image and is normally + * readable on the filesystem or on the web. But, do not + * clone the areas past rodata, they might contain secrets. + */ unsigned long start = PFN_ALIGN(_text); - unsigned long end = ALIGN((unsigned long)_end, PMD_PAGE_SIZE); + unsigned long end = (unsigned long)__end_rodata_hpage_align; if (!pti_kernel_image_global_ok()) return; + pr_debug("mapping partial kernel image into user address space\n"); + + /* + * Note that this will undo _some_ of the work that + * pti_set_kernel_image_nonglobal() did to clear the + * global bit. + */ pti_clone_pmds(start, end, _PAGE_RW); } @@ -458,8 +470,6 @@ void pti_set_kernel_image_nonglobal(void) if (pti_kernel_image_global_ok()) return; - pr_debug("set kernel image non-global\n"); - set_memory_nonglobal(start, (end - start) >> PAGE_SHIFT); } |