diff options
| author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
|---|---|---|
| committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
| commit | 863981e96738983919de841ec669e157e6bdaeb0 (patch) | |
| tree | d6d89a12e7eb8017837c057935a2271290907f76 /arch/x86/mm/fault.c | |
| parent | 8dec7c70575785729a6a9e6719a955e9c545bcab (diff) | |
Linux-libre 4.7.1-gnupck-4.7.1-gnu
Diffstat (limited to 'arch/x86/mm/fault.c')
| -rw-r--r-- | arch/x86/mm/fault.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 9d995ea4f..441a68fcd 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -293,7 +293,7 @@ void vmalloc_sync_all(void) return; for (address = VMALLOC_START & PMD_MASK; - address >= TASK_SIZE && address < FIXADDR_TOP; + address >= TASK_SIZE_MAX && address < FIXADDR_TOP; address += PMD_SIZE) { struct page *page; @@ -859,8 +859,13 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, return; } #endif - /* Kernel addresses are always protection faults: */ - if (address >= TASK_SIZE) + + /* + * To avoid leaking information about the kernel page table + * layout, pretend that user-mode accesses to kernel addresses + * are always protection faults. + */ + if (address >= TASK_SIZE_MAX) error_code |= PF_PROT; if (likely(show_unhandled_signals)) |