--- zzzz-none-000/linux-3.10.107/arch/s390/include/asm/checksum.h 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/arch/s390/include/asm/checksum.h 2021-02-04 17:41:59.000000000 +0000 @@ -44,22 +44,15 @@ * here even more important to align src and dst on a 32-bit (or even * better 64-bit) boundary * - * Copy from userspace and compute checksum. If we catch an exception - * then zero the rest of the buffer. + * Copy from userspace and compute checksum. */ static inline __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr) { - int missing; - - missing = copy_from_user(dst, src, len); - if (missing) { - memset(dst + len - missing, 0, missing); + if (unlikely(copy_from_user(dst, src, len))) *err_ptr = -EFAULT; - } - return csum_partial(dst, len, sum); }