From: David Clark <david.clark@datasoft.com>
Date: Wed, 20 Mar 2013 00:06:35 +0000 (-0700)
Subject: Fix valgrind warning (jump on unitialized value) due to missing ioctl wrapper
X-Git-Tag: libpcap-1.5.0~61
X-Git-Url: https://git.tcpdump.org/libpcap/commitdiff_plain/76b1c8f6a8255759a24983a26960d61ab03af20c

Fix valgrind warning (jump on unitialized value) due to missing ioctl wrapper

Valgrind doesn't have a wrapper for the SIOCETHTOOL ioctl call yet. This
is causing every program that uses libpcap and valgrind to produce some
false warnings because it thinks eval.data was never initialized. A harmless
fix is to just set eval.data to 0 instead of leaving it unitialized before
the SIOCETHTOOL ioctl call sets it.
---

diff --git a/pcap-linux.c b/pcap-linux.c
index 6a4d8aad..201f2aad 100644
--- a/pcap-linux.c
+++ b/pcap-linux.c
@@ -4934,6 +4934,7 @@ iface_ethtool_ioctl(pcap_t *handle, int cmd, const char *cmdname)
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, handle->opt.source, sizeof(ifr.ifr_name));
 	eval.cmd = cmd;
+	eval.data = 0;
 	ifr.ifr_data = (caddr_t)&eval;
 	if (ioctl(handle->fd, SIOCETHTOOL, &ifr) == -1) {
 		if (errno == EOPNOTSUPP || errno == EINVAL) {