Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
 "Misc fixes: EFI, entry code, pkeys and MPX fixes, TASK_SIZE cleanups
  and a tsc frequency table fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Switch from TASK_SIZE to TASK_SIZE_MAX in the page fault code
  x86/fsgsbase/64: Use TASK_SIZE_MAX for FSBASE/GSBASE upper limits
  x86/mm/mpx: Work around MPX erratum SKD046
  x86/entry/64: Fix stack return address retrieval in thunk
  x86/efi: Fix 7-parameter efi_call()s
  x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys
  x86/tsc: Add missing Cherrytrail frequency to the table

1 files changed, 8 insertions, 3 deletions

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 5ce1ed02f7e8..7d1fa7cd2374 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -292,7 +292,7 @@ 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;
 
@@ -854,8 +854,13 @@ __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))