This was left as TODO in commit 01e23b2b ("net: enetc: add support
for preemptible traffic classes") since it's relatively complicated.

Where this makes a difference is with a configuration as follows:

ethtool --set-mm eno0 pmac-enabled on tx-enabled on verify-enabled on

Preemptible packets should only be sent when the MAC Merge TX direction
becomes active (i.o.w. when the verification process succeeds, aka when
the link partner confirms it can process preemptible traffic). But the
tc qdisc with the preemptible traffic classes is offloaded completely
asynchronously w.r.t. the MM becoming active.

The ENETC manual does suggest that this should be handled in the driver:
"On startup, software should wait for the verification process to
complete (MMCSR[VSTS]=011) before initiating traffic".

Adding the necessary logic allows future selftests to uphold the claim
that an inactive or disabled MAC Merge layer should never send data
packets through the pMAC.

This change moves enetc_set_ptcfpr() from enetc.c to enetc_ethtool.c,
where its only caller is now - enetc_mm_commit_preemptible_tcs().
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The MMCSR register contains 2 fields with overlapping meaning:

- LPA (Local preemption active):
This read-only status bit indicates whether preemption is active for
this port. This bit will be set if preemption is both enabled and has
completed the verification process.
- TXSTS (Merge status):
This read-only status field provides the state of the MAC Merge sublayer
transmit status as defined in IEEE Std 802.3-2018 Clause 99.
00 Transmit preemption is inactive
01 Transmit preemption is active
10 Reserved
11 Reserved

However none of these 2 fields offer reliable reporting to software.

When connecting ENETC to a link partner which is not capable of Frame
Preemption, the expectation is that ENETC's verification should fail
(VSTS=4) and its MM TX direction should be inactive (LPA=0, TXSTS=00)
even though the MM TX is enabled (ME=1). But surprise, the LPA bit of
MMCSR stays set even if VSTS=4 and ME=1.

OTOH, the TXSTS field has the opposite problem. I cannot get its value
to change from 0, even when connecting to a link partner capable of
frame preemption, which does respond to its verification frames (ME=1
and VSTS=3, "SUCCEEDED").

The only option with such buggy hardware seems to be to reimplement the
formula for calculating tx-active in software, which is for tx-enabled
to be true, and for the verify-status to be either SUCCEEDED, or
DISABLED.

Without reliable tx-active reporting, we have no good indication when
to commit the preemptible traffic classes to hardware, which makes it
possible (but not desirable) to send preemptible traffic to a link
partner incapable of receiving it. However, currently we do not have the
logic to wait for TX to be active yet, so the impact is limited.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Current enetc_set_mm() is designed to set the priv->active_offloads bit
ENETC_F_QBU for enetc_mm_link_state_update() to act on, but if the link
is already up, it modifies the ENETC_MMCSR_ME ("Merge Enable") bit
directly.

The problem is that it only *sets* ENETC_MMCSR_ME if the link is up, it
doesn't *clear* it if needed. So subsequent enetc_get_mm() calls still
see tx-enabled as true, up until a link down event, which is when
enetc_mm_link_state_update() will get called.

This is not a functional issue as far as I can assess. It has only come
up because I'd like to uphold a simple API rule in core ethtool code:
the pMAC cannot be disabled if TX is going to be enabled. Currently,
the fact that TX remains enabled for longer than expected (after the
enetc_set_mm() call that disables it) is going to violate that rule,
which is how it was caught.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Refer to USB serial device or net device, there is a notice to
let end user know the status of device, like attached or
disconnected. Add attach/disconnect print for wwan device as
well.
Signed-off-by: Slark Xiao <slark_xiao@163.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/20230420023617.3919569-1-slark_xiao@163.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

__kfree_skb_defer() uses the old naming where "defer" meant
slab bulk free/alloc APIs. In the meantime we also made
__kfree_skb_defer() feed the per-NAPI skb cache, which
implies bulk APIs. So take away the 'defer' and add 'napi'.

