linux/net/ipv4
Dong Chenchen 55a43bae08 net: Remove acked SYN flag from packet in the transmit queue correctly
[ Upstream commit f99cd56230 ]

syzkaller report:

 kernel BUG at net/core/skbuff.c:3452!
 invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.7.0-rc4-00009-gbee0e7762ad2-dirty #135
 RIP: 0010:skb_copy_and_csum_bits (net/core/skbuff.c:3452)
 Call Trace:
 icmp_glue_bits (net/ipv4/icmp.c:357)
 __ip_append_data.isra.0 (net/ipv4/ip_output.c:1165)
 ip_append_data (net/ipv4/ip_output.c:1362 net/ipv4/ip_output.c:1341)
 icmp_push_reply (net/ipv4/icmp.c:370)
 __icmp_send (./include/net/route.h:252 net/ipv4/icmp.c:772)
 ip_fragment.constprop.0 (./include/linux/skbuff.h:1234 net/ipv4/ip_output.c:592 net/ipv4/ip_output.c:577)
 __ip_finish_output (net/ipv4/ip_output.c:311 net/ipv4/ip_output.c:295)
 ip_output (net/ipv4/ip_output.c:427)
 __ip_queue_xmit (net/ipv4/ip_output.c:535)
 __tcp_transmit_skb (net/ipv4/tcp_output.c:1462)
 __tcp_retransmit_skb (net/ipv4/tcp_output.c:3387)
 tcp_retransmit_skb (net/ipv4/tcp_output.c:3404)
 tcp_retransmit_timer (net/ipv4/tcp_timer.c:604)
 tcp_write_timer (./include/linux/spinlock.h:391 net/ipv4/tcp_timer.c:716)

The panic issue was trigered by tcp simultaneous initiation.
The initiation process is as follows:

      TCP A                                            TCP B

  1.  CLOSED                                           CLOSED

  2.  SYN-SENT     --> <SEQ=100><CTL=SYN>              ...

  3.  SYN-RECEIVED <-- <SEQ=300><CTL=SYN>              <-- SYN-SENT

  4.               ... <SEQ=100><CTL=SYN>              --> SYN-RECEIVED

  5.  SYN-RECEIVED --> <SEQ=100><ACK=301><CTL=SYN,ACK> ...

  // TCP B: not send challenge ack for ack limit or packet loss
  // TCP A: close
	tcp_close
	   tcp_send_fin
              if (!tskb && tcp_under_memory_pressure(sk))
                  tskb = skb_rb_last(&sk->tcp_rtx_queue); //pick SYN_ACK packet
           TCP_SKB_CB(tskb)->tcp_flags |= TCPHDR_FIN;  // set FIN flag

  6.  FIN_WAIT_1  --> <SEQ=100><ACK=301><END_SEQ=102><CTL=SYN,FIN,ACK> ...

  // TCP B: send challenge ack to SYN_FIN_ACK

  7.               ... <SEQ=301><ACK=101><CTL=ACK>   <-- SYN-RECEIVED //challenge ack

  // TCP A:  <SND.UNA=101>

  8.  FIN_WAIT_1 --> <SEQ=101><ACK=301><END_SEQ=102><CTL=SYN,FIN,ACK> ... // retransmit panic

	__tcp_retransmit_skb  //skb->len=0
	    tcp_trim_head
		len = tp->snd_una - TCP_SKB_CB(skb)->seq // len=101-100
		    __pskb_trim_head
			skb->data_len -= len // skb->len=-1, wrap around
	    ... ...
	    ip_fragment
		icmp_glue_bits //BUG_ON

