From b8e68fce6f0e5ad0e04f5d8c9bd4606e93ce461d Mon Sep 17 00:00:00 2001 From: Menglong Dong Date: Sat, 5 Feb 2022 15:47:36 +0800 Subject: [PATCH] net: ipv4: use kfree_skb_reason() in ip_rcv_finish_core() [ Upstream commit c1f166d1f7eef212096a98b22f5acf92f9af353d ] Replace kfree_skb() with kfree_skb_reason() in ip_rcv_finish_core(), following drop reasons are introduced: SKB_DROP_REASON_IP_RPFILTER SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST Signed-off-by: Menglong Dong Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/linux/skbuff.h | 9 +++++++++ include/trace/events/skb.h | 3 +++ net/ipv4/ip_input.c | 14 ++++++++++---- 3 files changed, 22 insertions(+), 4 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 514fb80..cbd719e 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -327,6 +327,15 @@ enum skb_drop_reason { * IP header (see * IPSTATS_MIB_INHDRERRORS) */ + SKB_DROP_REASON_IP_RPFILTER, /* IP rpfilter validate failed. + * see the document for rp_filter + * in ip-sysctl.rst for more + * information + */ + SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST, /* destination address of L2 + * is multicast, but L3 is + * unicast. + */ SKB_DROP_REASON_MAX, }; diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h index f2b1778..485a1d3 100644 --- a/include/trace/events/skb.h +++ b/include/trace/events/skb.h @@ -20,6 +20,9 @@ EM(SKB_DROP_REASON_OTHERHOST, OTHERHOST) \ EM(SKB_DROP_REASON_IP_CSUM, IP_CSUM) \ EM(SKB_DROP_REASON_IP_INHDR, IP_INHDR) \ + EM(SKB_DROP_REASON_IP_RPFILTER, IP_RPFILTER) \ + EM(SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST, \ + UNICAST_IN_L2_MULTICAST) \ EMe(SKB_DROP_REASON_MAX, MAX) #undef EM diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 7be18de..d5222c0 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -318,8 +318,10 @@ static int ip_rcv_finish_core(struct net *net, struct sock *sk, { const struct iphdr *iph = ip_hdr(skb); int (*edemux)(struct sk_buff *skb); + int err, drop_reason; struct rtable *rt; - int err; + + drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; if (ip_can_use_hint(skb, iph, hint)) { err = ip_route_use_hint(skb, iph->daddr, iph->saddr, iph->tos, @@ -396,19 +398,23 @@ static int ip_rcv_finish_core(struct net *net, struct sock *sk, * so-called "hole-196" attack) so do it for both. */ if (in_dev && - IN_DEV_ORCONF(in_dev, DROP_UNICAST_IN_L2_MULTICAST)) + IN_DEV_ORCONF(in_dev, DROP_UNICAST_IN_L2_MULTICAST)) { + drop_reason = SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST; goto drop; + } } return NET_RX_SUCCESS; drop: - kfree_skb(skb); + kfree_skb_reason(skb, drop_reason); return NET_RX_DROP; drop_error: - if (err == -EXDEV) + if (err == -EXDEV) { + drop_reason = SKB_DROP_REASON_IP_RPFILTER; __NET_INC_STATS(net, LINUX_MIB_IPRPFILTER); + } goto drop; } -- 2.7.4