From 13b89711a2ddc389efb2a220e2f34ab8ff47021b Mon Sep 17 00:00:00 2001 From: Mathias Krause Date: Sun, 10 Apr 2016 12:52:28 +0200 Subject: [PATCH] packet: fix heap info leak in PACKET_DIAG_MCLIST sock_diag interface commit 309cf37fe2a781279b7675d4bb7173198e532867 upstream. Because we miss to wipe the remainder of i->addr[] in packet_mc_add(), pdiag_put_mclist() leaks uninitialized heap bytes via the PACKET_DIAG_MCLIST netlink attribute. Fix this by explicitly memset(0)ing the remaining bytes in i->addr[]. Fixes: eea68e2f1a00 ("packet: Report socket mclist info via diag module") Signed-off-by: Mathias Krause Cc: Eric W. Biederman Cc: Pavel Emelyanov Acked-by: Pavel Emelyanov Signed-off-by: David S. Miller Signed-off-by: Willy Tarreau --- net/packet/af_packet.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 39fa33969b09..2d454a235e84 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2997,6 +2997,7 @@ static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) i->ifindex = mreq->mr_ifindex; i->alen = mreq->mr_alen; memcpy(i->addr, mreq->mr_address, i->alen); + memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen); i->count = 1; i->next = po->mclist; po->mclist = i; -- 2.20.1