If we use tcp_trim_head() to remove acked SYN from packet that contains data
or other flags, skb->len will be incorrectly decremented. We can remove SYN
flag that has been acked from rtx_queue earlier than tcp_trim_head(), which
can fix the problem mentioned above.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Co-developed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com>
Link: https://lore.kernel.org/r/20231210020200.1539875-1-dongchenchen2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2023-12-20 17:00:18 +01:00
..
bpfilter net: Revert "net: optimize the sockptr_t for unified kernel/user address spaces" 2020-08-10 12:06:44 -07:00
netfilter netfilter: tproxy: fix deadlock due to missing BH disable 2023-03-17 08:50:25 +01:00
af_inet.c tcp: allow again tcp_disconnect() when threads are waiting 2023-10-25 12:03:12 +02:00
ah4.c xfrm: ah: add extack to ah_init_state, ah6_init_state 2022-09-29 07:17:59 +02:00
arp.c neighbour: annotate lockless accesses to n->nud_state 2023-10-10 22:00:42 +02:00
bpf_tcp_ca.c bpf: Use 0 instead of NOT_INIT for btf_struct_access() writes 2022-09-10 17:27:32 -07:00
cipso_ipv4.c cipso: Fix data-races around sysctl. 2022-07-08 12:10:33 +01:00
datagram.c ipv4: fix data-races around inet->inet_id 2023-08-30 16:11:02 +02:00
devinet.c net: ipv4: fix one memleak in __inet_del_ifa() 2023-09-19 12:28:08 +02:00
esp4.c net: ipv4: fix return value check in esp_remove_trailer 2023-10-25 12:03:06 +02:00
esp4_offload.c xfrm: Linearize the skb after offloading if needed. 2023-06-28 11:12:29 +02:00
fib_frontend.c ipv4: Fix incorrect table ID in IOCTL path 2023-03-22 13:33:50 +01:00
fib_lookup.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-02-17 11:44:20 -08:00
fib_notifier.c net: ipv4: remove superfluous header files from fib_notifier.c 2021-09-28 17:32:56 -07:00
fib_rules.c ipv4: remove unnecessary type castings 2022-04-30 15:12:58 +01:00
fib_semantics.c ipv4/fib: send notify when delete source address routes 2023-10-25 12:03:11 +02:00
fib_trie.c ipv4/fib: send notify when delete source address routes 2023-10-25 12:03:11 +02:00
fou.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
gre_demux.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
gre_offload.c net: gro: skb_gro_header helper function 2022-08-25 10:33:21 +02:00
icmp.c icmp: guard against too small mtu 2023-04-13 16:55:21 +02:00
igmp.c ipv4: igmp: fix refcnt uaf issue when receiving igmp query packet 2023-12-08 08:51:17 +01:00
inet_connection_sock.c tcp: allow again tcp_disconnect() when threads are waiting 2023-10-25 12:03:12 +02:00
inet_diag.c net: annotate data-races around sk->sk_mark 2023-08-11 12:08:14 +02:00
inet_fragment.c ipv4: remove unnecessary type castings 2022-04-30 15:12:58 +01:00
inet_hashtables.c net: set SOCK_RCU_FREE before inserting socket into hashtable 2023-11-28 17:07:04 +00:00
inet_timewait_sock.c Revert "tcp: avoid the lookup process failing to get sk in ehash table" 2023-07-27 08:50:45 +02:00
inetpeer.c inetpeer: Fix data-races around sysctl. 2022-07-08 12:10:33 +01:00
ip_forward.c ip: Fix data-races around sysctl_ip_fwd_update_priority. 2022-07-15 11:49:55 +01:00
ip_fragment.c net: ip: Handle delivery_time in ip defrag 2022-03-03 14:38:48 +00:00
ip_gre.c ipv4: ip_gre: Avoid skb_pull() failure in ipgre_xmit() 2023-12-13 18:39:09 +01:00
ip_input.c ipv4: ignore dst hint for multipath routes 2023-09-19 12:28:01 +02:00
ip_options.c ipv4: drop fragmentation code from ip_options_build() 2022-01-29 17:53:07 +00:00
ip_output.c neighbour: switch to standard rcu, instead of rcu_bh 2023-10-10 22:00:42 +02:00
ip_sockglue.c net: annotate data-races around sk->sk_priority 2023-08-11 12:08:15 +02:00
ip_tunnel.c net: tunnels: annotate lockless accesses to dev->needed_headroom 2023-03-22 13:33:46 +01:00
ip_tunnel_core.c tunnels: fix kasan splat when generating ipv4 pmtu error 2023-08-16 18:27:27 +02:00
ip_vti.c ip_vti: fix potential slab-use-after-free in decode_session6 2023-08-23 17:52:32 +02:00
ipcomp.c xfrm: ipcomp: add extack to ipcomp{4,6}_init_state 2022-09-29 07:18:00 +02:00
ipconfig.c Driver core / kernfs changes for 6.0-rc1 2022-08-04 11:31:20 -07:00
ipip.c net: Add helper function to parse netlink msg of ip_tunnel_parm 2022-10-03 07:59:06 +01:00
ipmr.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-09-22 13:02:10 -07:00
ipmr_base.c ipmr: adopt rcu_read_lock() in mr_dump() 2022-06-24 11:34:38 +01:00
Kconfig tcp: configurable source port perturb table size 2022-11-16 13:02:04 +00:00
Makefile bpf: Clean up sockmap related Kconfigs 2021-02-26 12:28:03 -08:00
metrics.c ipv4: prevent potential spectre v1 gadget in ip_metrics_convert() 2023-02-01 08:34:45 +01:00
netfilter.c netfilter: Use l3mdev flow key when re-routing mangled packets 2022-05-16 13:03:29 +02:00
