From 1a7fca63cd405fc77a9c9ce9291792f2a7d222a4 Mon Sep 17 00:00:00 2001 From: Benjamin LaHaise Date: Mon, 1 May 2017 09:58:40 -0400 Subject: [PATCH] flower: check unused bits in MPLS fields Since several of the the netlink attributes used to configure the flower classifier's MPLS TC, BOS and Label fields have additional bits which are unused, check those bits to ensure that they are actually 0 as suggested by Jamal. Signed-off-by: Benjamin LaHaise Cc: David Miller Cc: Jamal Hadi Salim Cc: Simon Horman Cc: Jakub Kicinski Cc: Jiri Pirko Signed-off-by: David S. Miller --- net/sched/cls_flower.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 3ecf07666df3..ca526c0881bd 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -439,29 +439,39 @@ static void fl_set_key_val(struct nlattr **tb, memcpy(mask, nla_data(tb[mask_type]), len); } -static void fl_set_key_mpls(struct nlattr **tb, - struct flow_dissector_key_mpls *key_val, - struct flow_dissector_key_mpls *key_mask) +static int fl_set_key_mpls(struct nlattr **tb, + struct flow_dissector_key_mpls *key_val, + struct flow_dissector_key_mpls *key_mask) { if (tb[TCA_FLOWER_KEY_MPLS_TTL]) { key_val->mpls_ttl = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_TTL]); key_mask->mpls_ttl = MPLS_TTL_MASK; } if (tb[TCA_FLOWER_KEY_MPLS_BOS]) { - key_val->mpls_bos = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_BOS]); + u8 bos = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_BOS]); + + if (bos & ~MPLS_BOS_MASK) + return -EINVAL; + key_val->mpls_bos = bos; key_mask->mpls_bos = MPLS_BOS_MASK; } if (tb[TCA_FLOWER_KEY_MPLS_TC]) { - key_val->mpls_tc = - nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_TC]) & MPLS_TC_MASK; + u8 tc = nla_get_u8(tb[TCA_FLOWER_KEY_MPLS_TC]); + + if (tc & ~MPLS_TC_MASK) + return -EINVAL; + key_val->mpls_tc = tc; key_mask->mpls_tc = MPLS_TC_MASK; } if (tb[TCA_FLOWER_KEY_MPLS_LABEL]) { - key_val->mpls_label = - nla_get_u32(tb[TCA_FLOWER_KEY_MPLS_LABEL]) & - MPLS_LABEL_MASK; + u32 label = nla_get_u32(tb[TCA_FLOWER_KEY_MPLS_LABEL]); + + if (label & ~MPLS_LABEL_MASK) + return -EINVAL; + key_val->mpls_label = label; key_mask->mpls_label = MPLS_LABEL_MASK; } + return 0; } static void fl_set_key_vlan(struct nlattr **tb, @@ -622,7 +632,9 @@ static int fl_set_key(struct net *net, struct nlattr **tb, sizeof(key->icmp.code)); } else if (key->basic.n_proto == htons(ETH_P_MPLS_UC) || key->basic.n_proto == htons(ETH_P_MPLS_MC)) { - fl_set_key_mpls(tb, &key->mpls, &mask->mpls); + ret = fl_set_key_mpls(tb, &key->mpls, &mask->mpls); + if (ret) + return ret; } else if (key->basic.n_proto == htons(ETH_P_ARP) || key->basic.n_proto == htons(ETH_P_RARP)) { fl_set_key_val(tb, &key->arp.sip, TCA_FLOWER_KEY_ARP_SIP, -- GitLab