Commit Graph

11215 Commits

Author SHA1 Message Date
Daniel Xu
60387731e6 netfilter: conntrack: Fix data-races around ct mark
[ Upstream commit 52d1aa8b82 ]

nf_conn:mark can be read from and written to in parallel. Use
READ_ONCE()/WRITE_ONCE() for reads and writes to prevent unwanted
compiler optimizations.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:04 +01:00
Christian Langrock
0c69a4658e xfrm: replay: Fix ESN wrap around for GSO
[ Upstream commit 4b549ccce9 ]

When using GSO it can happen that the wrong seq_hi is used for the last
packets before the wrap around. This can lead to double usage of a
sequence number. To avoid this, we should serialize this last GSO
packet.

Fixes: d7dbefc45c ("xfrm: Add xfrm_replay_overflow functions for offloading")
Co-developed-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Christian Langrock <christian.langrock@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:02 +01:00
Eyal Birger
ecc6ce4fdf xfrm: fix "disable_policy" on ipv4 early demux
[ Upstream commit 3a5913183a ]

The commit in the "Fixes" tag tried to avoid a case where policy check
is ignored due to dst caching in next hops.

However, when the traffic is locally consumed, the dst may be cached
in a local TCP or UDP socket as part of early demux. In this case the
"disable_policy" flag is not checked as ip_route_input_noref() was only
called before caching, and thus, packets after the initial packet in a
flow will be dropped if not matching policies.

Fix by checking the "disable_policy" flag also when a valid dst is
already available.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216557
Reported-by: Monil Patel <monil191989@gmail.com>
Fixes: e6175a2ed1 ("xfrm: fix "disable_policy" flag use when arriving from different devices")
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>

----

v2: use dev instead of skb->dev
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:02 +01:00
Eric Dumazet
b49026d9c8 tcp: cdg: allow tcp_cdg_release() to be called multiple times
commit 72e560cb8c upstream.

Apparently, mptcp is able to call tcp_disconnect() on an already
disconnected flow. This is generally fine, unless current congestion
control is CDG, because it might trigger a double-free [1]

Instead of fixing MPTCP, and future bugs, we can make tcp_disconnect()
more resilient.

[1]
BUG: KASAN: double-free in slab_free mm/slub.c:3539 [inline]
BUG: KASAN: double-free in kfree+0xe2/0x580 mm/slub.c:4567

CPU: 0 PID: 3645 Comm: kworker/0:7 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Workqueue: events mptcp_worker
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:317 [inline]
print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
kasan_report_invalid_free+0x81/0x190 mm/kasan/report.c:462
____kasan_slab_free+0x18b/0x1c0 mm/kasan/common.c:356
kasan_slab_free include/linux/kasan.h:200 [inline]
slab_free_hook mm/slub.c:1759 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785
slab_free mm/slub.c:3539 [inline]
kfree+0xe2/0x580 mm/slub.c:4567
tcp_disconnect+0x980/0x1e20 net/ipv4/tcp.c:3145
__mptcp_close_ssk+0x5ca/0x7e0 net/mptcp/protocol.c:2327
mptcp_do_fastclose net/mptcp/protocol.c:2592 [inline]
mptcp_worker+0x78c/0xff0 net/mptcp/protocol.c:2627
process_one_work+0x991/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>

Allocated by task 3671:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:437 [inline]
____kasan_kmalloc mm/kasan/common.c:516 [inline]
____kasan_kmalloc mm/kasan/common.c:475 [inline]
__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525
kmalloc_array include/linux/slab.h:640 [inline]
kcalloc include/linux/slab.h:671 [inline]
tcp_cdg_init+0x10d/0x170 net/ipv4/tcp_cdg.c:380
tcp_init_congestion_control+0xab/0x550 net/ipv4/tcp_cong.c:193
tcp_reinit_congestion_control net/ipv4/tcp_cong.c:217 [inline]
tcp_set_congestion_control+0x96c/0xaa0 net/ipv4/tcp_cong.c:391
do_tcp_setsockopt+0x505/0x2320 net/ipv4/tcp.c:3513
tcp_setsockopt+0xd4/0x100 net/ipv4/tcp.c:3801
mptcp_setsockopt+0x35f/0x2570 net/mptcp/sockopt.c:844
__sys_setsockopt+0x2d6/0x690 net/socket.c:2252
__do_sys_setsockopt net/socket.c:2263 [inline]
__se_sys_setsockopt net/socket.c:2260 [inline]
__x64_sys_setsockopt+0xba/0x150 net/socket.c:2260
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 16:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:45
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:367 [inline]
____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329
kasan_slab_free include/linux/kasan.h:200 [inline]
slab_free_hook mm/slub.c:1759 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785
slab_free mm/slub.c:3539 [inline]
kfree+0xe2/0x580 mm/slub.c:4567
tcp_cleanup_congestion_control+0x70/0x120 net/ipv4/tcp_cong.c:226
tcp_v4_destroy_sock+0xdd/0x750 net/ipv4/tcp_ipv4.c:2254
tcp_v6_destroy_sock+0x11/0x20 net/ipv6/tcp_ipv6.c:1969
inet_csk_destroy_sock+0x196/0x440 net/ipv4/inet_connection_sock.c:1157
tcp_done+0x23b/0x340 net/ipv4/tcp.c:4649
tcp_rcv_state_process+0x40e7/0x4990 net/ipv4/tcp_input.c:6624
tcp_v6_do_rcv+0x3fc/0x13c0 net/ipv6/tcp_ipv6.c:1525
tcp_v6_rcv+0x2e8e/0x3830 net/ipv6/tcp_ipv6.c:1759
ip6_protocol_deliver_rcu+0x2db/0x1950 net/ipv6/ip6_input.c:439
ip6_input_finish+0x14c/0x2c0 net/ipv6/ip6_input.c:484
NF_HOOK include/linux/netfilter.h:302 [inline]
NF_HOOK include/linux/netfilter.h:296 [inline]
ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:493
dst_input include/net/dst.h:455 [inline]
ip6_rcv_finish+0x193/0x2c0 net/ipv6/ip6_input.c:79
ip_sabotage_in net/bridge/br_netfilter_hooks.c:874 [inline]
ip_sabotage_in+0x1fa/0x260 net/bridge/br_netfilter_hooks.c:865
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xc5/0x1f0 net/netfilter/core.c:614
nf_hook.constprop.0+0x3ac/0x650 include/linux/netfilter.h:257
NF_HOOK include/linux/netfilter.h:300 [inline]
ipv6_rcv+0x9e/0x380 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5485
__netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5599
netif_receive_skb_internal net/core/dev.c:5685 [inline]
netif_receive_skb+0x12f/0x8d0 net/core/dev.c:5744
NF_HOOK include/linux/netfilter.h:302 [inline]
NF_HOOK include/linux/netfilter.h:296 [inline]
br_pass_frame_up+0x303/0x410 net/bridge/br_input.c:68
br_handle_frame_finish+0x909/0x1aa0 net/bridge/br_input.c:199
br_nf_hook_thresh+0x2f8/0x3d0 net/bridge/br_netfilter_hooks.c:1041
br_nf_pre_routing_finish_ipv6+0x695/0xef0 net/bridge/br_netfilter_ipv6.c:207
NF_HOOK include/linux/netfilter.h:302 [inline]
br_nf_pre_routing_ipv6+0x417/0x7c0 net/bridge/br_netfilter_ipv6.c:237
br_nf_pre_routing+0x1496/0x1fe0 net/bridge/br_netfilter_hooks.c:507
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:255 [inline]
br_handle_frame+0x9c9/0x12d0 net/bridge/br_input.c:399
__netif_receive_skb_core+0x9fe/0x38f0 net/core/dev.c:5379
__netif_receive_skb_one_core+0xae/0x180 net/core/dev.c:5483
__netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5599
process_backlog+0x3a0/0x7c0 net/core/dev.c:5927
__napi_poll+0xb3/0x6d0 net/core/dev.c:6494
napi_poll net/core/dev.c:6561 [inline]
net_rx_action+0x9c1/0xd90 net/core/dev.c:6672
__do_softirq+0x1d0/0x9c8 kernel/softirq.c:571

