From 473ac55c5e036a73455bfbf5bf7b7bffeac4fa3d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 7 Apr 2018 13:42:37 -0700 Subject: [PATCH] netlink: fix uninit-value in netlink_sendmsg commit 6091f09c2f79730d895149bcfe3d66140288cd0e upstream. syzbot reported : BUG: KMSAN: uninit-value in ffs arch/x86/include/asm/bitops.h:432 [inline] BUG: KMSAN: uninit-value in netlink_sendmsg+0xb26/0x1310 net/netlink/af_netlink.c:1851 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/netlink/af_netlink.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 1e97b8d9a159..15e6e7b9fd2b 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1795,6 +1795,8 @@ static int netlink_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) if (msg->msg_namelen) { err = -EINVAL; + if (msg->msg_namelen < sizeof(struct sockaddr_nl)) + goto out; if (addr->nl_family != AF_NETLINK) goto out; dst_portid = addr->nl_pid; -- 2.20.1