The 'state->im' value will always be non-zero after
the 'while' statement, so the check can be removed.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230912084100.1502379-1-Ilia.Gavrilov@infotecs.ruSigned-off-by: Paolo Abeni <pabeni@redhat.com>

The 'state->im' value will always be non-zero after
the 'while' statement, so the check can be removed.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.
Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230912084039.1501984-1-Ilia.Gavrilov@infotecs.ruSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Eric Dumazet says:

====================
udp: round of data-races fixes

This series is inspired by multiple syzbot reports.

Many udp fields reads or writes are racy.

Add a proper udp->udp_flags and move there all
flags needing atomic safety.

Also add missing READ_ONCE()/WRITE_ONCE() when
lockless readers need access to specific fields.
====================

Link: https://lore.kernel.org/r/20230912091730.1591459-1-edumazet@google.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

udp->pcflag, udp->pcslen and udp->pcrlen reads/writes are racy.

Move udp->pcflag to udp->udp_flags for atomicity,
and add READ_ONCE()/WRITE_ONCE() annotations for pcslen and pcrlen.

Fixes: ba4e58ec ("[NET]: Supporting UDP-Lite (RFC 3828) in Linux")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

This flag is set but never read, we can remove it.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

syzbot/KCSAN complained about UDP_ENCAP_L2TPINUDP setsockopt() racing.

Add READ_ONCE()/WRITE_ONCE() to document races on this lockless field.

syzbot report was:
BUG: KCSAN: data-race in udp_lib_setsockopt / udp_lib_setsockopt

read-write to 0xffff8881083603fa of 1 bytes by task 16557 on cpu 0:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff8881083603fa of 1 bytes by task 16554 on cpu 1:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -> 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16554 Comm: syz-executor.5 Not tainted 6.5.0-rc7-syzkaller-00004-gf7757129 #0

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Move udp->encap_enabled to udp->udp_flags.

Add udp_test_and_set_bit() helper to allow lockless
udp_tunnel_encap_enable() implementation.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

These are read locklessly, move them to udp_flags to fix data-races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

UDP_ENCAP_ESPINUDP_NON_IKE setsockopt() writes over up->encap_rcv
while other cpus read it.

Fixes: 067b207b ("[UDP]: Cleanup UDP encapsulation code")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

syzbot reported that udp->gro_enabled can be read locklessly.
Use one atomic bit from udp->udp_flags.

Fixes: e20cf8d3 ("udp: implement GRO for plain UDP sockets.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

syzbot reported that udp->no_check6_rx can be read locklessly.
Use one atomic bit from udp->udp_flags.

Fixes: 1c19448c ("net: Make enabling of zero UDP6 csums more restrictive")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

syzbot reported that udp->no_check6_tx can be read locklessly.
Use one atomic bit from udp->udp_flags

Fixes: 1c19448c ("net: Make enabling of zero UDP6 csums more restrictive")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

According to syzbot, it is time to use proper atomic flags
for various UDP flags.

Add udp_flags field, and convert udp->corkflag to first
bit in it.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Check if update_wo_rx_stats function pointer is properly set in
mtk_wed_update_rx_stats routine before accessing it.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/b0d233386e059bccb59f18f69afb79a7806e5ded.1694507226.git.lorenzo@kernel.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Similar to ethernet ports, rely on mtk_pse_port definitions for
pse wdma ports as well.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/b86bdb717e963e3246c1dec5f736c810703cf056.1694506814.git.lorenzo@kernel.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Move similar code of accessing MDIO bus from txgbe/ngbe to libwx.
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230912031424.721386-1-jiawenwu@trustnetic.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

This is based on alx driver commit 881d0327 ("net: alx: Work around
the DMA RX overflow issue").

The alx and atl1c drivers had RX overflow error which was why a custom
allocator was created to avoid certain addresses. The simpler workaround
then created for alx driver, but not for atl1c due to lack of tester.

Instead of using a custom allocator, check the allocated skb address and
use skb_reserve() to move away from problematic 0x...fc0 address.

Tested on AR8131 on Acer 4540.
Signed-off-by: Sieng-Piaw Liew <liew.s.piaw@gmail.com>
Link: https://lore.kernel.org/r/20230912010711.12036-1-liew.s.piaw@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Arseniy Krasnov says:

====================
vsock: handle writes to shutdowned socket

this small patchset adds POSIX compliant behaviour on writes to the
socket which was shutdowned with 'shutdown()' (both sides - local with
SHUT_WR flag, peer - with SHUT_RD flag). According POSIX we must send
SIGPIPE in such cases (but SIGPIPE is not send when MSG_NOSIGNAL is set).

First patch is implemented in the same way as net/ipv4/tcp.c:tcp_sendmsg_locked().
It uses 'sk_stream_error()' function which handles EPIPE error. Another
way is to use code from net/unix/af_unix.c:unix_stream_sendmsg() where
same logic from 'sk_stream_error()' is implemented "from scratch", but
it doesn't check 'sk_err' field. I think error from this field has more
priority to be returned from syscall. So I guess it is better to reuse
currently implemented 'sk_stream_error()' function.

