diff options
Diffstat (limited to 'arch/x86/lib/usercopy_32.c')
-rw-r--r-- | arch/x86/lib/usercopy_32.c | 41 |
1 files changed, 0 insertions, 41 deletions
diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c index 883b216c60b2..1781b2f950e2 100644 --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -95,47 +95,6 @@ __clear_user(void __user *to, unsigned long n) } EXPORT_SYMBOL(__clear_user); -/** - * strnlen_user: - Get the size of a string in user space. - * @s: The string to measure. - * @n: The maximum valid length - * - * Get the size of a NUL-terminated string in user space. - * - * Returns the size of the string INCLUDING the terminating NUL. - * On exception, returns 0. - * If the string is too long, returns a value greater than @n. - */ -long strnlen_user(const char __user *s, long n) -{ - unsigned long mask = -__addr_ok(s); - unsigned long res, tmp; - - might_fault(); - - __asm__ __volatile__( - " testl %0, %0\n" - " jz 3f\n" - " andl %0,%%ecx\n" - "0: repne; scasb\n" - " setne %%al\n" - " subl %%ecx,%0\n" - " addl %0,%%eax\n" - "1:\n" - ".section .fixup,\"ax\"\n" - "2: xorl %%eax,%%eax\n" - " jmp 1b\n" - "3: movb $1,%%al\n" - " jmp 1b\n" - ".previous\n" - _ASM_EXTABLE(0b,2b) - :"=&r" (n), "=&D" (s), "=&a" (res), "=&c" (tmp) - :"0" (n), "1" (s), "2" (0), "3" (mask) - :"cc"); - return res & mask; -} -EXPORT_SYMBOL(strnlen_user); - #ifdef CONFIG_X86_INTEL_USERCOPY static unsigned long __copy_user_intel(void __user *to, const void *from, unsigned long size) |