From: David Tardon <dtardon@redhat.com>
Date: Wed, 24 Mar 2021 13:45:02 +0000 (+0100)
Subject: local-addresses: fix use of uninitialized value
X-Git-Tag: v248-2~24
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d2f4a9488ce0847da754614706fadefbca9ed2a4;p=thirdparty%2Fsystemd.git

local-addresses: fix use of uninitialized value

This can happen if ifi fails to be read from the netlink message and the
error is ENODATA.

Fixes the following valgrind message when running netstat:

==164141== Conditional jump or move depends on uninitialised value(s)
==164141==    at 0x524AE60: address_compare (local-addresses.c:29)
==164141==    by 0x48BCC78: msort_with_tmp.part.0 (msort.c:105)
==164141==    by 0x48BC9E4: msort_with_tmp (msort.c:45)
==164141==    by 0x48BC9E4: msort_with_tmp.part.0 (msort.c:53)
==164141==    by 0x48BCF85: msort_with_tmp (msort.c:45)
==164141==    by 0x48BCF85: qsort_r (msort.c:297)
==164141==    by 0x52500FC: UnknownInlinedFun (sort-util.h:47)
==164141==    by 0x52500FC: local_gateways.constprop.0 (local-addresses.c:310)
==164141==    by 0x5251C05: _nss_myhostname_gethostbyaddr2_r (nss-myhostname.c:456)
==164141==    by 0x5252006: _nss_myhostname_gethostbyaddr_r (nss-myhostname.c:500)
==164141==    by 0x498E7FE: gethostbyaddr_r@@GLIBC_2.2.5 (getXXbyYY_r.c:274)
==164141==    by 0x498E560: gethostbyaddr (getXXbyYY.c:135)
==164141==    by 0x121353: INET_rresolve.constprop.0 (inet.c:212)
==164141==    by 0x1135B9: INET_sprint (inet.c:261)
==164141==    by 0x121BFC: addr_do_one.constprop.0.isra.0 (netstat.c:1156)
---

diff --git a/src/shared/local-addresses.c b/src/shared/local-addresses.c
index 2c860f76d5d..1de890f1421 100644
--- a/src/shared/local-addresses.c
+++ b/src/shared/local-addresses.c
@@ -204,7 +204,7 @@ int local_gateways(sd_netlink *context, int ifindex, int af, struct local_addres
                 union in_addr_union gateway;
                 uint16_t type;
                 unsigned char dst_len, src_len, table;
-                uint32_t ifi, metric = 0;
+                uint32_t ifi = 0, metric = 0;
                 size_t rta_len;
                 int family;
                 RouteVia via;