WSL2-Linux-Kernel/net/core
Liu Jian 124b7c7732 net: If sock is dead don't access sock's sk_wq in sk_stream_wait_memory
[ Upstream commit 3f8ef65af9 ]

Fixes the below NULL pointer dereference:

  [...]
  [   14.471200] Call Trace:
  [   14.471562]  <TASK>
  [   14.471882]  lock_acquire+0x245/0x2e0
  [   14.472416]  ? remove_wait_queue+0x12/0x50
  [   14.473014]  ? _raw_spin_lock_irqsave+0x17/0x50
  [   14.473681]  _raw_spin_lock_irqsave+0x3d/0x50
  [   14.474318]  ? remove_wait_queue+0x12/0x50
  [   14.474907]  remove_wait_queue+0x12/0x50
  [   14.475480]  sk_stream_wait_memory+0x20d/0x340
  [   14.476127]  ? do_wait_intr_irq+0x80/0x80
  [   14.476704]  do_tcp_sendpages+0x287/0x600
  [   14.477283]  tcp_bpf_push+0xab/0x260
  [   14.477817]  tcp_bpf_sendmsg_redir+0x297/0x500
  [   14.478461]  ? __local_bh_enable_ip+0x77/0xe0
  [   14.479096]  tcp_bpf_send_verdict+0x105/0x470
  [   14.479729]  tcp_bpf_sendmsg+0x318/0x4f0
  [   14.480311]  sock_sendmsg+0x2d/0x40
  [   14.480822]  ____sys_sendmsg+0x1b4/0x1c0
  [   14.481390]  ? copy_msghdr_from_user+0x62/0x80
  [   14.482048]  ___sys_sendmsg+0x78/0xb0
  [   14.482580]  ? vmf_insert_pfn_prot+0x91/0x150
  [   14.483215]  ? __do_fault+0x2a/0x1a0
  [   14.483738]  ? do_fault+0x15e/0x5d0
  [   14.484246]  ? __handle_mm_fault+0x56b/0x1040
  [   14.484874]  ? lock_is_held_type+0xdf/0x130
  [   14.485474]  ? find_held_lock+0x2d/0x90
  [   14.486046]  ? __sys_sendmsg+0x41/0x70
  [   14.486587]  __sys_sendmsg+0x41/0x70
  [   14.487105]  ? intel_pmu_drain_pebs_core+0x350/0x350
  [   14.487822]  do_syscall_64+0x34/0x80
  [   14.488345]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
  [...]

The test scenario has the following flow:

thread1                               thread2
-----------                           ---------------
 tcp_bpf_sendmsg
  tcp_bpf_send_verdict
   tcp_bpf_sendmsg_redir              sock_close
    tcp_bpf_push_locked                 __sock_release
     tcp_bpf_push                         //inet_release
      do_tcp_sendpages                    sock->ops->release
       sk_stream_wait_memory          	   // tcp_close
          sk_wait_event                      sk->sk_prot->close
           release_sock(__sk);
            ***
                                                lock_sock(sk);
                                                  __tcp_close
                                                    sock_orphan(sk)
                                                      sk->sk_wq  = NULL
                                                release_sock
            ****
           lock_sock(__sk);
          remove_wait_queue(sk_sleep(sk), &wait);
             sk_sleep(sk)
             //NULL pointer dereference
             &rcu_dereference_raw(sk->sk_wq)->wait

While waiting for memory in thread1, the socket is released with its wait
queue because thread2 has closed it. This caused by tcp_bpf_send_verdict
didn't increase the f_count of psock->sk_redir->sk_socket->file in thread1.

We should check if SOCK_DEAD flag is set on wakeup in sk_stream_wait_memory
before accessing the wait queue.

Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/bpf/20220823133755.314697-2-liujian56@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:35:37 +02:00
..
Makefile of: net: move of_net under net/ 2022-03-08 19:12:41 +01:00
bpf_sk_storage.c net: Fix data-races around sysctl_optmem_max. 2022-08-31 17:16:43 +02:00
datagram.c tcp: TX zerocopy should not sense pfmemalloc status 2022-09-15 11:30:05 +02:00
datagram.h
dev.c bpf: Don't redirect packets with invalid pkt_len 2022-09-05 10:30:07 +02:00
dev_addr_lists.c net: dev_addr_list: handle first address in __hw_addr_add_ex 2021-09-30 13:29:09 +01:00
dev_ioctl.c net: core: don't call SIOCBRADD/DELIF for non-bridge devices 2021-08-05 11:36:59 +01:00
devlink.c devlink: Fix use-after-free after a failed reload 2022-08-25 11:40:06 +02:00
drop_monitor.c net: skb: introduce kfree_skb_reason() 2022-07-29 17:25:15 +02:00
dst.c net: Remove redundant if statements 2021-08-05 13:27:50 +01:00
dst_cache.c wireguard: device: reset peer src endpoint when netns exits 2021-12-08 09:04:46 +01:00
failover.c
fib_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib_rules.c ipv6: fix memory leak in fib6_rule_suppress 2021-12-08 09:04:43 +01:00
filter.c net: Fix data-races around sysctl_optmem_max. 2022-08-31 17:16:43 +02:00
flow_dissector.c net: core: fix flow symmetric hash 2022-09-28 11:11:47 +02:00
flow_offload.c netfilter: nf_tables: bail out early if hardware offload is not supported 2022-06-14 18:36:17 +02:00
gen_estimator.c net_sched: gen_estimator: support large ewma log 2021-01-15 18:11:06 -08:00
gen_stats.c docs: networking: convert gen_stats.txt to ReST 2020-04-28 14:39:46 -07:00
gro_cells.c net: Fix data-races around netdev_max_backlog. 2022-08-31 17:16:42 +02:00
hwbm.c
link_watch.c net: Write lock dev_base_lock without disabling bottom halves. 2022-06-29 09:03:22 +02:00
lwt_bpf.c bpf, lwt: Fix crash when using bpf_skb_set_tunnel_key() from bpf_xmit lwt hook 2022-05-09 09:14:35 +02:00
lwtunnel.c lwtunnel: Validate RTA_ENCAP_TYPE attribute length 2022-01-11 15:35:14 +01:00
neighbour.c net: neigh: don't call kfree_skb() under spin_lock_irqsave() 2022-09-05 10:30:13 +02:00
net-procfs.c net-procfs: show net devices bound packet types 2022-02-01 17:27:08 +01:00
net-sysfs.c net: fix data-race in dev_isalive() 2022-06-29 09:03:22 +02:00
net-sysfs.h net-sysfs: add netdev_change_owner() 2020-02-26 20:07:25 -08:00
net-traces.c tcp: add tracepoint for checksum errors 2021-05-14 15:26:03 -07:00
net_namespace.c net: initialize init_net earlier 2022-04-13 20:59:03 +02:00
netclassid_cgroup.c bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode 2021-09-13 16:35:58 -07:00
netevent.c net: core: Correct function name netevent_unregister_notifier() in the kerneldoc 2021-03-28 17:56:56 -07:00
netpoll.c asm-generic/unaligned: Unify asm/unaligned.h around struct helper 2021-07-02 12:43:40 -07:00
netprio_cgroup.c bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode 2021-09-13 16:35:58 -07:00
of_net.c of: net: move of_net under net/ 2022-03-08 19:12:41 +01:00
page_pool.c page_pool: use relaxed atomic for release side accounting 2021-08-24 10:46:31 +01:00
pktgen.c pktgen: remove unused variable 2021-09-03 11:48:28 +01:00
ptp_classifier.c bpf: Refactor BPF_PROG_RUN into a function 2021-08-17 00:45:07 +02:00
request_sock.c tcp: add rcu protection around tp->fastopen_rsk 2019-10-13 10:13:08 -07:00
rtnetlink.c net: Write lock dev_base_lock without disabling bottom halves. 2022-06-29 09:03:22 +02:00
scm.c memcg: enable accounting for scm_fp_list objects 2021-07-20 06:00:38 -07:00
secure_seq.c tcp: Fix data-races around sysctl knobs related to SYN option. 2022-07-29 17:25:22 +02:00
selftests.c net: selftests: add MTU test 2021-07-22 00:52:04 -07:00
skbuff.c net/core/skbuff: Check the return value of skb_copy_bits() 2022-09-15 11:30:01 +02:00
skmsg.c skmsg: Schedule psock work if the cached skb exists on the psock 2022-10-26 12:34:46 +02:00
sock.c net: Fix a data-race around sysctl_net_busy_read. 2022-08-31 17:16:43 +02:00
sock_destructor.h skb_expand_head() adjust skb->truesize incorrectly 2021-10-22 12:35:51 -07:00
sock_diag.c bpf, net: Rework cookie generator as per-cpu one 2020-09-30 11:50:35 -07:00
sock_map.c bpf: Acquire map uref in .init_seq_private for sock{map,hash} iterator 2022-08-25 11:40:03 +02:00
sock_reuseport.c tcp: Fix data-races around sysctl_tcp_migrate_req. 2022-07-29 17:25:18 +02:00
stream.c net: If sock is dead don't access sock's sk_wq in sk_stream_wait_memory 2022-10-26 12:35:37 +02:00
sysctl_net_core.c net: Fix data-races around weight_p and dev_weight_[rt]x_bias. 2022-08-31 17:16:42 +02:00
timestamping.c net: Introduce a new MII time stamping interface. 2019-12-25 19:51:33 -08:00
tso.c net: tso: add UDP segmentation support 2020-06-18 20:46:23 -07:00
utils.c net: Fix skb->csum update in inet_proto_csum_replace16(). 2020-01-24 20:54:30 +01:00
xdp.c xdp: Move the rxq_info.mem clearing to unreg_mem_model() 2021-06-28 23:07:59 +02:00