commit e32d262c89e2b22cb0640223f953b548617ed8a6 upstream.
Bugged peer implementation can send corrupted DSS options, consistently
hitting a few warning in the data path. Use DEBUG_NET assertions, to
avoid the splat on some builds and handle consistently the error, dumping
related MIBs and performing fallback and/or reset according to the
subflow type.
Fixes: 6771bfd9ee24 ("mptcp: update mptcp ack sequence from work queue")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20241008-net-mptcp-fallback-fixes-v1-1-c6fb8e93e551@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Conflicts in mib.[ch], because commit 104125b82e5c ("mptcp: add mib
for infinite map sending") is linked to a new feature, not available
in this version. Resolving the conflicts is easy, simply adding the
new lines declaring the new "DSS corruptions" MIB entries.
Also removed in protocol.c and subflow.c all DEBUG_NET_WARN_ON_ONCE
because they are not defined in this version: enough with the MIB
counters that have been added in this commit. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0530020a7c8f2204e784f0dbdc882bbd961fdbde upstream.
This patch adds a new member allow_infinite_fallback in mptcp_sock,
which is initialized to 'true' when the connection begins and is set
to 'false' on any retransmit or successful MP_JOIN. Only do infinite
mapping fallback if there is a single subflow AND there have been no
retransmissions AND there have never been any MP_JOINs.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e32d262c89e2 ("mptcp: handle consistently DSS corruption")
[ Conflicts in protocol.c, because commit 3e5014909b56 ("mptcp: cleanup
MPJ subflow list handling") is not in this version. This commit is
linked to a new feature, changing the context around. The new line
can still be added at the same place.
Conflicts in protocol.h, because commit 4f6e14bd19d6 ("mptcp: support
TCP_CORK and TCP_NODELAY") is not in this version. This commit is
linked to a new feature, changing the context around. The new line can
still be added at the same place.
Conflicts in subflow.c, because commit 0348c690ed37 ("mptcp: add the
fallback check") is not in this version. This commit is linked to a
new feature, changing the context around. The new line can still be
added at the same place.
Extra conflicts in v5.10, because the context has been changed. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cb41b195e634d3f1ecfcd845314e64fd4bb3c7aa upstream.
pr_debug() have been added in various places in MPTCP code to help
developers to debug some situations. With the dynamic debug feature, it
is easy to enable all or some of them, and asks users to reproduce
issues with extra debug.
Many of these pr_debug() don't end with a new line, while no 'pr_cont()'
are used in MPTCP code. So the goal was not to display multiple debug
messages on one line: they were then not missing the '\n' on purpose.
Not having the new line at the end causes these messages to be printed
with a delay, when something else needs to be printed. This issue is not
visible when many messages need to be printed, but it is annoying and
confusing when only specific messages are expected, e.g.
# echo "func mptcp_pm_add_addr_echoed +fmp" \
> /sys/kernel/debug/dynamic_debug/control
# ./mptcp_join.sh "signal address"; \
echo "$(awk '{print $1}' /proc/uptime) - end"; \
sleep 5s; \
echo "$(awk '{print $1}' /proc/uptime) - restart"; \
./mptcp_join.sh "signal address"
013 signal address
(...)
10.75 - end
15.76 - restart
013 signal address
[ 10.367935] mptcp:mptcp_pm_add_addr_echoed: MPTCP: msk=(...)
(...)
=> a delay of 5 seconds: printed with a 10.36 ts, but after 'restart'
which was printed at the 15.76 ts.
The 'Fixes' tag here below points to the first pr_debug() used without
'\n' in net/mptcp. This patch could be split in many small ones, with
different Fixes tag, but it doesn't seem worth it, because it is easy to
re-generate this patch with this simple 'sed' command:
git grep -l pr_debug -- net/mptcp |
xargs sed -i "s/\(pr_debug(\".*[^n]\)\(\"[,)]\)/\1\\\n\2/g"
So in case of conflicts, simply drop the modifications, and launch this
command.
