nds32: Fix get_user/put_user macro expand pointer problem
authorZong Li <zong@andestech.com>
Mon, 13 Aug 2018 06:48:49 +0000 (14:48 +0800)
committerGreentime Hu <greentime@andestech.com>
Tue, 4 Sep 2018 06:45:16 +0000 (14:45 +0800)
The pointer argument of macro need to be taken out once first, and then
use the new pointer in the macro body.

In kernel/trace/trace.c, get_user(ch, ubuf++) causes the unexpected
increment after expand the macro.

Signed-off-by: Zong Li <zong@andestech.com>
Acked-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
arch/nds32/include/asm/uaccess.h

index 18a009f..3f771e0 100644 (file)
@@ -78,8 +78,9 @@ static inline void set_fs(mm_segment_t fs)
 #define get_user(x,p)                                                  \
 ({                                                                     \
        long __e = -EFAULT;                                             \
-       if(likely(access_ok(VERIFY_READ,  p, sizeof(*p)))) {            \
-               __e = __get_user(x,p);                                  \
+       const __typeof__(*(p)) __user *__p = (p);                       \
+       if(likely(access_ok(VERIFY_READ, __p, sizeof(*__p)))) {         \
+               __e = __get_user(x, __p);                               \
        } else                                                          \
                x = 0;                                                  \
        __e;                                                            \
@@ -99,10 +100,10 @@ static inline void set_fs(mm_segment_t fs)
 
 #define __get_user_err(x,ptr,err)                                      \
 do {                                                                   \
-       unsigned long __gu_addr = (unsigned long)(ptr);                 \
+       const __typeof__(*(ptr)) __user *__gu_addr = (ptr);             \
        unsigned long __gu_val;                                         \
-       __chk_user_ptr(ptr);                                            \
-       switch (sizeof(*(ptr))) {                                       \
+       __chk_user_ptr(__gu_addr);                                      \
+       switch (sizeof(*(__gu_addr))) {                                 \
        case 1:                                                         \
                __get_user_asm("lbi",__gu_val,__gu_addr,err);           \
                break;                                                  \
@@ -119,7 +120,7 @@ do {                                                                        \
                BUILD_BUG();                                            \
                break;                                                  \
        }                                                               \
-       (x) = (__typeof__(*(ptr)))__gu_val;                             \
+       (x) = (__typeof__(*(__gu_addr)))__gu_val;                       \
 } while (0)
 
 #define __get_user_asm(inst,x,addr,err)                                        \
@@ -169,8 +170,9 @@ do {                                                                        \
 #define put_user(x,p)                                                  \
 ({                                                                     \
        long __e = -EFAULT;                                             \
-       if(likely(access_ok(VERIFY_WRITE,  p, sizeof(*p)))) {           \
-               __e = __put_user(x,p);                                  \
+       __typeof__(*(p)) __user *__p = (p);                             \
+       if(likely(access_ok(VERIFY_WRITE, __p, sizeof(*__p)))) {        \
+               __e = __put_user(x, __p);                               \
        }                                                               \
        __e;                                                            \
 })
@@ -189,10 +191,10 @@ do {                                                                      \
 
 #define __put_user_err(x,ptr,err)                                      \
 do {                                                                   \
-       unsigned long __pu_addr = (unsigned long)(ptr);                 \
-       __typeof__(*(ptr)) __pu_val = (x);                              \
-       __chk_user_ptr(ptr);                                            \
-       switch (sizeof(*(ptr))) {                                       \
+       __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
+       __typeof__(*(__pu_addr)) __pu_val = (x);                        \
+       __chk_user_ptr(__pu_addr);                                      \
+       switch (sizeof(*(__pu_addr))) {                                 \
        case 1:                                                         \
                __put_user_asm("sbi",__pu_val,__pu_addr,err);           \
                break;                                                  \