From c7a42eb49212f93a800560662d17d5293960d3c3 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Fri, 23 Aug 2019 19:33:03 +0800 Subject: [PATCH] net: ipv6: fix listify ip6_rcv_finish in case of forwarding We need a similar fix for ipv6 as Commit 0761680d5215 ("net: ipv4: fix listify ip_rcv_finish in case of forwarding") does for ipv4. This issue can be reprocuded by syzbot since Commit 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs") on net-next. The call trace was: kernel BUG at include/linux/skbuff.h:2225! RIP: 0010:__skb_pull include/linux/skbuff.h:2225 [inline] RIP: 0010:skb_pull+0xea/0x110 net/core/skbuff.c:1902 Call Trace: sctp_inq_pop+0x2f1/0xd80 net/sctp/inqueue.c:202 sctp_endpoint_bh_rcv+0x184/0x8d0 net/sctp/endpointola.c:385 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80 sctp_rcv+0x2807/0x3590 net/sctp/input.c:256 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1049 ip6_protocol_deliver_rcu+0x2fe/0x1660 net/ipv6/ip6_input.c:397 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:438 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:447 dst_input include/net/dst.h:442 [inline] ip6_sublist_rcv_finish+0x98/0x1e0 net/ipv6/ip6_input.c:84 ip6_list_rcv_finish net/ipv6/ip6_input.c:118 [inline] ip6_sublist_rcv+0x80c/0xcf0 net/ipv6/ip6_input.c:282 ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:316 __netif_receive_skb_list_ptype net/core/dev.c:5049 [inline] __netif_receive_skb_list_core+0x5fc/0x9d0 net/core/dev.c:5097 __netif_receive_skb_list net/core/dev.c:5149 [inline] netif_receive_skb_list_internal+0x7eb/0xe60 net/core/dev.c:5244 gro_normal_list.part.0+0x1e/0xb0 net/core/dev.c:5757 gro_normal_list net/core/dev.c:5755 [inline] gro_normal_one net/core/dev.c:5769 [inline] napi_frags_finish net/core/dev.c:5782 [inline] napi_gro_frags+0xa6a/0xea0 net/core/dev.c:5855 tun_get_user+0x2e98/0x3fa0 drivers/net/tun.c:1974 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2020 Fixes: d8269e2cbf90 ("net: ipv6: listify ipv6_rcv() and ip6_rcv_finish()") Fixes: 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs") Reported-by: syzbot+eb349eeee854e389c36d@syzkaller.appspotmail.com Reported-by: syzbot+4a0643a653ac375612d1@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Edward Cree Signed-off-by: David S. Miller --- net/ipv6/ip6_input.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index fa014d5f1732..d432d0011c16 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -80,8 +80,10 @@ static void ip6_sublist_rcv_finish(struct list_head *head) { struct sk_buff *skb, *next; - list_for_each_entry_safe(skb, next, head, list) + list_for_each_entry_safe(skb, next, head, list) { + skb_list_del_init(skb); dst_input(skb); + } } static void ip6_list_rcv_finish(struct net *net, struct sock *sk, -- 2.30.2