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

Pull x86 fixes from Thomas Gleixner:
 "Two last minute fixes:

   - Prevent value evaluation via functions happening in the user access
     enabled region of __put_user() (put another way: make sure to
     evaluate the value to be stored in user space _before_ enabling
     user space accesses)

   - Correct the definition of a Hyper-V hypercall constant"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/hyper-v: Fix definition of HV_MAX_FLUSH_REP_COUNT
  x86/uaccess: Don't leak the AC flag into __put_user() value evaluation

2 files changed, 5 insertions, 3 deletions

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 705dafc2d11a..2bdbbbcfa393 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -841,7 +841,7 @@ union hv_gpa_page_range {
  * count is equal with how many entries of union hv_gpa_page_range can
  * be populated into the input parameter page.
  */
-#define HV_MAX_FLUSH_REP_COUNT (PAGE_SIZE - 2 * sizeof(u64) /   \
+#define HV_MAX_FLUSH_REP_COUNT ((PAGE_SIZE - 2 * sizeof(u64)) / \
                                 sizeof(union hv_gpa_page_range))
 
 struct hv_guest_mapping_flush_list {
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 780f2b42c8ef..c1334aaaa78d 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -284,7 +284,7 @@ do {									\
                 __put_user_goto(x, ptr, "l", "k", "ir", label);         \
                 break;                                                  \
         case 8:                                                         \
-                __put_user_goto_u64((__typeof__(*ptr))(x), ptr, label); \
+                __put_user_goto_u64(x, ptr, label);                     \
                 break;                                                  \
         default:                                                        \
                 __put_user_bad();                                       \
@@ -431,8 +431,10 @@ do {									\
 ({                                                              \
         __label__ __pu_label;                                   \
         int __pu_err = -EFAULT;                                 \
+        __typeof__(*(ptr)) __pu_val;                            \
+        __pu_val = x;                                           \
         __uaccess_begin();                                      \
-        __put_user_size((x), (ptr), (size), __pu_label);        \
+        __put_user_size(__pu_val, (ptr), (size), __pu_label);   \
         __pu_err = 0;                                           \
 __pu_label:                                                     \
         __uaccess_end();                                        \