While at it add a drop reason. This only matters on the
tx_action path, if the skb has a frag_list. But getting
rid of a SKB_DROP_REASON_NOT_SPECIFIED seems like a net
benefit so why not.
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20230420020005.815854-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Fix the following warning about risky iterator use:

drivers/net/ethernet/mellanox/mlx5/core/eq.c:1010 mlx5_comp_irq_get_affinity_mask() warn: iterator used outside loop: 'eq'
Acked-by: Saeed Mahameed <saeed@kernel.org>
Link: https://lore.kernel.org/r/20230420015802.815362-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Address a number of warnings flagged by
./scripts/kernel-doc -none include/net/flow_dissector.h

 include/net/flow_dissector.h:23: warning: Function parameter or member 'addr_type' not described in 'flow_dissector_key_control'
 include/net/flow_dissector.h:23: warning: Function parameter or member 'flags' not described in 'flow_dissector_key_control'
 include/net/flow_dissector.h:46: warning: Function parameter or member 'padding' not described in 'flow_dissector_key_basic'
 include/net/flow_dissector.h:145: warning: Function parameter or member 'tipckey' not described in 'flow_dissector_key_addrs'
 include/net/flow_dissector.h:157: warning: cannot understand function prototype: 'struct flow_dissector_key_arp '
 include/net/flow_dissector.h:171: warning: cannot understand function prototype: 'struct flow_dissector_key_ports '
 include/net/flow_dissector.h:203: warning: cannot understand function prototype: 'struct flow_dissector_key_icmp '

Also improve indentation on adjacent lines to those changed
to address the above.

No functional changes intended.
Signed-off-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230419-flow-dissector-kdoc-v1-1-1aa0cca1118b@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Jesper points out that we must prevent recycling into cache
after page_pool_destroy() is called, because page_pool_destroy()
is not synchronized with recycling (some pages may still be
outstanding when destroy() gets called).

I assumed this will not happen because NAPI can't be scheduled
if its page pool is being destroyed. But I missed the fact that
NAPI may get reused. For instance when user changes ring configuration
driver may allocate a new page pool, stop NAPI, swap, start NAPI,
and then destroy the old pool. The NAPI is running so old page
pool will think it can recycle to the cache, but the consumer
at that point is the destroy() path, not NAPI.

To avoid extra synchronization let the drivers do "unlinking"
during the "swap" stage while NAPI is indeed disabled.

Fixes: 8c48eea3 ("page_pool: allow caching from safely localized NAPI")
Reported-by: Jesper Dangaard Brouer <jbrouer@redhat.com>
Link: https://lore.kernel.org/all/e8df2654-6a5b-3c92-489d-2fe5e444135f@redhat.com/Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/r/20230419182006.719923-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The CONFIG_PHYLIB symbol is selected by a number of device drivers that
need PHY support, but it now has a dependency on CONFIG_LEDS_CLASS,
which may not be enabled, causing build failures.

Avoid the risk of missing and circular dependencies by guarding the
phylib LED support itself in another Kconfig symbol that can only be
enabled if the dependency is met.

This could be made a hidden symbol and always enabled when both CONFIG_OF
and CONFIG_LEDS_CLASS are reachable from the phylib, but there may be an
advantage in having users see this option when they have a misconfigured
kernel without built-in LED support.

Fixes: 01e5b728 ("net: phy: Add a binding for PHY LEDs")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230420084624.3005701-1-arnd@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Adjacent changes:

net/mptcp/protocol.h
  63740448 ("mptcp: fix accept vs worker race")
  2a6a870e ("mptcp: stops worker on unaccepted sockets at listener close")
  ddb1a072 ("mptcp: move first subflow allocation at mpc access time")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This partially reverts commit e161d4b6.

Turns out the channelmap variable is not actually read-only, it's modified
through the MCI_GPM_CLR_CHANNEL_BIT() macro further down in the function,
so making it read-only causes page faults when that code is hit.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217183
Link: https://lore.kernel.org/r/20230413214118.153781-1-toke@toke.dk
Fixes: e161d4b6 ("wifi: ath9k: Make arrays prof_prio and channelmap static const")
Cc: stable@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull Rust fixes from Miguel Ojeda:
 "Most of these are straightforward.

  The last one is more complex, but it only touches Rust + GCC builds
  which are for the moment best-effort.

   - Code: Missing 'extern "C"' fix.

   - Scripts: 'is_rust_module.sh' and 'generate_rust_analyzer.py' fixes.

   - A couple trivial fixes

   - Build: Rust + GCC build fix and 'grep' warning fix"

* tag 'rust-fixes-6.3' of https://github.com/Rust-for-Linux/linux:
  rust: allow to use INIT_STACK_ALL_ZERO
  rust: fix regexp in scripts/is_rust_module.sh
  rust: build: Fix grep warning
  scripts: generate_rust_analyzer: Handle sub-modules with no Makefile
  rust: kernel: Mark rust_fmt_argument as extern "C"
  rust: sort uml documentation arch support table
  rust: str: fix requierments->requirements typo

Pull networking fixes from Paolo Abeni:
 "Including fixes from netfilter and bpf.

