[PATCH 3.16 280/305] tipc: fix an infoleak in tipc_nl_compat_link_dump

Ben Hutchings
2016-08-14T10:58:15Z

From: Kangjie Lu <kangjielu@gmail.com>

commit 5d2be1422e02ccd697ccfcd45c85b4a26e6178e2 upstream.

link_info.str is a char array of size 60. Memory after the NULL
byte is not initialized. Sending the whole object out can cause
a leak.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
[carnil: Backported to 3.16 (same as bwh did for 3.2): the unpadded strcpy() is
in tipc_node_get_links() and no nlattr is involved, so use strncpy()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -417,7 +417,8 @@ struct sk_buff *tipc_node_get_links(cons
continue;
link_info.dest = htonl(n_ptr->addr);
link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
- strcpy(link_info.str, n_ptr->links[i]->name);
+ strncpy(link_info.str, n_ptr->links[i]->name,
+ sizeof(link_info.str));
tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
&link_info, sizeof(link_info));
}