Fixes: f870fa0b5768 ("mptcp: Add MPTCP socket stubs")
Cc: stable@vger.kernel.org
Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240826-net-mptcp-close-extra-sf-fin-v1-4-905199fe1172@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ As mentioned above, conflicts were expected, and resolved by using the
'sed' command which is visible above. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2a1f596ebb23eadc0f9b95a8012e18ef76295fc8 upstream.
The 'mptcp_subflow_context' structure has two items related to the
backup flags:
- 'backup': the subflow has been marked as backup by the other peer
- 'request_bkup': the backup flag has been set by the host
Looking only at the 'backup' flag can make sense in some cases, but it
is not the behaviour of the default packet scheduler when selecting
paths.
As explained in the commit b6a66e521a20 ("mptcp: sched: check both
directions for backup"), the packet scheduler should look at both flags,
because that was the behaviour from the beginning: the 'backup' flag was
set by accident instead of the 'request_bkup' one. Now that the latter
has been fixed, get_retrans() needs to be adapted as well.
Fixes: b6a66e521a20 ("mptcp: sched: check both directions for backup")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240826-net-mptcp-close-extra-sf-fin-v1-3-905199fe1172@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b6a66e521a2032f7fcba2af5a9bcbaeaa19b7ca3 upstream.
The 'mptcp_subflow_context' structure has two items related to the
backup flags:
- 'backup': the subflow has been marked as backup by the other peer
- 'request_bkup': the backup flag has been set by the host
Before this patch, the scheduler was only looking at the 'backup' flag.
That can make sense in some cases, but it looks like that's not what we
wanted for the general use, because either the path-manager was setting
both of them when sending an MP_PRIO, or the receiver was duplicating
the 'backup' flag in the subflow request.
Note that the use of these two flags in the path-manager are going to be
fixed in the next commits, but this change here is needed not to modify
the behaviour.
Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[ Conflicts in protocol.c, because the context has changed in commit
3ce0852c86b9 ("mptcp: enforce HoL-blocking estimation") and in commit
33d41c9cd74c ("mptcp: more accurate timeout"), which are not in this
version. This commit is unrelated to this modification.
Note that the tracepoint is not in this version, see commit
e10a98920976 ("mptcp: add tracepoint in mptcp_subflow_get_send"). ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8031b58c3a9b1db3ef68b3bd749fbee2e1e1aaa3 upstream.
This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt
is properly initialized on connect"). It turns out that syzkaller can
trigger the retransmit after fallback and before processing any other
incoming packet - so that snd_una is still left uninitialized.
Address the issue explicitly initializing snd_una together with snd_nxt
and write_seq.
Suggested-by: Mat Martineau <martineau@kernel.org>
Fixes: 8fd738049ac3 ("mptcp: fallback in case of simultaneous connect")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/485
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240607-upstream-net-20240607-misc-fixes-v1-1-1ab9ddfa3d00@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Conflicts in protocol.c, similar to the ones from commit 99951b62bf20
("mptcp: ensure snd_nxt is properly initialized on connect"), with the
same resolution. Note that in this version, 'snd_una' is an atomic64
type, so use atomic64_set() instead, as it is done everywhere else. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fb7a0d334894206ae35f023a82cad5a290fd7386 upstream.