  There are a few fixes for new code bugs, including the Mellanox one
  noted in the last networking pull. No known regressions outstanding.

  Current release - regressions:

   - sched: clear actions pointer in miss cookie init fail

   - mptcp: fix accept vs worker race

   - bpf: fix bpf_arch_text_poke() with new_addr == NULL on s390

   - eth: bnxt_en: fix a possible NULL pointer dereference in unload
     path

   - eth: veth: take into account peer device for
     NETDEV_XDP_ACT_NDO_XMIT xdp_features flag

  Current release - new code bugs:

   - eth: revert "net/mlx5: Enable management PF initialization"

  Previous releases - regressions:

   - netfilter: fix recent physdev match breakage

   - bpf: fix incorrect verifier pruning due to missing register
     precision taints

   - eth: virtio_net: fix overflow inside xdp_linearize_page()

   - eth: cxgb4: fix use after free bugs caused by circular dependency
     problem

   - eth: mlxsw: pci: fix possible crash during initialization

  Previous releases - always broken:

   - sched: sch_qfq: prevent slab-out-of-bounds in qfq_activate_agg

   - netfilter: validate catch-all set elements

   - bridge: don't notify FDB entries with "master dynamic"

   - eth: bonding: fix memory leak when changing bond type to ethernet

   - eth: i40e: fix accessing vsi->active_filters without holding lock

  Misc:

   - Mat is back as MPTCP co-maintainer"

* tag 'net-6.3-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (33 commits)
  net: bridge: switchdev: don't notify FDB entries with "master dynamic"
  Revert "net/mlx5: Enable management PF initialization"
  MAINTAINERS: Resume MPTCP co-maintainer role
  mailmap: add entries for Mat Martineau
  e1000e: Disable TSO on i219-LM card to increase speed
  bnxt_en: fix free-runnig PHC mode
  net: dsa: microchip: ksz8795: Correctly handle huge frame configuration
  bpf: Fix incorrect verifier pruning due to missing register precision taints
  hamradio: drop ISA_DMA_API dependency
  mlxsw: pci: Fix possible crash during initialization
  mptcp: fix accept vs worker race
  mptcp: stops worker on unaccepted sockets at listener close
  net: rpl: fix rpl header size calculation
  net: vmxnet3: Fix NULL pointer dereference in vmxnet3_rq_rx_complete()
  bonding: Fix memory leak when changing bond type to Ethernet
  veth: take into account peer device for NETDEV_XDP_ACT_NDO_XMIT xdp_features flag
  mlxfw: fix null-ptr-deref in mlxfw_mfa2_tlv_next()
  bnxt_en: Fix a possible NULL pointer dereference in unload path
  bnxt_en: Do not initialize PTP on older P3/P4 chips
  netfilter: nf_tables: tighten netlink attribute requirements for catch-all elements
  ...

When wx_alloc_page_pool() failed in wx_setup_rx_resources(), it doesn't
release DMA buffer. Add dma_free_coherent() in the error path to release
the DMA buffer.

Fixes: 850b9711 ("net: libwx: Allocate Rx and Tx resources")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230418065450.2268522-1-shaozhengchao@huawei.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

There is a structural problem in switchdev, where the flag bits in
struct switchdev_notifier_fdb_info (added_by_user, is_local etc) only
represent a simplified / denatured view of what's in struct
net_bridge_fdb_entry :: flags (BR_FDB_ADDED_BY_USER, BR_FDB_LOCAL etc).
Each time we want to pass more information about struct
net_bridge_fdb_entry :: flags to struct switchdev_notifier_fdb_info
(here, BR_FDB_STATIC), we find that FDB entries were already notified to
switchdev with no regard to this flag, and thus, switchdev drivers had
no indication whether the notified entries were static or not.

For example, this command:

ip link add br0 type bridge && ip link set swp0 master br0
bridge fdb add dev swp0 00:01:02:03:04:05 master dynamic

has never worked as intended with switchdev. It causes a struct
net_bridge_fdb_entry to be passed to br_switchdev_fdb_notify() which has
a single flag set: BR_FDB_ADDED_BY_USER.

