From c6404122cb18f1fbd2a6dc85ab687f6fa2e454cf Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 16 Apr 2018 08:29:43 -0700 Subject: [PATCH] tipc: fix possible crash in __tipc_nl_net_set() syzbot reported a crash in __tipc_nl_net_set() caused by NULL dereference. We need to check that both TIPC_NLA_NET_NODEID and TIPC_NLA_NET_NODEID_W1 are present. We also need to make sure userland provided u64 attributes. Fixes: d50ccc2d3909 ("tipc: add 128-bit node identifier") Signed-off-by: Eric Dumazet Cc: Jon Maloy Cc: Ying Xue Reported-by: syzbot Signed-off-by: David S. Miller --- net/tipc/net.c | 2 ++ net/tipc/netlink.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/net/tipc/net.c b/net/tipc/net.c index 856f9e9..4fbaa04 100644 --- a/net/tipc/net.c +++ b/net/tipc/net.c @@ -252,6 +252,8 @@ int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info) u64 *w0 = (u64 *)&node_id[0]; u64 *w1 = (u64 *)&node_id[8]; + if (!attrs[TIPC_NLA_NET_NODEID_W1]) + return -EINVAL; *w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]); *w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]); tipc_net_init(net, node_id, 0); diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c index d4e0bbe..6ff2254 100644 --- a/net/tipc/netlink.c +++ b/net/tipc/netlink.c @@ -81,6 +81,8 @@ const struct nla_policy tipc_nl_net_policy[TIPC_NLA_NET_MAX + 1] = { [TIPC_NLA_NET_UNSPEC] = { .type = NLA_UNSPEC }, [TIPC_NLA_NET_ID] = { .type = NLA_U32 }, [TIPC_NLA_NET_ADDR] = { .type = NLA_U32 }, + [TIPC_NLA_NET_NODEID] = { .type = NLA_U64 }, + [TIPC_NLA_NET_NODEID_W1] = { .type = NLA_U64 }, }; const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = { -- 2.7.4