Merge tag 'v4.4.41' into linux-linaro-lsk-v4.4

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / include / asm / uaccess.h

diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index f973bdce8410a6dfca02066afd17864861b78ff1..c3d445b42351e1a529d94c4ba44e9c4d37544821 100644 (file)
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -36,11 +36,11 @@
 #define VERIFY_WRITE 1
 
 /*
- * The exception table consists of pairs of addresses: the first is the
- * address of an instruction that is allowed to fault, and the second is
- * the address at which the program should continue.  No registers are
- * modified, so it is entirely up to the continuation code to figure out
- * what to do.
+ * The exception table consists of pairs of relative offsets: the first
+ * is the relative offset to an instruction that is allowed to fault,
+ * and the second is the relative offset at which the program should
+ * continue. No registers are modified, so it is entirely up to the
+ * continuation code to figure out what to do.
  *
  * All the routines below use bits of fixup code that are out of line
  * with the main instruction path.  This means when everything is well,
@@ -50,9 +50,11 @@
 
 struct exception_table_entry
 {
-       unsigned long insn, fixup;
+       int insn, fixup;
 };
 
+#define ARCH_HAS_RELATIVE_EXTABLE
+
 extern int fixup_exception(struct pt_regs *regs);
 
 #define KERNEL_DS      (-1UL)
@@ -115,6 +117,12 @@ static inline void set_fs(mm_segment_t fs)
 #define access_ok(type, addr, size)    __range_ok(addr, size)
 #define user_addr_max                  get_fs
 
+#define _ASM_EXTABLE(from, to)                                         \
+       "       .pushsection    __ex_table, \"a\"\n"                    \
+       "       .align          3\n"                                    \
+       "       .long           (" #from " - .), (" #to " - .)\n"       \
+       "       .popsection\n"
+
 /*
  * The "__xxx" versions of the user access functions do not verify the address
  * space - it must have been done previously with a separate "access_ok()"
@@ -134,10 +142,7 @@ static inline void set_fs(mm_segment_t fs)
        "       mov     %1, #0\n"                                       \
        "       b       2b\n"                                           \
        "       .previous\n"                                            \
-       "       .section __ex_table,\"a\"\n"                            \
-       "       .align  3\n"                                            \
-       "       .quad   1b, 3b\n"                                       \
-       "       .previous"                                              \
+       _ASM_EXTABLE(1b, 3b)                                            \
        : "+r" (err), "=&r" (x)                                         \
        : "r" (addr), "i" (-EFAULT))
 
@@ -145,7 +150,7 @@ static inline void set_fs(mm_segment_t fs)
 do {                                                                   \
        unsigned long __gu_val;                                         \
        __chk_user_ptr(ptr);                                            \
-       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN,        \
+       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_ALT_PAN_NOT_UAO,\
                        CONFIG_ARM64_PAN));                             \
        switch (sizeof(*(ptr))) {                                       \
        case 1:                                                         \
@@ -168,7 +173,7 @@ do {                                                                        \
                BUILD_BUG();                                            \
        }                                                               \
        (x) = (__force __typeof__(*(ptr)))__gu_val;                     \
-       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN,        \
+       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_ALT_PAN_NOT_UAO,\
                        CONFIG_ARM64_PAN));                             \
 } while (0)
 
@@ -206,10 +211,7 @@ do {                                                                       \
        "3:     mov     %w0, %3\n"                                      \
        "       b       2b\n"                                           \
        "       .previous\n"                                            \
-       "       .section __ex_table,\"a\"\n"                            \
-       "       .align  3\n"                                            \
-       "       .quad   1b, 3b\n"                                       \
-       "       .previous"                                              \
+       _ASM_EXTABLE(1b, 3b)                                            \
        : "+r" (err)                                                    \
        : "r" (x), "r" (addr), "i" (-EFAULT))
 
@@ -217,7 +219,7 @@ do {                                                                        \
 do {                                                                   \
        __typeof__(*(ptr)) __pu_val = (x);                              \
        __chk_user_ptr(ptr);                                            \
-       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN,        \
+       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_ALT_PAN_NOT_UAO,\
                        CONFIG_ARM64_PAN));                             \
        switch (sizeof(*(ptr))) {                                       \
        case 1:                                                         \
@@ -239,7 +241,7 @@ do {                                                                        \
        default:                                                        \
                BUILD_BUG();                                            \
        }                                                               \
-       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN,        \
+       asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_ALT_PAN_NOT_UAO,\
                        CONFIG_ARM64_PAN));                             \
 } while (0)
 
@@ -267,24 +269,39 @@ do {                                                                      \
                -EFAULT;                                                \
 })
 
-extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
-extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
+extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n);
+extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n);
 extern unsigned long __must_check __copy_in_user(void __user *to, const void __user *from, unsigned long n);
 extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
 
+static inline unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+       check_object_size(to, n, false);
+       return __arch_copy_from_user(to, from, n);
+}
+
+static inline unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+       check_object_size(from, n, true);
+       return __arch_copy_to_user(to, from, n);
+}
+
 static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
 {
-       if (access_ok(VERIFY_READ, from, n))
-               n = __copy_from_user(to, from, n);
-       else /* security hole - plug it */
+       if (access_ok(VERIFY_READ, from, n)) {
+               check_object_size(to, n, false);
+               n = __arch_copy_from_user(to, from, n);
+       } else /* security hole - plug it */
                memset(to, 0, n);
        return n;
 }
 
 static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
 {
-       if (access_ok(VERIFY_WRITE, to, n))
-               n = __copy_to_user(to, from, n);
+       if (access_ok(VERIFY_WRITE, to, n)) {
+               check_object_size(from, n, true);
+               n = __arch_copy_to_user(to, from, n);
+       }
        return n;
 }