This is further passed to the switchdev notifier chain, where interested
drivers have no choice but to assume this is a static (does not age) and
sticky (does not migrate) FDB entry. So currently, all drivers offload
it to hardware as such, as can be seen below ("offload" is set).

bridge fdb get 00:01:02:03:04:05 dev swp0 master
00:01:02:03:04:05 dev swp0 offload master br0

The software FDB entry expires $ageing_time centiseconds after the
kernel last sees a packet with this MAC SA, and the bridge notifies its
deletion as well, so it eventually disappears from hardware too.

This is a problem, because it is actually desirable to start offloading
"master dynamic" FDB entries correctly - they should expire $ageing_time
centiseconds after the *hardware* port last sees a packet with this
MAC SA - and this is how the current incorrect behavior was discovered.
With an offloaded data plane, it can be expected that software only sees
exception path packets, so an otherwise active dynamic FDB entry would
be aged out by software sooner than it should.

With the change in place, these FDB entries are no longer offloaded:

bridge fdb get 00:01:02:03:04:05 dev swp0 master
00:01:02:03:04:05 dev swp0 master br0

and this also constitutes a better way (assuming a backport to stable
kernels) for user space to determine whether the kernel has the
capability of doing something sane with these or not.

As opposed to "master dynamic" FDB entries, on the current behavior of
which no one currently depends on (which can be deduced from the lack of
kselftests), Ido Schimmel explains that entries with the "extern_learn"
flag (BR_FDB_ADDED_BY_EXT_LEARN) should still be notified to switchdev,
since the spectrum driver listens to them (and this is kind of okay,
because although they are treated identically to "static", they are
expected to not age, and to roam).

Fixes: 6b26b51b ("net: bridge: Add support for notifying devices about FDB add/del")
Link: https://lore.kernel.org/netdev/20230327115206.jk5q5l753aoelwus@skbuf/Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20230418155902.898627-1-vladimir.oltean@nxp.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

This reverts commit fe998a3c.

Paul reports that it causes a regression with IB on CX4
and FW 12.18.1000. In addition I think that the concept
of "management PF" is not fully accepted and requires
a discussion.

Fixes: fe998a3c ("net/mlx5: Enable management PF initialization")
Reported-by: Paul Moore <paul@paul-moore.com>
Link: https://lore.kernel.org/all/CAHC9VhQ7A4+msL38WpbOMYjAqLp0EtOjeLh4Dc6SQtD6OUvCQg@mail.gmail.com/
Link: https://lore.kernel.org/r/20230413222547.56901-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Chuck Lever says:

====================
Another crack at a handshake upcall mechanism

Here is v10 of a series to add generic support for transport layer
security handshake on behalf of kernel socket consumers (user space
consumers use a security library directly, of course). A summary of
the purpose of these patches is archived here:

https://lore.kernel.org/netdev/1DE06BB1-6BA9-4DB4-B2AA-07DE532963D6@oracle.com/

The first patch in the series applies to the top-level .gitignore
file to address the build warnings reported a few days ago. I intend
to submit that separately. I'd like you to consider taking the rest
of this series for v6.4.

The full patch set to support SunRPC with TLSv1.3 is available in
the topic-rpc-with-tls-upcall branch here, based on net-next/main:

https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git

This patch set includes support for in-transit confidentiality and
peer authentication for both the Linux NFS client and server.

A user space handshake agent for TLSv1.3 to go along with the kernel
patches is available in the "main" branch here:

https://github.com/oracle/ktls-utils
====================

Link: https://lore.kernel.org/r/168174169259.9520.1911007910797225963.stgit@91.116.238.104.host.secureserver.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

These verify the API contracts and help exercise lifetime rules for
consumer sockets and handshake_req structures.

One way to run these tests:

./tools/testing/kunit/kunit.py run --kunitconfig ./net/handshake/.kunitconfig
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

To enable kernel consumers of TLS to request a TLS handshake, add
support to net/handshake/ to request a handshake upcall.

This patch also acts as a template for adding handshake upcall
support for other kernel transport layer security providers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

When a kernel consumer needs a transport layer security session, it
first needs a handshake to negotiate and establish a session. This
negotiation can be done in user space via one of the several
existing library implementations, or it can be done in the kernel.

No in-kernel handshake implementations yet exist. In their absence,
we add a netlink service that can:

a. Notify a user space daemon that a handshake is needed.

b. Once notified, the daemon calls the kernel back via this
   netlink service to get the handshake parameters, including an
   open socket on which to establish the session.

c. Once the handshake is complete, the daemon reports the
   session status and other information via a second netlink
   operation. This operation marks that it is safe for the
   kernel to use the open socket and the security session
   established there.