Fixes: 2b0a8c9eee ("tcp: add CDG congestion control")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:50 +01:00
Lu Wei
13ecaa6832 tcp: prohibit TCP_REPAIR_OPTIONS if data was already sent
[ Upstream commit 0c175da7b0 ]

If setsockopt with option name of TCP_REPAIR_OPTIONS and opt_code
of TCPOPT_SACK_PERM is called to enable sack after data is sent
and dupacks are received , it will trigger a warning in function
tcp_verify_left_out() as follows:

============================================
WARNING: CPU: 8 PID: 0 at net/ipv4/tcp_input.c:2132
tcp_timeout_mark_lost+0x154/0x160
tcp_enter_loss+0x2b/0x290
tcp_retransmit_timer+0x50b/0x640
tcp_write_timer_handler+0x1c8/0x340
tcp_write_timer+0xe5/0x140
call_timer_fn+0x3a/0x1b0
__run_timers.part.0+0x1bf/0x2d0
run_timer_softirq+0x43/0xb0
__do_softirq+0xfd/0x373
__irq_exit_rcu+0xf6/0x140

The warning is caused in the following steps:
1. a socket named socketA is created
2. socketA enters repair mode without build a connection
3. socketA calls connect() and its state is changed to TCP_ESTABLISHED
   directly
4. socketA leaves repair mode
5. socketA calls sendmsg() to send data, packets_out and sack_outs(dup
   ack receives) increase
6. socketA enters repair mode again
7. socketA calls setsockopt with TCPOPT_SACK_PERM to enable sack
8. retransmit timer expires, it calls tcp_timeout_mark_lost(), lost_out
   increases
9. sack_outs + lost_out > packets_out triggers since lost_out and
   sack_outs increase repeatly

In function tcp_timeout_mark_lost(), tp->sacked_out will be cleared if
Step7 not happen and the warning will not be triggered. As suggested by
Denis and Eric, TCP_REPAIR_OPTIONS should be prohibited if data was
already sent.

socket-tcp tests in CRIU has been tested as follows:
$ sudo ./test/zdtm.py run -t zdtm/static/socket-tcp*  --keep-going \
       --ignore-taint

socket-tcp* represent all socket-tcp tests in test/zdtm/static/.

Fixes: b139ba4e90 ("tcp: Repair connection-time negotiated parameters")
Signed-off-by: Lu Wei <luwei32@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:18 +01:00
Wang Yufen
e991558189 bpf, sockmap: Fix sk->sk_forward_alloc warn_on in sk_stream_kill_queues
[ Upstream commit d8616ee2af ]

During TCP sockmap redirect pressure test, the following warning is triggered:

WARNING: CPU: 3 PID: 2145 at net/core/stream.c:205 sk_stream_kill_queues+0xbc/0xd0
CPU: 3 PID: 2145 Comm: iperf Kdump: loaded Tainted: G        W         5.10.0+ #9
Call Trace:
 inet_csk_destroy_sock+0x55/0x110
 inet_csk_listen_stop+0xbb/0x380
 tcp_close+0x41b/0x480
 inet_release+0x42/0x80
 __sock_release+0x3d/0xa0
 sock_close+0x11/0x20
 __fput+0x9d/0x240
 task_work_run+0x62/0x90
 exit_to_user_mode_prepare+0x110/0x120
 syscall_exit_to_user_mode+0x27/0x190
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The reason we observed is that:

When the listener is closing, a connection may have completed the three-way
handshake but not accepted, and the client has sent some packets. The child
sks in accept queue release by inet_child_forget()->inet_csk_destroy_sock(),
but psocks of child sks have not released.

To fix, add sock_map_destroy to release psocks.

Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220524075311.649153-1-wangyufen@huawei.com
Stable-dep-of: 8bbabb3fdd ("bpf, sock_map: Move cancel_work_sync() out of sock lock")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:15 +01:00
Wang Yufen
95adbd2ac8 bpf, sockmap: Fix the sk->sk_forward_alloc warning of sk_stream_kill_queues
[ Upstream commit 8ec95b9471 ]

When running `test_sockmap` selftests, the following warning appears:

  WARNING: CPU: 2 PID: 197 at net/core/stream.c:205 sk_stream_kill_queues+0xd3/0xf0
  Call Trace:
  <TASK>
  inet_csk_destroy_sock+0x55/0x110
  tcp_rcv_state_process+0xd28/0x1380
  ? tcp_v4_do_rcv+0x77/0x2c0
  tcp_v4_do_rcv+0x77/0x2c0
  __release_sock+0x106/0x130
  __tcp_close+0x1a7/0x4e0
  tcp_close+0x20/0x70
  inet_release+0x3c/0x80
  __sock_release+0x3a/0xb0
  sock_close+0x14/0x20
  __fput+0xa3/0x260
  task_work_run+0x59/0xb0
  exit_to_user_mode_prepare+0x1b3/0x1c0
  syscall_exit_to_user_mode+0x19/0x50
  do_syscall_64+0x48/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae

The root case is in commit 84472b436e ("bpf, sockmap: Fix more uncharged
while msg has more_data"), where I used msg->sg.size to replace the tosend,
causing breakage:

  if (msg->apply_bytes && msg->apply_bytes < tosend)
    tosend = psock->apply_bytes;

Fixes: 84472b436e ("bpf, sockmap: Fix more uncharged while msg has more_data")
Reported-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/1667266296-8794-1-git-send-email-wangyufen@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:14 +01:00
Kuniyuki Iwashima
828577e0ba tcp/udp: Make early_demux back namespacified.
commit 11052589cf upstream.

Commit e21145a987 ("ipv4: namespacify ip_early_demux sysctl knob") made
it possible to enable/disable early_demux on a per-netns basis.  Then, we
introduced two knobs, tcp_early_demux and udp_early_demux, to switch it for
TCP/UDP in commit dddb64bcb3 ("net: Add sysctl to toggle early demux for
tcp and udp").  However, the .proc_handler() was wrong and actually
disabled us from changing the behaviour in each netns.

We can execute early_demux if net.ipv4.ip_early_demux is on and each proto
.early_demux() handler is not NULL.  When we toggle (tcp|udp)_early_demux,
the change itself is saved in each netns variable, but the .early_demux()
handler is a global variable, so the handler is switched based on the
init_net's sysctl variable.  Thus, netns (tcp|udp)_early_demux knobs have
nothing to do with the logic.  Whether we CAN execute proto .early_demux()
is always decided by init_net's sysctl knob, and whether we DO it or not is
by each netns ip_early_demux knob.

This patch namespacifies (tcp|udp)_early_demux again.  For now, the users
of the .early_demux() handler are TCP and UDP only, and they are called
directly to avoid retpoline.  So, we can remove the .early_demux() handler
from inet6?_protos and need not dereference them in ip6?_rcv_finish_core().
If another proto needs .early_demux(), we can restore it at that time.

Fixes: dddb64bcb3 ("net: Add sysctl to toggle early demux for tcp and udp")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20220713175207.7727-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:15:38 +01:00
Nicolas Dichtel
b317d53680 nh: fix scope used to find saddr when adding non gw nh
[ Upstream commit bac0f937c3 ]

As explained by Julian, fib_nh_scope is related to fib_nh_gw4, but
fib_info_update_nhc_saddr() needs the scope of the route, which is
the scope "before" fib_nh_scope, ie fib_nh_scope - 1.

This patch fixes the problem described in commit 747c143072 ("ip: fix
dflt addr selection for connected nexthop").

Fixes: 597cfe4fc3 ("nexthop: Add support for IPv4 nexthops")
Link: https://lore.kernel.org/netdev/6c8a44ba-c2d5-cdf-c5c7-5baf97cba38@ssi.bg/
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:59:19 +09:00
Neal Cardwell
9b171fdcbf tcp: fix indefinite deferral of RTO with SACK reneging
[ Upstream commit 3d2af9cce3 ]

This commit fixes a bug that can cause a TCP data sender to repeatedly
defer RTOs when encountering SACK reneging.

The bug is that when we're in fast recovery in a scenario with SACK
reneging, every time we get an ACK we call tcp_check_sack_reneging()
and it can note the apparent SACK reneging and rearm the RTO timer for
srtt/2 into the future. In some SACK reneging scenarios that can
happen repeatedly until the receive window fills up, at which point
the sender can't send any more, the ACKs stop arriving, and the RTO
fires at srtt/2 after the last ACK. But that can take far too long
(O(10 secs)), since the connection is stuck in fast recovery with a
low cwnd that cannot grow beyond ssthresh, even if more bandwidth is
available.

This fix changes the logic in tcp_check_sack_reneging() to only rearm
the RTO timer if data is cumulatively ACKed, indicating forward
progress. This avoids this kind of nearly infinite loop of RTO timer
re-arming. In addition, this meets the goals of
tcp_check_sack_reneging() in handling Windows TCP behavior that looks
temporarily like SACK reneging but is not really.

Many thanks to Jakub Kicinski and Neil Spring, who reported this issue
and provided critical packet traces that enabled root-causing this
issue. Also, many thanks to Jakub Kicinski for testing this fix.

Fixes: 5ae344c949 ("tcp: reduce spurious retransmits due to transient SACK reneging")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: Neil Spring <ntspring@fb.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Tested-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20221021170821.1093930-1-ncardwell.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:59:17 +09:00
Lu Wei
a85d39f14a tcp: fix a signed-integer-overflow bug in tcp_add_backlog()
[ Upstream commit ec791d8149 ]

The type of sk_rcvbuf and sk_sndbuf in struct sock is int, and
in tcp_add_backlog(), the variable limit is caculated by adding
sk_rcvbuf, sk_sndbuf and 64 * 1024, it may exceed the max value
of int and overflow. This patch reduces the limit budget by
halving the sndbuf to solve this issue since ACK packets are much
smaller than the payload.

