Re: [LTP] [PATCH] Add tst_tmpdir_path() and tst_tmpdir_mkpath()

Andrea Cervesato via ltp
2024-07-24T09:01:45Z

Yeah this is the case.
The problem comes when tst_tmpdir_path() is used without giving .needs_tmpdir and the pointer to tmpdir is not initialised.

> On 24 Jul 2024, at 10:45, Cyril Hrubis <chrubis@suse.cz> wrote:
>
> ﻿Hi!
>>> I had a strange SEGFAULT when .needs_tmpdir is not defined. Are you sure the
>>> feature is correctly working in that case? TCONF should be expected in that
>>> case.
>>
>> Could you be more specific what is wrong? (failing test, what backtrace from gdb
>> outputs. Maybe run it both *with* and *without* set follow-fork-mode child, not
>> sure if the info will be in the library run or in the test fork run).
>>
>> I tested bind02.c, which is *without* .needs_tmpdir and it works. bind01.c is
>> *with* .needs_tmpdir and it also works. These are not modified by the merged
>> change (c5d95b6d3), thus I also tested chroot01.c (*without* .needs_tmpdir) and
>> it also works.
>>
>> Besides, openSUSE LTP testing of LTP syscalls with c5d95b6d3 [1] does not have
>> any new failures.
>
> I suppose that we need this, to have a TBROK message instead of SegFault
> if users call things out of order:
>
> diff --git a/lib/tst_tmpdir.c b/lib/tst_tmpdir.c
> index 1fb1bd698..bbb45dfa9 100644
> --- a/lib/tst_tmpdir.c
> +++ b/lib/tst_tmpdir.c
> @@ -358,6 +358,9 @@ char *tst_tmpdir_path(void)
> {
> static char *tmpdir;
>
> + if (!TESTDIR)
> + tst_brk(TBROK, ".needs_tmpdir must be set!");
> +
> if (tmpdir)
> return tmpdir;
>
> @@ -368,11 +371,16 @@ char *tst_tmpdir_path(void)
>
> char *tst_tmpdir_mkpath(const char *fmt, ...)
> {
> - size_t testdir_len = strlen(TESTDIR);
> - size_t path_len = testdir_len;
> + size_t testdir_len, path_len;
> va_list va, vac;
> char *ret;
>
> + if (!TESTDIR)
> + tst_brk(TBROK, ".needs_tmpdir must be set!");
> +
> + testdir_len = strlen(TESTDIR);
> + path_len = testdir_len;
> +
> va_start(va, fmt);
> va_copy(vac, va);
> path_len += vsnprintf(NULL, 0, fmt, va) + 2;
>
>
> --
> Cyril Hrubis
> chrubis@suse.cz

Andrea