The notification service uses a multicast group. Each handshake
mechanism (eg, tlshd) adopts its own group number so that the
handshake services are completely independent of one another. The
kernel can then tell via netlink_has_listeners() whether a handshake
service is active and prepared to handle a handshake request.

A new netlink operation, ACCEPT, acts like accept(2) in that it
instantiates a file descriptor in the user space daemon's fd table.
If this operation is successful, the reply carries the fd number,
which can be treated as an open and ready file descriptor.

While user space is performing the handshake, the kernel keeps its
muddy paws off the open socket. A second new netlink operation,
DONE, indicates that the user space daemon is finished with the
socket and it is safe for the kernel to use again. The operation
also indicates whether a session was established successfully.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Circumvent the .gitignore wildcard to avoid warnings about ignored
.kunitconfig files. As far as I can tell, the warnings are harmless
and these files are not actually ignored.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202304142337.jc4oUrov-lkp@intel.com/Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Merge tag 'ipsec-next-2023-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
ipsec-next 2023-04-19

1) Remove inner/outer modes from input/output path. These are
   not needed anymore. From Herbert Xu.

* tag 'ipsec-next-2023-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next:
  xfrm: Remove inner/outer modes from output path
  xfrm: Remove inner/outer modes from input path
====================

Link: https://lore.kernel.org/r/20230419075300.452227-1-steffen.klassert@secunet.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

A JSON pointer reference (the part after the "#") must start with a "/".
Conversely, references to the entire document must not have a trailing "/"
and should be just a "#". The existing jsonschema package allows these,
but coming changes make allowed "$ref" URIs stricter and throw errors on
these references.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230418150628.1528480-1-robh@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

At the beginning of the file micrel.c there is list of supported PHYs.
Extend this list with the following PHYs lan8841, lan8814 and lan8804,
as these PHYs were added but the list was not updated.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230418124713.2221451-1-horatiu.vultur@microchip.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Rather than casting clk_disable_unprepare to an incompatible function
type provide a trivial wrapper with the correct signature for the
use-case.

Reported by clang-16 with W=1:

 drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c:276:6: error: cast from 'void (*)(struct clk *)' to 'void (*)(void *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict]
                                        (void(*)(void *))clk_disable_unprepare,
                                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
No functional change intended.
Compile tested only.
Signed-off-by: Simon Horman <horms@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20230418-dwmac-meson8b-clk-cb-cast-v1-1-e892b670cbbb@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Daniel Borkmann says:

====================
bpf 2023-04-19

We've added 3 non-merge commits during the last 6 day(s) which contain
a total of 3 files changed, 34 insertions(+), 9 deletions(-).

The main changes are:

1) Fix a crash on s390's bpf_arch_text_poke() under a NULL new_addr,
   from Ilya Leoshkevich.

2) Fix a bug in BPF verifier's precision tracker, from Daniel Borkmann
   and Andrii Nakryiko.

3) Fix a regression in veth's xdp_features which led to a broken BPF CI
   selftest, from Lorenzo Bianconi.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Fix incorrect verifier pruning due to missing register precision taints
  veth: take into account peer device for NETDEV_XDP_ACT_NDO_XMIT xdp_features flag
  s390/bpf: Fix bpf_arch_text_poke() with new_addr == NULL
====================

Link: https://lore.kernel.org/r/20230419195847.27060-1-daniel@iogearbox.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

I'm returning to the MPTCP maintainer role I held for most of the
subsytem's history. This time I'm using my kernel.org email address.
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/mptcp/af85e467-8d0a-4eba-b5f8-e2f2c5d24984@tessares.net/Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20230418231318.115331-1-martineau@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Map Mat's old corporate addresses to his kernel.org one.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/20230418-upstream-net-20230418-mailmap-mat-v1-1-13ca5dc83037@tessares.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Tony Nguyen says:

====================
Intel Wired LAN Driver Updates 2023-04-17 (i40e)

This series contains updates to i40e only.

Alex moves setting of active filters to occur under lock and checks/takes
error path in rebuild if re-initializing the misc interrupt vector
failed.

* '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue:
  i40e: fix i40e_setup_misc_vector() error handling
  i40e: fix accessing vsi->active_filters without holding lock
====================
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230417205245.1030733-1-anthony.l.nguyen@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Merge tag 'mm-hotfixes-stable-2023-04-19-16-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "22 hotfixes.