Fixes: c9c3321257 ("tcp: add tcp_add_backlog()")
Signed-off-by: Lu Wei <luwei32@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:59:17 +09:00
Eric Dumazet
2437f3c5c6 tcp: minor optimization in tcp_add_backlog()
[ Upstream commit d519f35096 ]

If packet is going to be coalesced, sk_sndbuf/sk_rcvbuf values
are not used. Defer their access to the point we need them.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: ec791d8149 ("tcp: fix a signed-integer-overflow bug in tcp_add_backlog()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:59:16 +09:00
Kuniyuki Iwashima
a8df9d0428 udp: Update reuse->has_conns under reuseport_lock.
[ Upstream commit 69421bf984 ]

When we call connect() for a UDP socket in a reuseport group, we have
to update sk->sk_reuseport_cb->has_conns to 1.  Otherwise, the kernel
could select a unconnected socket wrongly for packets sent to the
connected socket.

However, the current way to set has_conns is illegal and possible to
trigger that problem.  reuseport_has_conns() changes has_conns under
rcu_read_lock(), which upgrades the RCU reader to the updater.  Then,
it must do the update under the updater's lock, reuseport_lock, but
it doesn't for now.

For this reason, there is a race below where we fail to set has_conns
resulting in the wrong socket selection.  To avoid the race, let's split
the reader and updater with proper locking.

 cpu1                               cpu2
+----+                             +----+

__ip[46]_datagram_connect()        reuseport_grow()
.                                  .
|- reuseport_has_conns(sk, true)   |- more_reuse = __reuseport_alloc(more_socks_size)
|  .                               |
|  |- rcu_read_lock()
|  |- reuse = rcu_dereference(sk->sk_reuseport_cb)
|  |
|  |                               |  /* reuse->has_conns == 0 here */
|  |                               |- more_reuse->has_conns = reuse->has_conns
|  |- reuse->has_conns = 1         |  /* more_reuse->has_conns SHOULD BE 1 HERE */
|  |                               |
|  |                               |- rcu_assign_pointer(reuse->socks[i]->sk_reuseport_cb,
|  |                               |                     more_reuse)
|  `- rcu_read_unlock()            `- kfree_rcu(reuse, rcu)
|
|- sk->sk_state = TCP_ESTABLISHED

Note the likely(reuse) in reuseport_has_conns_set() is always true,
but we put the test there for ease of review.  [0]

For the record, usually, sk_reuseport_cb is changed under lock_sock().
The only exception is reuseport_grow() & TCP reqsk migration case.

  1) shutdown() TCP listener, which is moved into the latter part of
     reuse->socks[] to migrate reqsk.

  2) New listen() overflows reuse->socks[] and call reuseport_grow().

  3) reuse->max_socks overflows u16 with the new listener.

  4) reuseport_grow() pops the old shutdown()ed listener from the array
     and update its sk->sk_reuseport_cb as NULL without lock_sock().

shutdown()ed TCP sk->sk_reuseport_cb can be changed without lock_sock(),
but, reuseport_has_conns_set() is called only for UDP under lock_sock(),
so likely(reuse) never be false in reuseport_has_conns_set().

[0]: https://lore.kernel.org/netdev/CANn89iLja=eQHbsM_Ta2sQF0tOGU8vAGrh_izRuuHjuO1ouUag@mail.gmail.com/

Fixes: acdcecc612 ("udp: correct reuseport selection with connected sockets")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20221014182625.89913-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-29 10:12:56 +02:00
Eric Dumazet
1663629bc3 tcp: annotate data-race around tcp_md5sig_pool_populated
[ Upstream commit aacd467c0a ]

tcp_md5sig_pool_populated can be read while another thread
changes its value.

The race has no consequence because allocations
are protected with tcp_md5sig_mutex.

This patch adds READ_ONCE() and WRITE_ONCE() to document
the race and silence KCSAN.

Reported-by: Abhishek Shah <abhishek.shah@columbia.edu>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:35:33 +02:00
Eric Dumazet
7aef5082c5 once: add DO_ONCE_SLOW() for sleepable contexts
[ Upstream commit 62c07983be ]

Christophe Leroy reported a ~80ms latency spike
happening at first TCP connect() time.

This is because __inet_hash_connect() uses get_random_once()
to populate a perturbation table which became quite big
after commit 4c2c8f03a5 ("tcp: increase source port perturb table to 2^16")

get_random_once() uses DO_ONCE(), which block hard irqs for the duration
of the operation.

This patch adds DO_ONCE_SLOW() which uses a mutex instead of a spinlock
for operations where we prefer to stay in process context.

Then __inet_hash_connect() can use get_random_slow_once()
to populate its perturbation table.

Fixes: 4c2c8f03a5 ("tcp: increase source port perturb table to 2^16")
Fixes: 190cc82489 ("tcp: change source port randomizarion at connect() time")
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/netdev/CANn89iLAEYBaoYajy0Y9UmGFff5GPxDUoG-ErVB2jDdRNQ5Tug@mail.gmail.com/T/#t
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:34:49 +02:00
Neal Cardwell
49d429760d tcp: fix tcp_cwnd_validate() to not forget is_cwnd_limited
[ Upstream commit f4ce91ce12 ]

This commit fixes a bug in the tracking of max_packets_out and
is_cwnd_limited. This bug can cause the connection to fail to remember
that is_cwnd_limited is true, causing the connection to fail to grow
cwnd when it should, causing throughput to be lower than it should be.

The following event sequence is an example that triggers the bug:

 (a) The connection is cwnd_limited, but packets_out is not at its
     peak due to TSO deferral deciding not to send another skb yet.
     In such cases the connection can advance max_packets_seq and set
     tp->is_cwnd_limited to true and max_packets_out to a small
     number.

(b) Then later in the round trip the connection is pacing-limited (not
     cwnd-limited), and packets_out is larger. In such cases the
     connection would raise max_packets_out to a bigger number but
     (unexpectedly) flip tp->is_cwnd_limited from true to false.

This commit fixes that bug.

One straightforward fix would be to separately track (a) the next
window after max_packets_out reaches a maximum, and (b) the next
window after tp->is_cwnd_limited is set to true. But this would
require consuming an extra u32 sequence number.

