virBufferCurrentContent might be get a NULL string, and then without checking it, this can cause a segfault as strlen expects a string != NULL. Use virBufferCheckError to check error before calling strlen. --- src/util/virsystemd.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/util/virsystemd.c b/src/util/virsystemd.c index ceb1c1a..cfc4bdb 100644 --- a/src/util/virsystemd.c +++ b/src/util/virsystemd.c @@ -135,6 +135,8 @@ virSystemdAppendValidMachineName(virBufferPtr buf, bool skip_dot = false; for (; *name; name++) { + if (virBufferCheckError(buf) < 0) + break; if (strlen(virBufferCurrentContent(buf)) >= 64) break; -- 2.8.3