From aa81700cf2326e288c9ca1fe7b544039617f1fc2 Mon Sep 17 00:00:00 2001 From: Davide Caratti Date: Mon, 6 Apr 2020 11:38:29 +0200 Subject: [PATCH] macsec: fix NULL dereference in macsec_upd_offload() macsec_upd_offload() gets the value of MACSEC_OFFLOAD_ATTR_TYPE without checking its presence in the request message, and this causes a NULL dereference. Fix it rejecting any configuration that does not include this attribute. Reported-and-tested-by: syzbot+7022ab7c383875c17eff@syzkaller.appspotmail.com Fixes: dcb780fb2795 ("net: macsec: add nla support for changing the offloading selection") Signed-off-by: Davide Caratti Signed-off-by: David S. Miller --- drivers/net/macsec.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index da82d7f16a09..0d580d81d910 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -2594,6 +2594,9 @@ static int macsec_upd_offload(struct sk_buff *skb, struct genl_info *info) return PTR_ERR(dev); macsec = macsec_priv(dev); + if (!tb_offload[MACSEC_OFFLOAD_ATTR_TYPE]) + return -EINVAL; + offload = nla_get_u8(tb_offload[MACSEC_OFFLOAD_ATTR_TYPE]); if (macsec->offload == offload) return 0; -- 2.20.1