Christoph reported a splat hinting at a corrupted snd_una:
WARNING: CPU: 1 PID: 38 at net/mptcp/protocol.c:1005 __mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005
Modules linked in:
CPU: 1 PID: 38 Comm: kworker/1:1 Not tainted 6.9.0-rc1-gbbeac67456c9 #59
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:__mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005
Code: be 06 01 00 00 bf 06 01 00 00 e8 a8 12 e7 fe e9 00 fe ff ff e8
8e 1a e7 fe 0f b7 ab 3e 02 00 00 e9 d3 fd ff ff e8 7d 1a e7 fe
<0f> 0b 4c 8b bb e0 05 00 00 e9 74 fc ff ff e8 6a 1a e7 fe 0f 0b e9
RSP: 0018:ffffc9000013fd48 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff8881029bd280 RCX: ffffffff82382fe4
RDX: ffff8881003cbd00 RSI: ffffffff823833c3 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: fefefefefefefeff R12: ffff888138ba8000
R13: 0000000000000106 R14: ffff8881029bd908 R15: ffff888126560000
FS: 0000000000000000(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f604a5dae38 CR3: 0000000101dac002 CR4: 0000000000170ef0
Call Trace:
<TASK>
__mptcp_clean_una_wakeup net/mptcp/protocol.c:1055 [inline]
mptcp_clean_una_wakeup net/mptcp/protocol.c:1062 [inline]
__mptcp_retrans+0x7f/0x7e0 net/mptcp/protocol.c:2615
mptcp_worker+0x434/0x740 net/mptcp/protocol.c:2767
process_one_work+0x1e0/0x560 kernel/workqueue.c:3254
process_scheduled_works kernel/workqueue.c:3335 [inline]
worker_thread+0x3c7/0x640 kernel/workqueue.c:3416
kthread+0x121/0x170 kernel/kthread.c:388
ret_from_fork+0x44/0x50 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
</TASK>
When fallback to TCP happens early on a client socket, snd_nxt
is not yet initialized and any incoming ack will copy such value
into snd_una. If the mptcp worker (dumbly) tries mptcp-level
re-injection after such ack, that would unconditionally trigger a send
buffer cleanup using 'bad' snd_una values.
We could easily disable re-injection for fallback sockets, but such
dumb behavior already helped catching a few subtle issues and a very
low to zero impact in practice.
Instead address the issue always initializing snd_nxt (and write_seq,
for consistency) at connect time.
Fixes: 8fd738049ac3 ("mptcp: fallback in case of simultaneous connect")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/485
Tested-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240429-upstream-net-20240429-mptcp-snd_nxt-init-connect-v1-1-59ceac0a7dcb@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ snd_nxt field is not available in v5.10.y: before, only write_seq was
used, see commit eaa2ffabfc35 ("mptcp: introduce MPTCP snd_nxt") for
more details about that. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 upstream.
Current MPTCP servers increment MPTcpExtMPCapableFallbackACK when they
accept non-MPC connections. As reported by Christoph, this is "surprising"
because the counter might become greater than MPTcpExtMPCapableSYNRX.
MPTcpExtMPCapableFallbackACK counter's name suggests it should only be
incremented when a connection was seen using MPTCP options, then a
fallback to TCP has been done. Let's do that by incrementing it when
the subflow context of an inbound MPC connection attempt is dropped.
Also, update mptcp_connect.sh kselftest, to ensure that the
above MIB does not increment in case a pure TCP client connects to a
MPTCP server.
Fixes: fc518953bc9c ("mptcp: add and use MIB counter infrastructure")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/449
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240329-upstream-net-20240329-fallback-mib-v1-1-324a8981da48@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 10048689def7e40a4405acda16fdc6477d4ecc5c upstream.
