diff options
Diffstat (limited to 'arch/s390/lib/uaccess_pt.c')
| -rw-r--r-- | arch/s390/lib/uaccess_pt.c | 34 |
1 files changed, 18 insertions, 16 deletions
diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c index c1aaf22c326b..304e07086ab3 100644 --- a/arch/s390/lib/uaccess_pt.c +++ b/arch/s390/lib/uaccess_pt.c @@ -202,27 +202,29 @@ fault: static size_t strncpy_from_user_pt(size_t count, const char __user *src, char *dst) { - size_t n = strnlen_user_pt(count, src); + size_t done, len, offset, len_str; if (unlikely(!count)) return 0; - if (!n) - return -EFAULT; - if (n > count) - n = count; if (segment_eq(get_fs(), KERNEL_DS)) { - memcpy(dst, (const char __kernel __force *) src, n); - if (dst[n-1] == '\0') - return n-1; - else - return n; + len = strnlen((const char __kernel __force *) src, count) + 1; + if (len > count) + len = count; + memcpy(dst, (const char __kernel __force *) src, len); + return (dst[len - 1] == '\0') ? len - 1 : len; } - if (__user_copy_pt((unsigned long) src, dst, n, 0)) - return -EFAULT; - if (dst[n-1] == '\0') - return n-1; - else - return n; + done = 0; + do { + offset = (size_t)src & ~PAGE_MASK; + len = min(count - done, PAGE_SIZE - offset); + if (__user_copy_pt((unsigned long) src, dst, len, 0)) + return -EFAULT; + len_str = strnlen(dst, len); + done += len_str; + src += len_str; + dst += len_str; + } while ((len_str == len) && (done < count)); + return done; } static size_t copy_in_user_pt(size_t n, void __user *to, |