Instead, to save space we track only the most important
information. Specifically, we track the strongest available signal of
the degree to which the cwnd is fully utilized:

(1) If the connection is cwnd-limited then we remember that fact for
the current window.

(2) If the connection not cwnd-limited then we track the maximum
number of outstanding packets in the current window.

In particular, note that the new logic cannot trigger the buggy
(a)/(b) sequence above because with the new logic a condition where
tp->packets_out > tp->max_packets_out can only trigger an update of
tp->is_cwnd_limited if tp->is_cwnd_limited is false.

This first showed up in a testing of a BBRv2 dev branch, but this
buggy behavior highlighted a general issue with the
tcp_cwnd_validate() logic that can cause cwnd to fail to increase at
the proper rate for any TCP congestion control, including Reno or
CUBIC.

Fixes: ca8a226343 ("tcp: make cwnd-limited checks measurement-based, and gentler")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Kevin(Yudong) Yang <yyd@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:34:48 +02:00
Phil Sutter
1454a26cb1 netfilter: nft_fib: Fix for rpath check with VRF devices
[ Upstream commit 2a8a7c0eaa ]

Analogous to commit b575b24b8e ("netfilter: Fix rpfilter
dropping vrf packets by mistake") but for nftables fib expression:
Add special treatment of VRF devices so that typical reverse path
filtering via 'fib saddr . iif oif' expression works as expected.

Fixes: f6d0cbcf09 ("netfilter: nf_tables: add fib expression")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:34:47 +02:00
sewookseo
d9bf46e747 net: Find dst with sk's xfrm policy not ctl_sk
commit e22aa14866 upstream.

If we set XFRM security policy by calling setsockopt with option
IPV6_XFRM_POLICY, the policy will be stored in 'sock_policy' in 'sock'
struct. However tcp_v6_send_response doesn't look up dst_entry with the
actual socket but looks up with tcp control socket. This may cause a
problem that a RST packet is sent without ESP encryption & peer's TCP
socket can't receive it.
This patch will make the function look up dest_entry with actual socket,
if the socket has XFRM policy(sock_policy), so that the TCP response
packet via this function can be encrypted, & aligned on the encrypted
TCP socket.

Tested: We encountered this problem when a TCP socket which is encrypted
in ESP transport mode encryption, receives challenge ACK at SYN_SENT
state. After receiving challenge ACK, TCP needs to send RST to
establish the socket at next SYN try. But the RST was not encrypted &
peer TCP socket still remains on ESTABLISHED state.
So we verified this with test step as below.
[Test step]
1. Making a TCP state mismatch between client(IDLE) & server(ESTABLISHED).
2. Client tries a new connection on the same TCP ports(src & dst).
3. Server will return challenge ACK instead of SYN,ACK.
4. Client will send RST to server to clear the SOCKET.
5. Client will retransmit SYN to server on the same TCP ports.
[Expected result]
The TCP connection should be established.

Cc: Maciej Żenczykowski <maze@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Sehee Lee <seheele@google.com>
Signed-off-by: Sewook Seo <sewookseo@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-23 14:15:51 +02:00
Neal Cardwell
a96b1d33ec tcp: fix early ETIMEDOUT after spurious non-SACK RTO
[ Upstream commit 686dc2db2a ]

Fix a bug reported and analyzed by Nagaraj Arankal, where the handling
of a spurious non-SACK RTO could cause a connection to fail to clear
retrans_stamp, causing a later RTO to very prematurely time out the
connection with ETIMEDOUT.

Here is the buggy scenario, expanding upon Nagaraj Arankal's excellent
report:

(*1) Send one data packet on a non-SACK connection

(*2) Because no ACK packet is received, the packet is retransmitted
     and we enter CA_Loss; but this retransmission is spurious.

(*3) The ACK for the original data is received. The transmitted packet
     is acknowledged.  The TCP timestamp is before the retrans_stamp,
     so tcp_may_undo() returns true, and tcp_try_undo_loss() returns
     true without changing state to Open (because tcp_is_sack() is
     false), and tcp_process_loss() returns without calling
     tcp_try_undo_recovery().  Normally after undoing a CA_Loss
     episode, tcp_fastretrans_alert() would see that the connection
     has returned to CA_Open and fall through and call
     tcp_try_to_open(), which would set retrans_stamp to 0.  However,
     for non-SACK connections we hold the connection in CA_Loss, so do
     not fall through to call tcp_try_to_open() and do not set
     retrans_stamp to 0. So retrans_stamp is (erroneously) still
     non-zero.

     At this point the first "retransmission event" has passed and
     been recovered from. Any future retransmission is a completely
     new "event". However, retrans_stamp is erroneously still
     set. (And we are still in CA_Loss, which is correct.)

(*4) After 16 minutes (to correspond with tcp_retries2=15), a new data
     packet is sent. Note: No data is transmitted between (*3) and
     (*4) and we disabled keep alives.

     The socket's timeout SHOULD be calculated from this point in
     time, but instead it's calculated from the prior "event" 16
     minutes ago (step (*2)).

(*5) Because no ACK packet is received, the packet is retransmitted.

(*6) At the time of the 2nd retransmission, the socket returns
     ETIMEDOUT, prematurely, because retrans_stamp is (erroneously)
     too far in the past (set at the time of (*2)).

This commit fixes this bug by ensuring that we reuse in
tcp_try_undo_loss() the same careful logic for non-SACK connections
that we have in tcp_try_undo_recovery(). To avoid duplicating logic,
we factor out that logic into a new
tcp_is_non_sack_preventing_reopen() helper and call that helper from
both undo functions.

Fixes: da34ac7626 ("tcp: only undo on partial ACKs in CA_Loss")
Reported-by: Nagaraj Arankal <nagaraj.p.arankal@hpe.com>
Link: https://lore.kernel.org/all/SJ0PR84MB1847BE6C24D274C46A1B9B0EB27A9@SJ0PR84MB1847.NAMPRD84.PROD.OUTLOOK.COM/
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220903121023.866900-1-ncardwell.kernel@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:30:06 +02:00
Eric Dumazet
8527c9a6bf tcp: TX zerocopy should not sense pfmemalloc status
[ Upstream commit 3261400639 ]

We got a recent syzbot report [1] showing a possible misuse
of pfmemalloc page status in TCP zerocopy paths.