Test is also added.
====================

Link: https://lore.kernel.org/r/20230911202027.1928574-1-avkrasnov@salutedevices.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

This adds two tests for 'shutdown()' call. It checks that SIGPIPE is
sent when MSG_NOSIGNAL is not set and vice versa. Both flags SHUT_WR
and SHUT_RD are tested.
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

POSIX requires to send SIGPIPE on write to SOCK_STREAM socket which was
shutdowned with SHUT_WR flag or its peer was shutdowned with SHUT_RD
flag. Also we must not send SIGPIPE if MSG_NOSIGNAL flag is set.
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Pedro Tammela says:

====================
selftests/tc-testing: add tests covering classid

Patches 1-3 add missing tests covering classid behaviour on tdc for cls_fw,
cls_route and cls_fw. This behaviour was recently fixed by valis[0].

Patch 4 comes from the development done in the previous patches as it turns out
cls_route never returns meaningful errors.

[0] https://lore.kernel.org/all/20230729123202.72406-1-jhs@mojatatu.com/

v2->v3: https://lore.kernel.org/all/20230825155148.659895-1-pctammela@mojatatu.com/
   - Added changes that were left in the working tree (Jakub)
   - Fixed two typos in commit message titles
   - Added Victor tags

v1->v2: https://lore.kernel.org/all/20230818163544.351104-1-pctammela@mojatatu.com/
   - Drop u32 updates
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Use netlink extended ack and parsing policies to return more meaningful
errors instead of the relying solely on errnos.
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As discussed in '3044b16e', cls_u32 was handling the use of classid
incorrectly. Add a test to check if it's conforming to the correct
behaviour.
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As discussed in 'b80b829e', cls_route was handling the use of classid
incorrectly. Add a test to check if it's conforming to the correct
behaviour.
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As discussed in '76e42ae8', cls_fw was handling the use of classid
incorrectly. Add a few tests to check if it's conforming to the correct
behaviour.
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Pavan Chebbi pavan.chebbi@broadcom.com
Signed-off-by: Siva Reddy Kallam <siva.kallam@broadcom.com>
Signed-off-by: Prashant Sreedharan <prashant.sreedharan@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use devm_kasprintf() instead of hand writing it.
This is less verbose and less error prone.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Tony Nguyen says:

====================
Intel Wired LAN Driver Updates 2023-09-11 (i40e, iavf)

This series contains updates to i40e and iavf drivers.

Andrii ensures all VSIs are cleaned up for remove in i40e.

Brett reworks logic for setting promiscuous mode that can, currently, cause
incorrect states on iavf.
---
v2:
 - Remove redundant i40e_vsi_free_q_vectors() and kfree() calls (patch 1)

v1: https://lore.kernel.org/netdev/20230905180521.887861-1-anthony.l.nguyen@intel.com/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
tcp: backlog processing optims

First patches are mostly preparing the ground for the last one.

Last patch of the series implements sort of ACK reduction
only for the cases a TCP receiver is under high stress,
which happens for high throughput flows.

This gives us a ~20% increase of single TCP flow (100Gbit -> 120Gbit)
====================

Link: https://lore.kernel.org/r/20230911170531.828100-1-edumazet@google.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

This idea came after a particular workload requested
the quickack attribute set on routes, and a performance
drop was noticed for large bulk transfers.

For high throughput flows, it is best to use one cpu
running the user thread issuing socket system calls,
and a separate cpu to process incoming packets from BH context.
(With TSO/GRO, bottleneck is usually the 'user' cpu)

Problem is the user thread can spend a lot of time while holding
the socket lock, forcing BH handler to queue most of incoming
packets in the socket backlog.

Whenever the user thread releases the socket lock, it must first
process all accumulated packets in the backlog, potentially
adding latency spikes. Due to flood mitigation, having too many
packets in the backlog increases chance of unexpected drops.

Backlog processing unfortunately shifts a fair amount of cpu cycles
from the BH cpu to the 'user' cpu, thus reducing max throughput.

This patch takes advantage of the backlog processing,
and the fact that ACK are mostly cumulative.

The idea is to detect we are in the backlog processing
and defer all eligible ACK into a single one,
sent from tcp_release_cb().

This saves cpu cycles on both sides, and network resources.

Performance of a single TCP flow on a 200Gbit NIC:

- Throughput is increased by 20% (100Gbit -> 120Gbit).
- Number of generated ACK per second shrinks from 240,000 to 40,000.
- Number of backlog drops per second shrinks from 230 to 0.

Benchmark context:
 - Regular netperf TCP_STREAM (no zerocopy)
 - Intel(R) Xeon(R) Platinum 8481C (Saphire Rapids)
 - MAX_SKB_FRAGS = 17 (~60KB per GRO packet)

This feature is guarded by a new sysctl, and enabled by default:
 /proc/sys/net/ipv4/tcp_backlog_ack_defer
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

__sk_flush_backlog() / sk_flush_backlog() are used
when TCP recvmsg()/sendmsg() process large chunks,
to not let packets in the backlog too long.

