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Mat Martineau says:
====================
mptcp: Fixes for v6.6
Patch 1 corrects the logic for MP_JOIN tests where 0 RSTs are expected.
Patch 2 ensures MPTCP packets are not incorrectly coalesced in the TCP
backlog queue.
Patch 3 avoids a zero-window probe and associated WARN_ON_ONCE() in an
expected MPTCP reinjection scenario.
Patches 4 & 5 allow an initial MPTCP subflow to be closed cleanly
instead of always sending RST. Associated selftest is updated.
====================
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-0-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The bitmasks for EMAC_PORT_DISABLE and EMAC_PORT_FORWARD r30 commands are
wrong in the driver.
Update the bitmasks of these commands to the correct ones as used by the
ICSSG firmware. These bitmasks are backwards compatible and work with
any ICSSG firmware version.
Fixes: e9b4ece7d74b ("net: ti: icssg-prueth: Add Firmware config and classification APIs.")
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20231018150715.3085380-1-danishanwar@ti.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Recently, we noticed that some RST were wrongly generated when removing
the initial subflow.
This patch makes sure RST are not sent when removing any subflows or any
addresses.
Fixes: c2b2ae3925b6 ("mptcp: handle correctly disconnect() failures")
Cc: stable@vger.kernel.org
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-5-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski says:
====================
net: fix bugs in device netns-move and rename
Daniel reported issues with the uevents generated during netdev
namespace move, if the netdev is getting renamed at the same time.
While the issue that he actually cares about is not fixed here,
there is a bunch of seemingly obvious other bugs in this code.
Fix the purely networking bugs while the discussion around
the uevent fix is still ongoing.
====================
Link: https://lore.kernel.org/r/20231018013817.2391509-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When closing the first subflow, the MPTCP protocol unconditionally
calls tcp_disconnect(), which in turn generates a reset if the subflow
is established.
That is unexpected and different from what MPTCP does with MPJ
subflows, where resets are generated only on FASTCLOSE and other edge
scenarios.
We can't reuse for the first subflow the same code in place for MPJ
subflows, as MPTCP clean them up completely via a tcp_close() call,
while must keep the first subflow socket alive for later re-usage, due
to implementation constraints.
This patch adds a new helper __mptcp_subflow_disconnect() that
encapsulates, a logic similar to tcp_close, issuing a reset only when
the MPTCP_CF_FASTCLOSE flag is set, and performing a clean shutdown
otherwise.
Fixes: c2b2ae3925b6 ("mptcp: handle correctly disconnect() failures")
Cc: stable@vger.kernel.org
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-4-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
With CONFIG_TI_K3_AM65_CPSW_NUSS=y and CONFIG_TI_ICSSG_PRUETH=m,
k3-cppi-desc-pool.o is linked to a module and also to vmlinux even though
the expected CFLAGS are different between builtins and modules.
The build system is complaining about the following:
k3-cppi-desc-pool.o is added to multiple modules: icssg-prueth
ti-am65-cpsw-nuss
Introduce the new module, k3-cppi-desc-pool, to provide the common
functions to ti-am65-cpsw-nuss and icssg-prueth.
Fixes: 128d5874c082 ("net: ti: icssg-prueth: Add ICSSG ethernet driver")
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Link: https://lore.kernel.org/r/20231018064936.3146846-1-danishanwar@ti.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add selftest for fixes around naming netdevs and namespaces.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Christoph reported that the MPTCP protocol can find the subflow-level
write queue unexpectedly not empty while crafting a zero-window probe,
hitting a warning:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 188 at net/mptcp/protocol.c:1312 mptcp_sendmsg_frag+0xc06/0xe70
Modules linked in:
CPU: 0 PID: 188 Comm: kworker/0:2 Not tainted 6.6.0-rc2-g1176aa719d7a #47
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:mptcp_sendmsg_frag+0xc06/0xe70 net/mptcp/protocol.c:1312
RAX: 47d0530de347ff6a RBX: 47d0530de347ff6b RCX: ffff8881015d3c00
RDX: ffff8881015d3c00 RSI: 47d0530de347ff6b RDI: 47d0530de347ff6b
RBP: 47d0530de347ff6b R08: ffffffff8243c6a8 R09: ffffffff82042d9c
R10: 0000000000000002 R11: ffffffff82056850 R12: ffff88812a13d580
R13: 0000000000000001 R14: ffff88812b375e50 R15: ffff88812bbf3200
FS: 0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000695118 CR3: 0000000115dfc001 CR4: 0000000000170ef0
Call Trace:
<TASK>
__subflow_push_pending+0xa4/0x420 net/mptcp/protocol.c:1545
__mptcp_push_pending+0x128/0x3b0 net/mptcp/protocol.c:1614
mptcp_release_cb+0x218/0x5b0 net/mptcp/protocol.c:3391
release_sock+0xf6/0x100 net/core/sock.c:3521
mptcp_worker+0x6e8/0x8f0 net/mptcp/protocol.c:2746
process_scheduled_works+0x341/0x690 kernel/workqueue.c:2630
worker_thread+0x3a7/0x610 kernel/workqueue.c:2784
kthread+0x143/0x180 kernel/kthread.c:388
ret_from_fork+0x4d/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:304
</TASK>
The root cause of the issue is that expectations are wrong: e.g. due
to MPTCP-level re-injection we can hit the critical condition.
