arm64: fix address limit problem with TASK_SIZE_MAX

hulk inclusion
category: bugfix
bugzilla: 51408 https://e.gitee.com/open_euler/issues/list?issue=I4SCW7
CVE: NA

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In commit e29beeac53c8 ("arm64: uaccess: remove set_fs()"),
thread_info->addr_limit and macro USER_DS has been removed and replace
by macro TASK_SIZE_MAX. However the address limit set by TASK_SIZE_MAX
is incorrect in compat mode, see commit 2ef73d5148e ("[Huawei] arm64: fix
current_thread_info()->addr_limit setup") for detail.

Fix the problem by modifying TASK_SIZE_MAX definition in compat mode.
Signed-off-by: NChen Jiahao <chenjiahao16@huawei.com>
Signed-off-by: NZhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Reviewed-by: NChang Liao <liaochang1@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm64/include/asm/processor.h

@@ -47,9 +47,10 @@
 
 #define DEFAULT_MAP_WINDOW_64	(UL(1) << VA_BITS_MIN)
 #define TASK_SIZE_64		(UL(1) << vabits_actual)
-#define TASK_SIZE_MAX		(UL(1) << VA_BITS)
 
 #ifdef CONFIG_COMPAT
+#define TASK_SIZE_MAX		(is_compat_task() ? \
+				UL(0x100000000) : (UL(1) << VA_BITS))
 #if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS)
 /*
  * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied
@@ -66,6 +67,7 @@
 #define DEFAULT_MAP_WINDOW	(is_compat_task() ? \
 				TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64)
 #else
+#define TASK_SIZE_MAX		(UL(1) << VA_BITS)
 #define TASK_SIZE		TASK_SIZE_64
 #define DEFAULT_MAP_WINDOW	DEFAULT_MAP_WINDOW_64
 #endif /* CONFIG_COMPAT */