when MPTCP server accepts an incoming connection, it clones its listener
socket. However, the pointer to 'inet_opt' for the new socket has the same
value as the original one: as a consequence, on program exit it's possible
to observe the following splat:
BUG: KASAN: double-free in inet_sock_destruct+0x54f/0x8b0
Free of addr ffff888485950880 by task swapper/25/0
CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Not tainted 6.8.0-rc1+ #609
Hardware name: Supermicro SYS-6027R-72RF/X9DRH-7TF/7F/iTF/iF, BIOS 3.0 07/26/2013
Call Trace:
<IRQ>
dump_stack_lvl+0x32/0x50
print_report+0xca/0x620
kasan_report_invalid_free+0x64/0x90
__kasan_slab_free+0x1aa/0x1f0
kfree+0xed/0x2e0
inet_sock_destruct+0x54f/0x8b0
__sk_destruct+0x48/0x5b0
rcu_do_batch+0x34e/0xd90
rcu_core+0x559/0xac0
__do_softirq+0x183/0x5a4
irq_exit_rcu+0x12d/0x170
sysvec_apic_timer_interrupt+0x6b/0x80
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20
RIP: 0010:cpuidle_enter_state+0x175/0x300
Code: 30 00 0f 84 1f 01 00 00 83 e8 01 83 f8 ff 75 e5 48 83 c4 18 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc fb 45 85 ed <0f> 89 60 ff ff ff 48 c1 e5 06 48 c7 43 18 00 00 00 00 48 83 44 2b
RSP: 0018:ffff888481cf7d90 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88887facddc8 RCX: 0000000000000000
RDX: 1ffff1110ff588b1 RSI: 0000000000000019 RDI: ffff88887fac4588
RBP: 0000000000000004 R08: 0000000000000002 R09: 0000000000043080
R10: 0009b02ea273363f R11: ffff88887fabf42b R12: ffffffff932592e0
R13: 0000000000000004 R14: 0000000000000000 R15: 00000022c880ec80
cpuidle_enter+0x4a/0xa0
do_idle+0x310/0x410
cpu_startup_entry+0x51/0x60
start_secondary+0x211/0x270
secondary_startup_64_no_verify+0x184/0x18b
</TASK>
Allocated by task 6853:
kasan_save_stack+0x1c/0x40
kasan_save_track+0x10/0x30
__kasan_kmalloc+0xa6/0xb0
__kmalloc+0x1eb/0x450
cipso_v4_sock_setattr+0x96/0x360
netlbl_sock_setattr+0x132/0x1f0
selinux_netlbl_socket_post_create+0x6c/0x110
selinux_socket_post_create+0x37b/0x7f0
security_socket_post_create+0x63/0xb0
__sock_create+0x305/0x450
__sys_socket_create.part.23+0xbd/0x130
__sys_socket+0x37/0xb0
__x64_sys_socket+0x6f/0xb0
do_syscall_64+0x83/0x160
entry_SYSCALL_64_after_hwframe+0x6e/0x76
Freed by task 6858:
kasan_save_stack+0x1c/0x40
kasan_save_track+0x10/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x12c/0x1f0
kfree+0xed/0x2e0
inet_sock_destruct+0x54f/0x8b0
__sk_destruct+0x48/0x5b0
subflow_ulp_release+0x1f0/0x250
tcp_cleanup_ulp+0x6e/0x110
tcp_v4_destroy_sock+0x5a/0x3a0
inet_csk_destroy_sock+0x135/0x390
tcp_fin+0x416/0x5c0
tcp_data_queue+0x1bc8/0x4310
tcp_rcv_state_process+0x15a3/0x47b0
tcp_v4_do_rcv+0x2c1/0x990
tcp_v4_rcv+0x41fb/0x5ed0
ip_protocol_deliver_rcu+0x6d/0x9f0
ip_local_deliver_finish+0x278/0x360
ip_local_deliver+0x182/0x2c0
ip_rcv+0xb5/0x1c0
__netif_receive_skb_one_core+0x16e/0x1b0
process_backlog+0x1e3/0x650
__napi_poll+0xa6/0x500
net_rx_action+0x740/0xbb0
__do_softirq+0x183/0x5a4
The buggy address belongs to the object at ffff888485950880
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
64-byte region [ffff888485950880, ffff8884859508c0)
The buggy address belongs to the physical page:
page:0000000056d1e95e refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888485950700 pfn:0x485950
flags: 0x57ffffc0000800(slab|node=1|zone=2|lastcpupid=0x1fffff)
page_type: 0xffffffff()
raw: 0057ffffc0000800 ffff88810004c640 ffffea00121b8ac0 dead000000000006
raw: ffff888485950700 0000000000200019 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888485950780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff888485950800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff888485950880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
^
ffff888485950900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff888485950980: 00 00 00 00 00 01 fc fc fc fc fc fc fc fc fc fc
Something similar (a refcount underflow) happens with CALIPSO/IPv6. Fix
this by duplicating IP / IPv6 options after clone, so that
ip{,6}_sock_destruct() doesn't end up freeing the same memory area twice.
Fixes: cf7da0d66cc1 ("mptcp: Create SUBFLOW socket for incoming connections")
Cc: stable@vger.kernel.org
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-8-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
