kerberos 5 login (krb 5.1.2-5)

[Tom Yu]

>>>>> "jerry" == Jerry Heyman <jerry at scosco.raleigh.tivoli.com> writes:

jerry> In article <ah74fd$5v4$1 at tivnews.tivoli.com>,
jerry>  jerry at scosco.raleigh.tivoli.com (Jerry Heyman) writes:
>> In article <tslvg7evwi6.fsf at konishi-polis.mit.edu>,
>> hartmans at mit.edu (Sam Hartman) writes:
>>> I'd step through login in a debugger and see where it hangs.  If you
>>> cannot do that, then start inserting debugging print statements and
>>> binary search where it hangs.
>> 
>> 
>> #ifdef __hpux
>> strcpy(utmp_id, cp);
>> #else
>> if (len > 2 && *(cp - 1) != '/')
>> sprintf(utmp_id, "k%s", cp - 1);
>> else
>> sprintf(utmp_id, "k0%s", cp);
>> #endif
>> strncpy(utx.ut_id, utmp_id, sizeof(utx.ut_id));

jerry> Hate to follow up my own post, but the above strncpy resolves
jerry> to 
jerry>       strncpy (utx.ut_id, utmp_id, 0)

jerry> And the quite a bit more is being copied than anticipated.  The
jerry> modification I made is:

jerry>      strncpy(utx.ut_id, utmp_id, sizeof(utmp_id));

That seems wrong.  Why is sizeof(utx.ut_id) zero?  It shouldn't be.
In any case, using sizeof(utmp_id) can result in bad things if
sizeof(utx.ut_id) is less than sizeof(utmp_id).

---Tom