I found two sssd_nss bugs pretty much by accident.
[PATCH 1/2] NSS: keep a pointer to body after body is reallocated
When a memory is reallocated with talloc_realloc, the original pointer
might be relocated elsewhere. The "fullname" pointer used to point to
the original location before realloc which led to use-after-free issues.
[PATCH 2/2] Use sized_string correctly in FQDN domains
We were using the structure itself instead of the string pointer, which
led to crashes when the domain was fully qualified.