[SSSD-users] Re: [External] Re: 'automount -m' segfaults when using sssd

[Alexey Tikhonov]

On Wed, Jan 25, 2023 at 10:40 PM Alexey Tikhonov <atikhono(a)redhat.com&gt;
wrote:

>  On Wed, Jan 25, 2023 at 5:34 PM Prentice Bisbal <pbisbal(a)pppl.gov&gt; wrote:
>
> > (difficult to confirm without coredump/backtraces).
> >
> > Would a stack trace of automount or the sssd daemon be sufficient?
> >
>  No, I meant backtrace from a coredump. Maybe `ltrace` can help also, but I
>  doubt `strace` is handy here.
>
> >
> > I tried to compile the trivial reproducer from the GitHub Issue you
> > linked to, but I'm getting an error when I try to compile it:
> >
> > # gcc sssd_tester.c -o sssd_tester -lsss_nss_idmap -lpthread -ldl
> > sssd_tester.c: In function ‘thread’:
> > sssd_tester.c:12:5: warning: implicit declaration of function
> > ‘sss_getpwnam’; did you mean ‘getpwnam’? [-Wimplicit-function-declaration]
> >    12 |     sss_getpwnam("test", &res, buff, sizeof(buff),
> &errnop);
> >       |     ^~~~~~~~~~~~
> >       |     getpwnam
> >
> > It looks like sss_getpwnam isn't defined in any of the header files in
> > /usr/include, or I just can't find what package provides it.
> >
>  Link against `/lib64/libnss_sss.so.2`:
>  
Sorry, no need, of course:
sss_getpwnam = dlsym(h, "_nss_sss_getpwnam_r");

I just accidentally cut off a few beginning lines of a reproducer, while
pasting to github: includes and `sss_getpwnam` variable (pointer to
function) declaration.

Something like:
```
typedef int (*fp)(const char *name, struct passwd *result,
                 char *buffer, size_t buflen, int *errnop);

fp sss_getpwnam;
```




>  ```
>  $ nm -D /lib64/libnss_sss.so.2 | grep sss_getpwnam
>  0000000000005f10 T _nss_sss_getpwnam_r@@EXPORTED
>  ```
>  (no need to link against `sss_nss_idmap`)
>
>  But why? It won't help to assure you face the same issue.
>
>
>
>
>
>