Message ID | 20220124131538.1453657-3-imagedong@tencent.com |
---|---|
State | Handled Elsewhere |
Delegated to: | Pablo Neira |
Headers | show |
Series | net: use kfree_skb_reason() for ip/udp packet receive | expand |
On 1/24/22 6:15 AM, menglong8.dong@gmail.com wrote: > @@ -478,7 +483,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) > IPSTATS_MIB_NOECTPKTS + (iph->tos & INET_ECN_MASK), > max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); > > - if (!pskb_may_pull(skb, iph->ihl*4)) > + if (!pskb_may_pull(skb, iph->ihl * 4)) unrelated cleanup > goto inhdr_error; > > iph = ip_hdr(skb); > @@ -490,7 +495,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) > if (skb->len < len) { > __IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS); > goto drop; > - } else if (len < (iph->ihl*4)) > + } else if (len < (iph->ihl * 4)) ditto > goto inhdr_error; > > /* Our transport medium may have padded the buffer out. Now we know it
On Wed, Jan 26, 2022 at 10:10 AM David Ahern <dsahern@gmail.com> wrote: > > On 1/24/22 6:15 AM, menglong8.dong@gmail.com wrote: > > @@ -478,7 +483,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) > > IPSTATS_MIB_NOECTPKTS + (iph->tos & INET_ECN_MASK), > > max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); > > > > - if (!pskb_may_pull(skb, iph->ihl*4)) > > + if (!pskb_may_pull(skb, iph->ihl * 4)) > > unrelated cleanup > Haha, you got me :/ > > goto inhdr_error; > > > > iph = ip_hdr(skb); > > @@ -490,7 +495,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) > > if (skb->len < len) { > > __IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS); > > goto drop; > > - } else if (len < (iph->ihl*4)) > > + } else if (len < (iph->ihl * 4)) > > ditto > > > goto inhdr_error; > > > > /* Our transport medium may have padded the buffer out. Now we know it >
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 1bcd690b8ae1..f3028028b83e 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -321,6 +321,9 @@ enum skb_drop_reason { SKB_DROP_REASON_TCP_FILTER, SKB_DROP_REASON_UDP_CSUM, SKB_DROP_REASON_NETFILTER_DROP, + SKB_DROP_REASON_OTHERHOST, + SKB_DROP_REASON_IP_CSUM, + SKB_DROP_REASON_IP_INHDR, SKB_DROP_REASON_MAX, }; diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h index beed7bb2bc0e..d1b0d9690e62 100644 --- a/include/trace/events/skb.h +++ b/include/trace/events/skb.h @@ -17,6 +17,9 @@ EM(SKB_DROP_REASON_TCP_FILTER, TCP_FILTER) \ EM(SKB_DROP_REASON_UDP_CSUM, UDP_CSUM) \ EM(SKB_DROP_REASON_NETFILTER_DROP, NETFILTER_DROP) \ + EM(SKB_DROP_REASON_OTHERHOST, OTHERHOST) \ + EM(SKB_DROP_REASON_IP_CSUM, IP_CSUM) \ + EM(SKB_DROP_REASON_IP_INHDR, IP_INHDR) \ EMe(SKB_DROP_REASON_MAX, MAX) #undef EM diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 3a025c011971..ab9bee4bbf0a 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -436,13 +436,18 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) { const struct iphdr *iph; + int drop_reason; u32 len; + drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; + /* When the interface is in promisc. mode, drop all the crap * that it receives, do not try to analyse it. */ - if (skb->pkt_type == PACKET_OTHERHOST) + if (skb->pkt_type == PACKET_OTHERHOST) { + drop_reason = SKB_DROP_REASON_OTHERHOST; goto drop; + } __IP_UPD_PO_STATS(net, IPSTATS_MIB_IN, skb->len); @@ -478,7 +483,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) IPSTATS_MIB_NOECTPKTS + (iph->tos & INET_ECN_MASK), max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); - if (!pskb_may_pull(skb, iph->ihl*4)) + if (!pskb_may_pull(skb, iph->ihl * 4)) goto inhdr_error; iph = ip_hdr(skb); @@ -490,7 +495,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) if (skb->len < len) { __IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS); goto drop; - } else if (len < (iph->ihl*4)) + } else if (len < (iph->ihl * 4)) goto inhdr_error; /* Our transport medium may have padded the buffer out. Now we know it @@ -516,11 +521,13 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) return skb; csum_error: + drop_reason = SKB_DROP_REASON_IP_CSUM; __IP_INC_STATS(net, IPSTATS_MIB_CSUMERRORS); inhdr_error: + drop_reason = drop_reason ?: SKB_DROP_REASON_IP_INHDR; __IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS); drop: - kfree_skb(skb); + kfree_skb_reason(skb, drop_reason); out: return NULL; }