diff options
| -rw-r--r-- | arch/x86/include/asm/thread_info.h | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/uaccess.h | 103 | ||||
| -rw-r--r-- | arch/x86/mm/extable.c | 6 |
3 files changed, 110 insertions, 0 deletions
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 9878964..3f90aeb 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -40,6 +40,7 @@ struct thread_info { */ __u8 supervisor_stack[0]; #endif + int uaccess_err; }; #define INIT_THREAD_INFO(tsk) \ diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 69d2757..0ec6de4 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -199,12 +199,22 @@ extern int __get_user_bad(void); : "=r" (err) \ : "A" (x), "r" (addr), "i" (-EFAULT), "0" (err)) +#define __put_user_asm_ex_u64(x, addr) \ + asm volatile("1: movl %%eax,0(%1)\n" \ + "2: movl %%edx,4(%1)\n" \ + "3:\n" \ + _ASM_EXTABLE(1b, 2b - 1b) \ + _ASM_EXTABLE(2b, 3b - 2b) \ + : : "A" (x), "r" (addr)) + #define __put_user_x8(x, ptr, __ret_pu) \ 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) \ __put_user_asm(x, ptr, retval, "q", "", "Zr", -EFAULT) +#define __put_user_asm_ex_u64(x, addr) \ + __put_user_asm_ex(x, addr, "q", "", "Zr") #define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu) #endif @@ -286,6 +296,27 @@ do { \ } \ } while (0) +#define __put_user_size_ex(x, ptr, size) \ +do { \ + __chk_user_ptr(ptr); \ + switch (size) { \ + case 1: \ + __put_user_asm_ex(x, ptr, "b", "b", "iq"); \ + break; \ + case 2: \ + __put_user_asm_ex(x, ptr, "w", "w", "ir"); \ + break; \ + case 4: \ + __put_user_asm_ex(x, ptr, "l", "k", "ir"); \ + break; \ + case 8: \ + __put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr); \ + break; \ + default: \ + __put_user_bad(); \ + } \ +} while (0) + #else #define __put_user_size(x, ptr, size, retval, errret) \ @@ -311,9 +342,12 @@ do { \ #ifdef CONFIG_X86_32 #define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad() +#define __get_user_asm_ex_u64(x, ptr) (x) = __get_user_bad() #else #define __get_user_asm_u64(x, ptr, retval, errret) \ __get_user_asm(x, ptr, retval, "q", "", "=r", errret) +#define __get_user_asm_ex_u64(x, ptr) \ + __get_user_asm_ex(x, ptr, "q", "", "=r") #endif #define __get_user_size(x, ptr, size, retval, errret) \ @@ -350,6 +384,33 @@ do { \ : "=r" (err), ltype(x) \ : "m" (__m(addr)), "i" (errret), "0" (err)) +#define __get_user_size_ex(x, ptr, size) \ +do { \ + __chk_user_ptr(ptr); \ + switch (size) { \ + case 1: \ + __get_user_asm_ex(x, ptr, "b", "b", "=q"); \ + break; \ + case 2: \ + __get_user_asm_ex(x, ptr, "w", "w", "=r"); \ + break; \ + case 4: \ + __get_user_asm_ex(x, ptr, "l", "k", "=r"); \ + break; \ + case 8: \ + __get_user_asm_ex_u64(x, ptr); \ + break; \ + default: \ + (x) = __get_user_bad(); \ + } \ +} while (0) + +#define __get_user_asm_ex(x, addr, itype, rtype, ltype) \ + asm volatile("1: mov"itype" %1,%"rtype"0\n" \ + "2:\n" \ + _ASM_EXTABLE(1b, 2b - 1b) \ + : ltype(x) : "m" (__m(addr))) + #define __put_user_nocheck(x, ptr, size) \ ({ \ int __pu_err; \ @@ -385,6 +446,26 @@ struct __large_struct { unsigned long buf[100]; }; _ASM_EXTABLE(1b, 3b) \ : "=r"(err) \ : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err)) + +#define __put_user_asm_ex(x, addr, itype, rtype, ltype) \ + asm volatile("1: mov"itype" %"rtype"0,%1\n" \ + "2:\n" \ + _ASM_EXTABLE(1b, 2b - 1b) \ + : : ltype(x), "m" (__m(addr))) + +/* + * uaccess_try and catch + */ +#define uaccess_try do { \ + int prev_err = current_thread_info()->uaccess_err; \ + current_thread_info()->uaccess_err = 0; \ + barrier(); + +#define uaccess_catch(err) \ + (err) |= current_thread_info()->uaccess_err; \ + current_thread_info()->uaccess_err = prev_err; \ +} while (0) + /** * __get_user: - Get a simple variable from user space, with less checking. * @x: Variable to store result. @@ -408,6 +489,7 @@ struct __large_struct { unsigned long buf[100]; }; #define __get_user(x, ptr) \ __get_user_nocheck((x), (ptr), sizeof(*(ptr))) + /** * __put_user: - Write a simple value into user space, with less checking. * @x: Value to copy to user space. @@ -435,6 +517,27 @@ struct __large_struct { unsigned long buf[100]; }; #define __put_user_unaligned __put_user /* + * {get|put}_user_try and catch + * + * get_user_try { + * get_user_ex(...); + * } get_user_catch(err) + */ +#define get_user_try uaccess_try +#define get_user_catch(err) uaccess_catch(err) +#define put_user_try uaccess_try +#define put_user_catch(err) uaccess_catch(err) + +#define get_user_ex(x, ptr) do { \ + unsigned long __gue_val; \ + __get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr)))); \ + (x) = (__force __typeof__(*(ptr)))__gue_val; \ +} while (0) + +#define put_user_ex(x, ptr) \ + __put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) + +/* * movsl can be slow when source and dest are not both 8-byte aligned */ #ifdef CONFIG_X86_INTEL_USERCOPY diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 7e8db53..61b41ca 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -23,6 +23,12 @@ int fixup_exception(struct pt_regs *regs) fixup = search_exception_tables(regs->ip); if (fixup) { + /* If fixup is less than 16, it means uaccess error */ + if (fixup->fixup < 16) { + current_thread_info()->uaccess_err = -EFAULT; + regs->ip += fixup->fixup; + return 1; + } regs->ip = fixup->fixup; return 1; } |