Indeed, for pages coming from user space or other layers,
using page_is_pfmemalloc() is moot, and possibly could give
false positives.

There has been attempts to make page_is_pfmemalloc() more robust,
but not using it in the first place in this context is probably better,
removing cpu cycles.

Note to stable teams :

You need to backport 84ce071e38 ("net: introduce
__skb_fill_page_desc_noacc") as a prereq.

Race is more probable after commit c07aea3ef4
("mm: add a signature in struct page") because page_is_pfmemalloc()
is now using low order bit from page->lru.next, which can change
more often than page->index.

Low order bit should never be set for lru.next (when used as an anchor
in LRU list), so KCSAN report is mostly a false positive.

Backporting to older kernel versions seems not necessary.

[1]
BUG: KCSAN: data-race in lru_add_fn / tcp_build_frag

write to 0xffffea0004a1d2c8 of 8 bytes by task 18600 on cpu 0:
__list_add include/linux/list.h:73 [inline]
list_add include/linux/list.h:88 [inline]
lruvec_add_folio include/linux/mm_inline.h:105 [inline]
lru_add_fn+0x440/0x520 mm/swap.c:228
folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246
folio_batch_add_and_move mm/swap.c:263 [inline]
folio_add_lru+0xf1/0x140 mm/swap.c:490
filemap_add_folio+0xf8/0x150 mm/filemap.c:948
__filemap_get_folio+0x510/0x6d0 mm/filemap.c:1981
pagecache_get_page+0x26/0x190 mm/folio-compat.c:104
grab_cache_page_write_begin+0x2a/0x30 mm/folio-compat.c:116
ext4_da_write_begin+0x2dd/0x5f0 fs/ext4/inode.c:2988
generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738
ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:270
ext4_file_write_iter+0x2e3/0x1210
call_write_iter include/linux/fs.h:2187 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x468/0x760 fs/read_write.c:578
ksys_write+0xe8/0x1a0 fs/read_write.c:631
__do_sys_write fs/read_write.c:643 [inline]
__se_sys_write fs/read_write.c:640 [inline]
__x64_sys_write+0x3e/0x50 fs/read_write.c:640
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffea0004a1d2c8 of 8 bytes by task 18611 on cpu 1:
page_is_pfmemalloc include/linux/mm.h:1740 [inline]
__skb_fill_page_desc include/linux/skbuff.h:2422 [inline]
skb_fill_page_desc include/linux/skbuff.h:2443 [inline]
tcp_build_frag+0x613/0xb20 net/ipv4/tcp.c:1018
do_tcp_sendpages+0x3e8/0xaf0 net/ipv4/tcp.c:1075
tcp_sendpage_locked net/ipv4/tcp.c:1140 [inline]
tcp_sendpage+0x89/0xb0 net/ipv4/tcp.c:1150
inet_sendpage+0x7f/0xc0 net/ipv4/af_inet.c:833
kernel_sendpage+0x184/0x300 net/socket.c:3561
sock_sendpage+0x5a/0x70 net/socket.c:1054
pipe_to_sendpage+0x128/0x160 fs/splice.c:361
splice_from_pipe_feed fs/splice.c:415 [inline]
__splice_from_pipe+0x222/0x4d0 fs/splice.c:559
splice_from_pipe fs/splice.c:594 [inline]
generic_splice_sendpage+0x89/0xc0 fs/splice.c:743
do_splice_from fs/splice.c:764 [inline]
direct_splice_actor+0x80/0xa0 fs/splice.c:931
splice_direct_to_actor+0x305/0x620 fs/splice.c:886
do_splice_direct+0xfb/0x180 fs/splice.c:974
do_sendfile+0x3bf/0x910 fs/read_write.c:1249
__do_sys_sendfile64 fs/read_write.c:1317 [inline]
__se_sys_sendfile64 fs/read_write.c:1303 [inline]
__x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000000 -> 0xffffea0004a1d288

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18611 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022

Fixes: c07aea3ef4 ("mm: add a signature in struct page")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:30:05 +02:00
David Howells
24a4e79d92 rxrpc: Fix ICMP/ICMP6 error handling
[ Upstream commit ac56a0b48d ]

Because rxrpc pretends to be a tunnel on top of a UDP/UDP6 socket, allowing
it to siphon off UDP packets early in the handling of received UDP packets
thereby avoiding the packet going through the UDP receive queue, it doesn't
get ICMP packets through the UDP ->sk_error_report() callback.  In fact, it
doesn't appear that there's any usable option for getting hold of ICMP
packets.

Fix this by adding a new UDP encap hook to distribute error messages for
UDP tunnels.  If the hook is set, then the tunnel driver will be able to
see ICMP packets.  The hook provides the offset into the packet of the UDP
header of the original packet that caused the notification.

An alternative would be to call the ->error_handler() hook - but that
requires that the skbuff be cloned (as ip_icmp_error() or ipv6_cmp_error()
do, though isn't really necessary or desirable in rxrpc's case is we want
to parse them there and then, not queue them).

Changes
=======
ver #3)
 - Fixed an uninitialised variable.

ver #2)
 - Fixed some missing CONFIG_AF_RXRPC_IPV6 conditionals.

Fixes: 5271953cad ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:30:05 +02:00
Nicolas Dichtel
57f1407ca1 ip: fix triggering of 'icmp redirect'
commit eb55dc09b5 upstream.

__mkroute_input() uses fib_validate_source() to trigger an icmp redirect.
My understanding is that fib_validate_source() is used to know if the src
address and the gateway address are on the same link. For that,
fib_validate_source() returns 1 (same link) or 0 (not the same network).
__mkroute_input() is the only user of these positive values, all other
callers only look if the returned value is negative.

Since the below patch, fib_validate_source() didn't return anymore 1 when
both addresses are on the same network, because the route lookup returns
RT_SCOPE_LINK instead of RT_SCOPE_HOST. But this is, in fact, right.
Let's adapat the test to return 1 again when both addresses are on the same
link.

