[PATCH] unistr.c: Fix use-after-free in 'ntfs_uppercase_mbs'. If 'utf8_to_unicode' throws an error due to an invalid UTF-8 sequence, then 'n' will be less than 0 and the loop will terminate without storing anything in '*t'. After the loop the uppercase string's allocation is freed, however after it is freed it is unconditionally accessed through '*t', which points into the freed allocation, for the purpose of NULL- terminating the string. This leads to a use-after-free. Fixed by only NULL-terminating the string when no error has been thrown.
Thanks for Jeffrey Bencteux for reporting this issue: https://github.com/tuxera/ntfs-3g/issues/84
