From 7880287981b60a6808f39f297bb66936e8bdf57a Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Fri, 23 Mar 2018 13:49:02 +0100 Subject: [PATCH] netlink: make sure nladdr has correct size in netlink_connect() KMSAN reports use of uninitialized memory in the case when |alen| is smaller than sizeof(struct sockaddr_nl), and therefore |nladdr| isn't fully copied from the userspace. Signed-off-by: Alexander Potapenko Fixes: 1da177e4c3f41524 ("Linux-2.6.12-rc2") Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- net/netlink/af_netlink.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 07e8478068f0a1..70c455341243b2 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1085,6 +1085,9 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr, if (addr->sa_family != AF_NETLINK) return -EINVAL; + if (alen < sizeof(struct sockaddr_nl)) + return -EINVAL; + if ((nladdr->nl_groups || nladdr->nl_pid) && !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND)) return -EPERM;