It makes sense to call tcp_release_cb() to also
process actions held in sk->sk_tsq_flags for smoother
scheduling.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

sock_release_ownership() should only be called by user
owning the socket lock.

After prior commit, we can remove one condition.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

This partially reverts c3f9b018 ("tcp: tcp_release_cb()
should release socket ownership").

prequeue has been removed by Florian in commit e7942d06
("tcp: remove prequeue support")

__tcp_checksum_complete_user() being gone, we no longer
have to release socket ownership in tcp_release_cb().

This is a prereq for third patch in the series
("net: call prot->release_cb() when processing backlog").
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Use bitmap_zalloc() and bitmap_free() instead of hand-writing them.
It is less verbose and it improves the type checking and semantic.

While at it, add missing header inclusion (should be bitops.h,
but with the above change it becomes bitmap.h).
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230911131618.4159437-1-andriy.shevchenko@linux.intel.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Since commit 1202cdd6("Remove DECnet support from kernel") has been
merged, all callers pass in the initial_ref value of 1 when they call
dst_alloc(). Therefore, remove initial_ref when the dst_alloc() is
declared and replace initial_ref with 1 in dst_alloc().
Also when all callers call dst_init(), the value of initial_ref is 1.
Therefore, remove the input parameter initial_ref of the dst_init() and
replace initial_ref with the value 1 in dst_init.
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Link: https://lore.kernel.org/r/20230911125045.346390-1-shaozhengchao@huawei.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

MD Danish Anwar says:

====================
Add support for ICSSG on AM64x EVM

This series adds support for ICSSG driver on AM64x EVM.

First patch of the series adds compatible for AM64x EVM in icssg-prueth
dt binding. Second patch adds support for AM64x compatible in the ICSSG
driver.

This series addresses comments on [v1] (which was posted as RFC).
This series is based on the latest net-next/main. This series has no
dependency.

Changes from v1 to v2:
*) Made the compatible list in patch 1 alphanumerically ordered as asked
   by Krzysztof.
*) Dropped the RFC tag.
*) Added RB tags of Andrew and Roger.

[v1] https://lore.kernel.org/all/20230830113724.1228624-1-danishanwar@ti.com/
====================

Link: https://lore.kernel.org/r/20230911054308.2163076-1-danishanwar@ti.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Add AM64x ICSSG support which is similar to am65x SR2.0, but required:
- all ring configured in exposed ring mode
- always fill both original and buffer fields in cppi5 desc
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Add compatible for AM64x in icssg-prueth dt bindings. AM64x supports
ICSSG similar to AM65x SR2.0.
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Currently when configuring promiscuous mode on the AVF we detect a
change in the netdev->flags. We use IFF_PROMISC and IFF_ALLMULTI to
determine whether or not we need to request/release promiscuous mode
and/or multicast promiscuous mode. The problem is that the AQ calls for
setting/clearing promiscuous/multicast mode are treated separately. This
leads to a case where we can trigger two promiscuous mode AQ calls in
a row with the incorrect state. To fix this make a few changes.

Use IAVF_FLAG_AQ_CONFIGURE_PROMISC_MODE instead of the previous
IAVF_FLAG_AQ_[REQUEST|RELEASE]_[PROMISC|ALLMULTI] flags.

In iavf_set_rx_mode() detect if there is a change in the
netdev->flags in comparison with adapter->flags and set the
IAVF_FLAG_AQ_CONFIGURE_PROMISC_MODE aq_required bit. Then in
iavf_process_aq_command() only check for IAVF_FLAG_CONFIGURE_PROMISC_MODE
and call iavf_set_promiscuous() if it's set.

In iavf_set_promiscuous() check again to see which (if any) promiscuous
mode bits have changed when comparing the netdev->flags with the
adapter->flags. Use this to set the flags which get sent to the PF
driver.

Add a spinlock that is used for updating current_netdev_promisc_flags
and only allows one promiscuous mode AQ at a time.

[1] Fixes the fact that we will only have one AQ call in the aq_required
queue at any one time.

[2] Streamlines the change in promiscuous mode to only set one AQ
required bit.

[3] This allows us to keep track of the current state of the flags and
also makes it so we can take the most recent netdev->flags promiscuous
mode state.

[4] This fixes the problem where a change in the netdev->flags can cause
IAVF_FLAG_AQ_CONFIGURE_PROMISC_MODE to be set in iavf_set_rx_mode(),
but cleared in iavf_set_promiscuous() before the change is ever made via
AQ call.

Fixes: 47d34839 ("i40evf: Add driver support for promiscuous mode")
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Instead of freeing memory of a single VSI, make sure
the memory for all VSIs is cleared before releasing VSIs.
Add releasing of their resources in a loop with the iteration
number equal to the number of allocated VSIs.

Fixes: 41c445ff ("i40e: main driver core")
Signed-off-by: Andrii Staikov <andrii.staikov@intel.com>
Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>