[systemd-devel] [PATCH 5/5] strv: multiple cleanups

[Peeters Simon]

2014/1/5 Zbigniew Jędrzejewski-Szmek <zbyszek at in.waw.pl>:
> Looks great, except for one issue:
>
> On Sat, Jan 04, 2014 at 02:35:27AM +0100, Simon Peeters wrote:
>> @@ -1865,14 +1863,11 @@ finish:
>>                          watchdog_close(false);
>>
>>                          /* Tell the binary how often to ping */
>> -                        snprintf(e, sizeof(e), "WATCHDOG_USEC=%llu", (unsigned long long) arg_shutdown_watchdog);
>> -                        char_array_0(e);
>> +                        asprintf(&e, "WATCHDOG_USEC=%llu", (unsigned long long) arg_shutdown_watchdog);
>>
>> -                        env_block = strv_append(environ, e);
>> -                } else {
>> -                        env_block = strv_copy(environ);
>> +                        strv_push(&env_block, e);
> Should there be oom handling here?

there wasn't any in place, since this is shutdown code, I think we
just need to avoid segfaulting on oom.
but indeed, asprintf() doesn't set e to null on oom, so that should be:
if (asprintf(&e, "WATCHDOG_USEC="USEC_FMT, arg_shutdown_watchdog) < 0)
  e = NULL;

and then it is equivalently oom safe as before, which means in worst
case passing a NULL env to the shutdown binary.