CC: stable@vger.kernel.org
Fixes: 747c143072 ("ip: fix dflt addr selection for connected nexthop")
Reported-by: kernel test robot <yujie.liu@intel.com>
Reported-by: Heng Qi <hengqi@linux.alibaba.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220829100121.3821-1-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08 12:28:07 +02:00
Eric Dumazet
aca9d0acda tcp: annotate data-race around challenge_timestamp
[ Upstream commit 8c70521238 ]

challenge_timestamp can be read an written by concurrent threads.

This was expected, but we need to annotate the race to avoid potential issues.

Following patch moves challenge_timestamp and challenge_count
to per-netns storage to provide better isolation.

Fixes: 354e4aa391 ("tcp: RFC 5961 5.2 Blind Data Injection Attack Mitigation")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-08 12:28:03 +02:00
Kuniyuki Iwashima
b340f83daf net: Fix data-races around sysctl_devconf_inherit_init_net.
[ Upstream commit a5612ca10d ]

While reading sysctl_devconf_inherit_init_net, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 856c395cfa ("net: introduce a knob to control whether to inherit devconf config")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31 17:16:44 +02:00
Kuniyuki Iwashima
70564ad8d1 net: Fix data-races around sysctl_max_skb_frags.
[ Upstream commit 657b991afb ]

While reading sysctl_max_skb_frags, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 5f74f82ea3 ("net:Add sysctl_max_skb_frags")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31 17:16:44 +02:00
Paolo Abeni
a07f3af639 tcp: expose the tcp_mark_push() and tcp_skb_entail() helpers
[ Upstream commit 04d8825c30 ]

the tcp_skb_entail() helper is actually skb_entail(), renamed
to provide proper scope.

    The two helper will be used by the next patch.

RFC -> v1:
 - rename skb_entail to tcp_skb_entail (Eric)

Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31 17:16:44 +02:00
Kuniyuki Iwashima
d39a02760b net: Fix data-races around sysctl_optmem_max.
[ Upstream commit 7de6d09f51 ]

While reading sysctl_optmem_max, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31 17:16:43 +02:00
Kuniyuki Iwashima
33372f2b6c net: Fix data-races around sysctl_[rw]mem_(max|default).
[ Upstream commit 1227c1771d ]

While reading sysctl_[rw]mem_(max|default), they can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31 17:16:42 +02:00
Eric Dumazet
aa480f7d74 tcp: fix over estimation in sk_forced_mem_schedule()
commit c4ee118561 upstream.

sk_forced_mem_schedule() has a bug similar to ones fixed
in commit 7c80b038d2 ("net: fix sk_wmem_schedule() and
sk_rmem_schedule() errors")

While this bug has little chance to trigger in old kernels,
we need to fix it before the following patch.

Fixes: d83769a580 ("tcp: fix possible deadlock in tcp_send_fin()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-17 14:24:29 +02:00
Eric Dumazet
8fd69d3df9 ipv6: add READ_ONCE(sk->sk_bound_dev_if) in INET6_MATCH()
[ Upstream commit 5d368f0328 ]

INET6_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET6_MATCH() an inline function
to ease our changes.

v2: inline function only defined if IS_ENABLED(CONFIG_IPV6)
    Change the name to inet6_match(), this is no longer a macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:23:36 +02:00
Eric Dumazet
68bf74ec95 inet: add READ_ONCE(sk->sk_bound_dev_if) in INET_MATCH()
[ Upstream commit 4915d50e30 ]

INET_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET_MATCH() an inline function
to ease our changes.

v2:

We remove the 32bit version of it, as modern compilers
should generate the same code really, no need to
try to be smarter.

Also make 'struct net *net' the first argument.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:23:35 +02:00
Yonglong Li
273c11d9a9 tcp: make retransmitted SKB fit into the send window
[ Upstream commit 536a6c8e05 ]

current code of __tcp_retransmit_skb only check TCP_SKB_CB(skb)->seq
in send window, and TCP_SKB_CB(skb)->seq_end maybe out of send window.
If receiver has shrunk his window, and skb is out of new window,  it
should retransmit a smaller portion of the payload.

test packetdrill script:
    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
   +0 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR)
   +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0

   +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress)
   +0 > S 0:0(0)  win 65535 <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8>
 +.05 < S. 0:0(0) ack 1 win 6000 <mss 1000,nop,nop,sackOK>
   +0 > . 1:1(0) ack 1

   +0 write(3, ..., 10000) = 10000

   +0 > . 1:2001(2000) ack 1 win 65535
   +0 > . 2001:4001(2000) ack 1 win 65535
   +0 > . 4001:6001(2000) ack 1 win 65535

 +.05 < . 1:1(0) ack 4001 win 1001

and tcpdump show:
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 1:2001, ack 1, win 65535, length 2000
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 2001:4001, ack 1, win 65535, length 2000
192.168.226.67.55 > 192.0.2.1.8080: Flags [P.], seq 4001:5001, ack 1, win 65535, length 1000
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 5001:6001, ack 1, win 65535, length 1000
192.0.2.1.8080 > 192.168.226.67.55: Flags [.], ack 4001, win 1001, length 0
192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 5001:6001, ack 1, win 65535, length 1000
192.168.226.67.55 > 192.0.2.1.8080: Flags [P.], seq 4001:5001, ack 1, win 65535, length 1000

when cient retract window to 1001, send window is [4001,5002],
but TLP send 5001-6001 packet which is out of send window.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/1657532838-20200-1-git-send-email-liyonglong@chinatelecom.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:23:30 +02:00
Kuniyuki Iwashima
4685f16b3a ipv4: Fix data-races around sysctl_fib_notify_on_flag_change.
[ Upstream commit 96b9bd8c6d ]

While reading sysctl_fib_notify_on_flag_change, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 680aea08e7 ("net: ipv4: Emit notification when fib hardware flags are changed")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:52 +02:00
Kuniyuki Iwashima
eaccca7a0b tcp: Fix data-races around sysctl_tcp_reflect_tos.
[ Upstream commit 870e3a634b ]