netlink.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
nexthop.c neighbour: switch to standard rcu, instead of rcu_bh 2023-10-10 22:00:42 +02:00
ping.c ping: Fix potentail NULL deref for /proc/net/icmp. 2023-04-13 16:55:24 +02:00
proc.c tcp: Don't allocate tcp_death_row outside of struct netns_ipv4. 2022-09-20 10:21:49 -07:00
protocol.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
raw.c net: annotate data-races around sk->sk_priority 2023-08-11 12:08:15 +02:00
raw_diag.c raw: Fix NULL deref in raw_get_next(). 2023-04-13 16:55:23 +02:00
route.c ipv4: Correct/silence an endian warning in __ip_do_redirect 2023-12-03 07:32:07 +01:00
syncookies.c tcp: fix cookie_init_timestamp() overflows 2023-11-20 11:51:54 +01:00
sysctl_net_ipv4.c tcp: enforce receive buffer memory limits by allowing the tcp window to shrink 2023-10-19 23:08:54 +02:00
tcp.c tcp: fix mid stream window clamp. 2023-12-13 18:39:09 +01:00
tcp_bbr.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
tcp_bic.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_bpf.c tcp_bpf: properly release resources on error paths 2023-10-25 12:03:13 +02:00
tcp_cdg.c Random number generator fixes for Linux 6.1-rc1. 2022-10-16 15:27:07 -07:00
tcp_cong.c tcp: Add tracepoint for tcp_set_ca_state 2022-04-07 20:33:15 -07:00
tcp_cubic.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
tcp_dctcp.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
tcp_dctcp.h tcp: refactor DCTCP ECN ACK handling 2018-10-10 22:26:00 -07:00
tcp_diag.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
tcp_fastopen.c tcp: annotate data-races around fastopenq.max_qlen 2023-07-27 08:50:49 +02:00
tcp_highspeed.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_htcp.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_hybla.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_illinois.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_input.c tcp: do not accept ACK of bytes we never sent 2023-12-13 18:39:11 +01:00
tcp_ipv4.c tcp: check mptcp-level constraints for backlog coalescing 2023-10-25 12:03:04 +02:00
tcp_lp.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_metrics.c tcp_metrics: do not create an entry from tcp_init_metrics() 2023-11-20 11:51:53 +01:00
tcp_minisocks.c tcp: annotate data-races around tcp_rsk(req)->ts_recent 2023-07-27 08:50:45 +02:00
tcp_nv.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_offload.c tcp: gso: really support BIG TCP 2023-06-14 11:15:20 +02:00
tcp_output.c net: Remove acked SYN flag from packet in the transmit queue correctly 2023-12-20 17:00:18 +01:00
tcp_rate.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-04-28 13:02:01 -07:00
tcp_recovery.c tcp: fix excessive TLP and RACK timeouts from HZ rounding 2023-10-25 12:03:06 +02:00
tcp_scalable.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_timer.c net: tcp: fix unexcepted socket die when snd_wnd is 0 2023-09-13 09:42:32 +02:00
tcp_ulp.c net/ulp: use consistent error code when blocking ULP 2023-01-24 07:24:43 +01:00
tcp_vegas.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_vegas.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tcp_veno.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_westwood.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_yeah.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tunnel4.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
udp.c udp: add missing WRITE_ONCE() around up->encap_rcv 2023-11-20 11:51:52 +01:00
udp_bpf.c bpf, sockmap: Fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser() 2023-03-17 08:50:24 +01:00
udp_diag.c net: Use nlmsg_unicast() instead of netlink_unicast() 2021-07-13 09:28:29 -07:00
udp_impl.h net: remove noblock parameter from recvmsg() entities 2022-04-12 15:00:25 +02:00
udp_offload.c gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers 2021-11-24 17:21:42 -08:00
udp_tunnel_core.c net/tunnel: wait until all sk_user_data reader finish before releasing the sock 2022-12-31 13:32:27 +01:00
udp_tunnel_nic.c udp_tunnel: Fix end of loop test in udp_tunnel_nic_unregister() 2022-02-23 12:35:00 +00:00
udp_tunnel_stub.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udplite.c udplite: Fix NULL pointer dereference in __sk_mem_raise_allocated(). 2023-05-30 14:03:20 +01:00
xfrm4_input.c xfrm: fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets 2023-06-28 11:12:28 +02:00
xfrm4_output.c xfrm: fix unused variable warning if CONFIG_NETFILTER=n 2020-05-11 15:12:27 +02:00
xfrm4_policy.c net: rename reference+tracking helpers 2022-06-09 21:52:55 -07:00
xfrm4_protocol.c net: xfrm: unexport __init-annotated xfrm4_protocol_init() 2022-06-08 10:10:13 -07:00
xfrm4_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_tunnel.c xfrm: tunnel: add extack to ipip_init_state, xfrm6_tunnel_init_state 2022-09-29 07:18:00 +02:00