Fix crash during destruction of second channel when variable set with setvar.

The setvar line in chan_dahdi.conf is shared among all the channels, so make
sure to only free the resources only when the last channel is destroyed.

(closes issue #15899)
Reported by: tzafrir

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@222298 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_dahdi.c b/channels/chan_dahdi.c
index 8a43bacad13293cba7935785bae96b6c173bdd30..0af7d7d4be1fecd13eb11fbdbaf995c3bee10d4f 100644 (file)
--- a/channels/chan_dahdi.c
+++ b/channels/chan_dahdi.c
@@ -4881,8 +4881,9 @@ static void destroy_dahdi_pvt(struct dahdi_pvt *pvt)
                ast_smdi_interface_unref(p->smdi_iface);
        if (p->mwi_event_sub)
                ast_event_unsubscribe(p->mwi_event_sub);
-       if (p->vars)
+       if (p->vars && iflist && !iflist->next) {
                ast_variables_destroy(p->vars);
+       }
        ast_mutex_destroy(&p->lock);
        dahdi_close_sub(p, SUB_REAL);
        if (p->owner)