Make sure malloc worked before accessing the mem in chan_modem.c (bug 2704)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@4054 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_modem.c b/channels/chan_modem.c
index 677edd4..a911f41 100755 (executable)
--- a/channels/chan_modem.c
+++ b/channels/chan_modem.c
@@ -712,8 +712,8 @@ static struct ast_modem_pvt *mkif(char *iface)
 #endif
        
        tmp = malloc(sizeof(struct ast_modem_pvt));
-       memset(tmp, 0, sizeof(struct ast_modem_pvt));
        if (tmp) {
+               memset(tmp, 0, sizeof(struct ast_modem_pvt));
                tmp->fd = open(iface, O_RDWR | O_NONBLOCK);
                if (tmp->fd < 0) {
                        ast_log(LOG_WARNING, "Unable to open '%s'\n", iface);