net: fix infoleak in rtnetlink

Orabug: 25308083

[ Upstream commit 5f8e44741f9f216e33736ea4ec65ca9ac03036e6 ]

The stack object “map” has a total size of 32 bytes. Its last 4
bytes are padding generated by compiler. These padding bytes are
not initialized and sent out via “nla_put”.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
(cherry picked from commit 9a9390bcf56680c487a8e4c89c813a48bfedc4b6)
Signed-off-by: Dhaval Giani <dhaval.giani@oracle.com>

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index fe95cb704aaa0a08f358032ee88ca9c39b8e1331..a8804c46f23222ec83f99643c6fe120875878e65 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1070,14 +1070,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                goto nla_put_failure;
 
        if (1) {
-               struct rtnl_link_ifmap map = {
-                       .mem_start   = dev->mem_start,
-                       .mem_end     = dev->mem_end,
-                       .base_addr   = dev->base_addr,
-                       .irq         = dev->irq,
-                       .dma         = dev->dma,
-                       .port        = dev->if_port,
-               };
+               struct rtnl_link_ifmap map;
+
+               memset(&map, 0, sizeof(map));
+               map.mem_start   = dev->mem_start;
+               map.mem_end     = dev->mem_end;
+               map.base_addr   = dev->base_addr;
+               map.irq         = dev->irq;
+               map.dma         = dev->dma;
+               map.port        = dev->if_port;
+
                if (nla_put(skb, IFLA_MAP, sizeof(map), &map))
                        goto nla_put_failure;
        }