While reading sysctl_tcp_reflect_tos, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: ac8f1710c1 ("tcp: reflect tos value received in SYN to the socket")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:52 +02:00
Kuniyuki Iwashima
4cc070e0ef tcp: Fix a data-race around sysctl_tcp_comp_sack_nr.
[ Upstream commit 79f55473bf ]

While reading sysctl_tcp_comp_sack_nr, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 9c21d2fc41 ("tcp: add tcp_comp_sack_nr sysctl")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:52 +02:00
Kuniyuki Iwashima
34c9977b4d tcp: Fix a data-race around sysctl_tcp_comp_sack_slack_ns.
[ Upstream commit 22396941a7 ]

While reading sysctl_tcp_comp_sack_slack_ns, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: a70437cc09 ("tcp: add hrtimer slack to sack compression")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:52 +02:00
Kuniyuki Iwashima
6842c94de9 tcp: Fix a data-race around sysctl_tcp_comp_sack_delay_ns.
[ Upstream commit 4866b2b0f7 ]

While reading sysctl_tcp_comp_sack_delay_ns, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 6d82aa2420 ("tcp: add tcp_comp_sack_delay_ns sysctl")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:51 +02:00
Kuniyuki Iwashima
618116a273 net: Fix data-races around sysctl_[rw]mem(_offset)?.
[ Upstream commit 0273954595 ]

While reading these sysctl variables, they can be changed concurrently.
Thus, we need to add READ_ONCE() to their readers.

  - .sysctl_rmem
  - .sysctl_rwmem
  - .sysctl_rmem_offset
  - .sysctl_wmem_offset
  - sysctl_tcp_rmem[1, 2]
  - sysctl_tcp_wmem[1, 2]
  - sysctl_decnet_rmem[1]
  - sysctl_decnet_wmem[1]
  - sysctl_tipc_rmem[1]

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:51 +02:00
Kuniyuki Iwashima
a610feb170 tcp: Fix data-races around sk_pacing_rate.
[ Upstream commit 59bf6c65a0 ]

While reading sysctl_tcp_pacing_(ss|ca)_ratio, they can be changed
concurrently.  Thus, we need to add READ_ONCE() to their readers.

Fixes: 43e122b014 ("tcp: refine pacing rate determination")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:51 +02:00
Kuniyuki Iwashima
dac5644a82 tcp: Fix a data-race around sysctl_tcp_invalid_ratelimit.
[ Upstream commit 2afdbe7b8d ]

While reading sysctl_tcp_invalid_ratelimit, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 032ee42369 ("tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacks")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:49 +02:00
Kuniyuki Iwashima
6f446677eb tcp: Fix a data-race around sysctl_tcp_autocorking.
[ Upstream commit 85225e6f0a ]

While reading sysctl_tcp_autocorking, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: f54b311142 ("tcp: auto corking")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:49 +02:00
Kuniyuki Iwashima
bd07f2e70a tcp: Fix a data-race around sysctl_tcp_min_rtt_wlen.
[ Upstream commit 1330ffacd0 ]

While reading sysctl_tcp_min_rtt_wlen, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: f672258391 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:49 +02:00
Kuniyuki Iwashima
922ca9fd22 tcp: Fix a data-race around sysctl_tcp_min_tso_segs.
[ Upstream commit e0bb4ab9df ]

While reading sysctl_tcp_min_tso_segs, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 95bd09eb27 ("tcp: TSO packets automatic sizing")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:48 +02:00
Kuniyuki Iwashima
c721324afc igmp: Fix data-races around sysctl_igmp_qrv.
[ Upstream commit 8ebcc62c73 ]

While reading sysctl_igmp_qrv, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

This test can be packed into a helper, so such changes will be in the
follow-up series after net is merged into net-next.

  qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);

Fixes: a9fe8e2994 ("ipv4: implement igmp_qrv sysctl to tune igmp robustness variable")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:48 +02:00
Kuniyuki Iwashima
ff2932ac8e tcp: Fix a data-race around sysctl_tcp_challenge_ack_limit.
commit db3815a2fa upstream.

While reading sysctl_tcp_challenge_ack_limit, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 282f23c6ee ("tcp: implement RFC 5961 3.2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:46 +02:00
Kuniyuki Iwashima
a88de75673 tcp: Fix a data-race around sysctl_tcp_limit_output_bytes.
commit 9fb90193fb upstream.

While reading sysctl_tcp_limit_output_bytes, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its reader.

Fixes: 46d3ceabd8 ("tcp: TCP Small Queues")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:46 +02:00
Kuniyuki Iwashima
664a3311e6 tcp: Fix data-races around sysctl_tcp_moderate_rcvbuf.
commit 7804764888 upstream.

While reading sysctl_tcp_moderate_rcvbuf, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:46 +02:00
Wei Wang
927c5cf0ba Revert "tcp: change pingpong threshold to 3"
commit 4d8f24eeed upstream.

This reverts commit 4a41f453be.

This to-be-reverted commit was meant to apply a stricter rule for the
stack to enter pingpong mode. However, the condition used to check for
interactive session "before(tp->lsndtime, icsk->icsk_ack.lrcvtime)" is
jiffy based and might be too coarse, which delays the stack entering
pingpong mode.
We revert this patch so that we no longer use the above condition to
determine interactive session, and also reduce pingpong threshold to 1.

Fixes: 4a41f453be ("tcp: change pingpong threshold to 3")
Reported-by: LemmyHuang <hlm3280@163.com>
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220721204404.388396-1-weiwan@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:45 +02:00
Kuniyuki Iwashima
62e721dee8 tcp: Fix data-races around sysctl_tcp_no_ssthresh_metrics_save.
commit ab1ba21b52 upstream.

While reading sysctl_tcp_no_ssthresh_metrics_save, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 65e6d90168 ("net-tcp: Disable TCP ssthresh metrics cache by default")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:45 +02:00
Kuniyuki Iwashima
aa2ca5b562 tcp: Fix a data-race around sysctl_tcp_nometrics_save.
commit 8499a2454d upstream.

While reading sysctl_tcp_nometrics_save, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:44 +02:00