Explicitly avoid the zero-window probe when the subflow write queue
is not empty and drop the related warnings.
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/444
Fixes: f70cad1085d1 ("mptcp: stop relying on tcp_tx_skb_cache")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-3-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Florian Westphal says:
====================
netfilter: updates for net
First patch, from Phil Sutter, reduces number of audit notifications
when userspace requests to re-set stateful objects.
This change also comes with a selftest update.
Second patch, also from Phil, moves the nftables audit selftest
to its own netns to avoid interference with the init netns.
Third patch, from Pablo Neira, fixes an inconsistency with the "rbtree"
set backend: When set element X has expired, a request to delete element
X should fail (like with all other backends).
Finally, patch four, also from Pablo, reverts a recent attempt to speed
up abort of a large pending update with the "pipapo" set backend.
It could cause stray references to remain in the set, which then
results in a double-free.
* tag 'nf-23-10-18' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nf_tables: revert do not remove elements if set backend implements .abort
netfilter: nft_set_rbtree: .deactivate fails if element has expired
selftests: netfilter: Run nft_audit.sh in its own netns
netfilter: nf_tables: audit log object reset once per table
====================
Link: https://lore.kernel.org/r/20231018125605.27299-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The altname nodes are currently not moved to the new netns
when netdevice itself moves:
[ ~]# ip netns add test
[ ~]# ip -netns test link add name eth0 type dummy
[ ~]# ip -netns test link property add dev eth0 altname some-name
[ ~]# ip -netns test link show dev some-name
2: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 1e:67:ed:19:3d:24 brd ff:ff:ff:ff:ff:ff
altname some-name
[ ~]# ip -netns test link set dev eth0 netns 1
[ ~]# ip link
...
3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff
altname some-name
[ ~]# ip li show dev some-name
Device "some-name" does not exist.
Remove them from the hash table when device is unlisted
and add back when listed again.
Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The MPTCP protocol can acquire the subflow-level socket lock and
cause the tcp backlog usage. When inserting new skbs into the
backlog, the stack will try to coalesce them.
Currently, we have no check in place to ensure that such coalescing
will respect the MPTCP-level DSS, and that may cause data stream
corruption, as reported by Christoph.
Address the issue by adding the relevant admission check for coalescing
in tcp_add_backlog().
Note the issue is not easy to reproduce, as the MPTCP protocol tries
hard to avoid acquiring the subflow-level socket lock.
Fixes: 648ef4b88673 ("mptcp: Implement MPTCP receive path")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/420
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-2-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Johannes Berg says:
====================
A few more fixes:
* prevent value bounce/glitch in rfkill GPIO probe
* fix lockdep report in rfkill
* fix error path leak in mac80211 key handling
* use system_unbound_wq for wiphy work since it
can take longer
* tag 'wireless-2023-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless:
net: rfkill: reduce data->mtx scope in rfkill_fop_open
net: rfkill: gpio: prevent value glitch during probe
wifi: mac80211: fix error path key leak
wifi: cfg80211: use system_unbound_wq for wiphy work
====================
Link: https://lore.kernel.org/r/20231018071041.8175-2-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
nf_tables_abort_release() path calls nft_set_elem_destroy() for
NFT_MSG_NEWSETELEM which releases the element, however, a reference to
the element still remains in the working copy.
Fixes: ebd032fa8818 ("netfilter: nf_tables: do not remove elements if set backend implements .abort")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Altnames are accessed under RCU (dev_get_by_name_rcu())
but freed by kfree() with no synchronization point.
Each node has one or two allocations (node and a variable-size
name, sometimes the name is netdev->name). Adding rcu_heads
here is a bit tedious. Besides most code which unlists the names
already has rcu barriers - so take the simpler approach of adding
synchronize_rcu(). Note that the one on the unregistration path
(which matters more) is removed by the next fix.
Fixes: ff92741270bf ("net: introduce name_node struct to be used in hashlist")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The commit mentioned below was more tolerant with the number of RST seen
during a test because in some uncontrollable situations, multiple RST
can be generated.
But it was not taking into account the case where no RST are expected:
this validation was then no longer reporting issues for the 0 RST case
because it is not possible to have less than 0 RST in the counter. This
patch fixes the issue by adding a specific condition.
Fixes: 6bf41020b72b ("selftests: mptcp: update and extend fastclose test-cases")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-1-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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