patch-2.1.80 linux/include/asm-i386/uaccess.h

• Lines: 127
• Date: Tue Jan 20 16:51:57 1998
• Orig file: v2.1.79/linux/include/asm-i386/uaccess.h
• Orig date: Mon Jan 12 22:09:18 1998

diff -u --recursive --new-file v2.1.79/linux/include/asm-i386/uaccess.h linux/include/asm-i386/uaccess.h
@@ -51,6 +51,7 @@
 
 #define access_ok(type,addr,size) ( (__range_ok(addr,size) == 0) && \
 			 ((type) == VERIFY_READ || boot_cpu_data.wp_works_ok || \
+			 segment_eq(get_fs(),KERNEL_DS) || \
 			  __verify_write((void *)(addr),(size))))
 
 #endif /* CPU */
@@ -124,25 +125,108 @@
 extern void __put_user_2(void);
 extern void __put_user_4(void);
 
+extern void __put_user_bad(void);
+
 #define __put_user_x(size,ret,x,ptr)					\
 	__asm__ __volatile__("call __put_user_" #size			\
 		:"=a" (ret)						\
 		:"0" (ptr),"d" (x)					\
 		:"cx")
 
-#define put_user(x,ptr)							\
-({	int __ret_pu;							\
-	switch(sizeof (*(ptr))) {					\
-	case 1:  __put_user_x(1,__ret_pu,(char)(x),ptr); break;		\
-	case 2:  __put_user_x(2,__ret_pu,(short)(x),ptr); break;	\
-	case 4:  __put_user_x(4,__ret_pu,(int)(x),ptr); break;		\
-	default: __put_user_x(X,__ret_pu,x,ptr); break;			\
+#define put_user(x,ptr)									\
+({	int __ret_pu;									\
+	switch(sizeof (*(ptr))) {							\
+	case 1:  __put_user_x(1,__ret_pu,(__typeof__(*(ptr)))(x),ptr); break;		\
+	case 2:  __put_user_x(2,__ret_pu,(__typeof__(*(ptr)))(x),ptr); break;		\
+	case 4:  __put_user_x(4,__ret_pu,(__typeof__(*(ptr)))(x),ptr); break;		\
+	default: __put_user_x(X,__ret_pu,x,ptr); break;					\
+	}										\
+	__ret_pu;									\
+})
+
+#define __get_user(x,ptr) \
+  __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
+#define __put_user(x,ptr) \
+  __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
+
+#define __put_user_nocheck(x,ptr,size)			\
+({							\
+	long __pu_err;					\
+	__put_user_size((x),(ptr),(size),__pu_err);	\
+	__pu_err;					\
+})
+
+#define __put_user_size(x,ptr,size,retval)				\
+do {									\
+	retval = 0;							\
+	switch (size) {							\
+	  case 1: __put_user_asm(x,ptr,retval,"b","b","iq"); break;	\
+	  case 2: __put_user_asm(x,ptr,retval,"w","w","ir"); break;	\
+	  case 4: __put_user_asm(x,ptr,retval,"l","","ir"); break;	\
+	  default: __put_user_bad();					\
 	}								\
-	__ret_pu;							\
+} while (0)
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct *)(x))
+
+/*
+ * Tell gcc we read from memory instead of writing: this is because
+ * we do not write to any memory gcc knows about, so there are no
+ * aliasing issues.
+ */
+#define __put_user_asm(x, addr, err, itype, rtype, ltype)	\
+	__asm__ __volatile__(					\
+		"1:	mov"itype" %"rtype"1,%2\n"		\
+		"2:\n"						\
+		".section .fixup,\"ax\"\n"			\
+		"3:	movl %3,%0\n"				\
+		"	jmp 2b\n"				\
+		".previous\n"					\
+		".section __ex_table,\"a\"\n"			\
+		"	.align 4\n"				\
+		"	.long 1b,3b\n"				\
+		".previous"					\
+		: "=r"(err)					\
+		: ltype (x), "m"(__m(addr)), "i"(-EFAULT), "0"(err))
+
+
+#define __get_user_nocheck(x,ptr,size)				\
+({								\
+	long __gu_err, __gu_val;				\
+	__get_user_size(__gu_val,(ptr),(size),__gu_err);	\
+	(x) = (__typeof__(*(ptr)))__gu_val;			\
+	__gu_err;						\
 })
 
-#define __get_user(x,ptr) get_user(x,ptr)
-#define __put_user(x,ptr) put_user(x,ptr)
+extern long __get_user_bad(void);
+
+#define __get_user_size(x,ptr,size,retval)				\
+do {									\
+	retval = 0;							\
+	switch (size) {							\
+	  case 1: __get_user_asm(x,ptr,retval,"b","b","=q"); break;	\
+	  case 2: __get_user_asm(x,ptr,retval,"w","w","=r"); break;	\
+	  case 4: __get_user_asm(x,ptr,retval,"l","","=r"); break;	\
+	  default: (x) = __get_user_bad();				\
+	}								\
+} while (0)
+
+#define __get_user_asm(x, addr, err, itype, rtype, ltype)	\
+	__asm__ __volatile__(					\
+		"1:	mov"itype" %2,%"rtype"1\n"		\
+		"2:\n"						\
+		".section .fixup,\"ax\"\n"			\
+		"3:	movl %3,%0\n"				\
+		"	xor"itype" %"rtype"1,%"rtype"1\n"	\
+		"	jmp 2b\n"				\
+		".previous\n"					\
+		".section __ex_table,\"a\"\n"			\
+		"	.align 4\n"				\
+		"	.long 1b,3b\n"				\
+		".previous"					\
+		: "=r"(err), ltype (x)				\
+		: "m"(__m(addr)), "i"(-EFAULT), "0"(err))
 
 /*
  * The "xxx_ret" versions return constant specified in third argument, if