[PATCH] fix a kernel infoleak in x25 module

From: Kangjie Lu
Date: Sun May 08 2016 - 12:07:16 EST


Stack object "dte_facilities" is allocated in x25_rx_call_request(),
which is supposed to be initialized in x25_negotiate_facilities.
However, 5 fields (8 bytes in total) are not initialized. This
object is then copied to userland via copy_to_user, thus infoleak
occurs.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxxxxx>
---
net/x25/x25_facilities.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/x25/x25_facilities.c b/net/x25/x25_facilities.c
index 2844031..a1c30c6 100644
--- a/net/x25/x25_facilities.c
+++ b/net/x25/x25_facilities.c
@@ -278,6 +278,7 @@ int x25_negotiate_facilities(struct sk_buff *skb, struct sock *sk,

memset(&theirs, 0, sizeof(theirs));
memcpy(new, ours, sizeof(*new));
+ memset(dte, 0, sizeof(*dte));

len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
if (len < 0)
--
1.9.1