diff options
Diffstat (limited to 'arch/x86/include/asm/uaccess.h')
| -rw-r--r-- | arch/x86/include/asm/uaccess.h | 97 |
1 files changed, 49 insertions, 48 deletions
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index b5e58cc0c5e7..a77445d1b034 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -77,9 +77,6 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un /** * access_ok: - Checks if a user space pointer is valid - * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that - * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe - * to write to a block, it is always safe to read from it. * @addr: User space pointer to start of block to check * @size: Size of block to check * @@ -95,7 +92,7 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un * checks that the pointer is in the user space range - after calling * this function, memory access functions may still return -EFAULT. */ -#define access_ok(type, addr, size) \ +#define access_ok(addr, size) \ ({ \ WARN_ON_IN_IRQ(); \ likely(!__range_not_ok(addr, size, user_addr_max())); \ @@ -189,19 +186,14 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) #ifdef CONFIG_X86_32 -#define __put_user_asm_u64(x, addr, err, errret) \ - asm volatile("\n" \ - "1: movl %%eax,0(%2)\n" \ - "2: movl %%edx,4(%2)\n" \ - "3:" \ - ".section .fixup,\"ax\"\n" \ - "4: movl %3,%0\n" \ - " jmp 3b\n" \ - ".previous\n" \ - _ASM_EXTABLE_UA(1b, 4b) \ - _ASM_EXTABLE_UA(2b, 4b) \ - : "=r" (err) \ - : "A" (x), "r" (addr), "i" (errret), "0" (err)) +#define __put_user_goto_u64(x, addr, label) \ + asm_volatile_goto("\n" \ + "1: movl %%eax,0(%1)\n" \ + "2: movl %%edx,4(%1)\n" \ + _ASM_EXTABLE_UA(1b, %l2) \ + _ASM_EXTABLE_UA(2b, %l2) \ + : : "A" (x), "r" (addr) \ + : : label) #define __put_user_asm_ex_u64(x, addr) \ asm volatile("\n" \ @@ -216,8 +208,8 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) asm volatile("call __put_user_8" : "=a" (__ret_pu) \ : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx") #else -#define __put_user_asm_u64(x, ptr, retval, errret) \ - __put_user_asm(x, ptr, retval, "q", "", "er", errret) +#define __put_user_goto_u64(x, ptr, label) \ + __put_user_goto(x, ptr, "q", "", "er", label) #define __put_user_asm_ex_u64(x, addr) \ __put_user_asm_ex(x, addr, "q", "", "er") #define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu) @@ -278,23 +270,21 @@ extern void __put_user_8(void); __builtin_expect(__ret_pu, 0); \ }) -#define __put_user_size(x, ptr, size, retval, errret) \ +#define __put_user_size(x, ptr, size, label) \ do { \ - retval = 0; \ __chk_user_ptr(ptr); \ switch (size) { \ case 1: \ - __put_user_asm(x, ptr, retval, "b", "b", "iq", errret); \ + __put_user_goto(x, ptr, "b", "b", "iq", label); \ break; \ case 2: \ - __put_user_asm(x, ptr, retval, "w", "w", "ir", errret); \ + __put_user_goto(x, ptr, "w", "w", "ir", label); \ break; \ case 4: \ - __put_user_asm(x, ptr, retval, "l", "k", "ir", errret); \ + __put_user_goto(x, ptr, "l", "k", "ir", label); \ break; \ case 8: \ - __put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval, \ - errret); \ + __put_user_goto_u64((__typeof__(*ptr))(x), ptr, label); \ break; \ default: \ __put_user_bad(); \ @@ -439,9 +429,12 @@ do { \ #define __put_user_nocheck(x, ptr, size) \ ({ \ - int __pu_err; \ + __label__ __pu_label; \ + int __pu_err = -EFAULT; \ __uaccess_begin(); \ - __put_user_size((x), (ptr), (size), __pu_err, -EFAULT); \ + __put_user_size((x), (ptr), (size), __pu_label); \ + __pu_err = 0; \ +__pu_label: \ __uaccess_end(); \ __builtin_expect(__pu_err, 0); \ }) @@ -466,17 +459,23 @@ struct __large_struct { unsigned long buf[100]; }; * 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, errret) \ - asm volatile("\n" \ - "1: mov"itype" %"rtype"1,%2\n" \ - "2:\n" \ - ".section .fixup,\"ax\"\n" \ - "3: mov %3,%0\n" \ - " jmp 2b\n" \ - ".previous\n" \ - _ASM_EXTABLE_UA(1b, 3b) \ - : "=r"(err) \ - : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err)) +#define __put_user_goto(x, addr, itype, rtype, ltype, label) \ + asm_volatile_goto("\n" \ + "1: mov"itype" %"rtype"0,%1\n" \ + _ASM_EXTABLE_UA(1b, %l2) \ + : : ltype(x), "m" (__m(addr)) \ + : : label) + +#define __put_user_failed(x, addr, itype, rtype, ltype, errret) \ + ({ __label__ __puflab; \ + int __pufret = errret; \ + __put_user_goto(x,addr,itype,rtype,ltype,__puflab); \ + __pufret = 0; \ + __puflab: __pufret; }) + +#define __put_user_asm(x, addr, retval, itype, rtype, ltype, errret) do { \ + retval = __put_user_failed(x, addr, itype, rtype, ltype, errret); \ +} while (0) #define __put_user_asm_ex(x, addr, itype, rtype, ltype) \ asm volatile("1: mov"itype" %"rtype"0,%1\n" \ @@ -670,7 +669,7 @@ extern void __cmpxchg_wrong_size(void) #define user_atomic_cmpxchg_inatomic(uval, ptr, old, new) \ ({ \ - access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) ? \ + access_ok((ptr), sizeof(*(ptr))) ? \ __user_atomic_cmpxchg_inatomic((uval), (ptr), \ (old), (new), sizeof(*(ptr))) : \ -EFAULT; \ @@ -708,16 +707,18 @@ extern struct movsl_mask { * checking before using them, but you have to surround them with the * user_access_begin/end() pair. */ -#define user_access_begin() __uaccess_begin() +static __must_check inline bool user_access_begin(const void __user *ptr, size_t len) +{ + if (unlikely(!access_ok(ptr,len))) + return 0; + __uaccess_begin(); + return 1; +} +#define user_access_begin(a,b) user_access_begin(a,b) #define user_access_end() __uaccess_end() -#define unsafe_put_user(x, ptr, err_label) \ -do { \ - int __pu_err; \ - __typeof__(*(ptr)) __pu_val = (x); \ - __put_user_size(__pu_val, (ptr), sizeof(*(ptr)), __pu_err, -EFAULT); \ - if (unlikely(__pu_err)) goto err_label; \ -} while (0) +#define unsafe_put_user(x, ptr, label) \ + __put_user_size((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label) #define unsafe_get_user(x, ptr, err_label) \ do { \ |