  19 are cc:stable and the remainder address issues which were
  introduced during this merge cycle, or aren't considered suitable for
  -stable backporting.

  19 are for MM and the remainder are for other subsystems"

* tag 'mm-hotfixes-stable-2023-04-19-16-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
  nilfs2: initialize unused bytes in segment summary blocks
  mm: page_alloc: skip regions with hugetlbfs pages when allocating 1G pages
  mm/mmap: regression fix for unmapped_area{_topdown}
  maple_tree: fix mas_empty_area() search
  maple_tree: make maple state reusable after mas_empty_area_rev()
  mm: kmsan: handle alloc failures in kmsan_ioremap_page_range()
  mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush()
  tools/Makefile: do missed s/vm/mm/
  mm: fix memory leak on mm_init error handling
  mm/page_alloc: fix potential deadlock on zonelist_update_seq seqlock
  kernel/sys.c: fix and improve control flow in __sys_setres[ug]id()
  Revert "userfaultfd: don't fail on unrecognized features"
  writeback, cgroup: fix null-ptr-deref write in bdi_split_work_to_wbs
  maple_tree: fix a potential memory leak, OOB access, or other unpredictable bug
  tools/mm/page_owner_sort.c: fix TGID output when cull=tg is used
  mailmap: update jtoppins' entry to reference correct email
  mm/mempolicy: fix use-after-free of VMA iterator
  mm/huge_memory.c: warn with pr_warn_ratelimited instead of VM_WARN_ON_ONCE_FOLIO
  mm/mprotect: fix do_mprotect_pkey() return on error
  mm/khugepaged: check again on anon uffd-wp during isolation
  ...

While using i219-LM card currently it was only possible to achieve
about 60% of maximum speed due to regression introduced in Linux 5.8.
This was caused by TSO not being disabled by default despite commit
f2980103 ("e1000e: Disable TSO for buffer overrun workaround").
Fix that by disabling TSO during driver probe.

Fixes: f2980103 ("e1000e: Disable TSO for buffer overrun workaround")
Signed-off-by: Sebastian Basierski <sebastianx.basierski@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230417205345.1030801-1-anthony.l.nguyen@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The patch in fixes changed the way real-time mode is chosen for PHC on
the NIC. Apparently there is one more use case of the check outside of
ptp part of the driver which was not converted to the new macro and is
making a lot of noise in free-running mode.

Fixes: 131db499 ("bnxt_en: reset PHC frequency in free-running mode")
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://lore.kernel.org/r/20230418202511.1544735-1-vadfed@meta.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

There are two variants of the MT7531 switch IC which got different
features (and pins) regarding port 5:
 * MT7531AE: SGMII/1000Base-X/2500Base-X SerDes PCS
 * MT7531BE: RGMII

Moving the creation of the SerDes PCS from mt753x_setup to mt7530_probe
with commit 6de28522 ("net: dsa: mt7530: move SGMII PCS creation
to mt7530_probe function") works fine for MT7531AE which got two
instances of mtk-pcs-lynxi, however, MT7531BE requires mt7531_pll_setup
to setup clocks before the single PCS on port 6 (usually used as CPU
port) starts to work and hence the PCS creation failed on MT7531BE.

Fix this by introducing a pointer to mt7531_create_sgmii function in
struct mt7530_priv and call it again at the end of mt753x_setup like it
was before commit 6de28522 ("net: dsa: mt7530: move SGMII PCS
creation to mt7530_probe function").

Fixes: 6de28522 ("net: dsa: mt7530: move SGMII PCS creation to mt7530_probe function")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Acked-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Link: https://lore.kernel.org/r/ZDvlLhhqheobUvOK@makrotopia.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Pull spi fix from Mark Brown:
 "A small fix in the error handling for the rockchip driver, ensuring we
  don't leak clock enables if we fail to request the interrupt for the
  device"

* tag 'spi-fix-v6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: spi-rockchip: Fix missing unwind goto in rockchip_sfc_probe()

Merge tag 'regulator-fix-v6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fixes from Mark Brown:
 "A few driver specific fixes, one build coverage issue and a couple of
  'someone typed in the wrong number' style errors in describing devices
  to the subsystem"

* tag 'regulator-fix-v6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: sm5703: Fix missing n_voltages for fixed regulators
  regulator: fan53555: Fix wrong TCS_SLEW_MASK
  regulator: fan53555: Explicitly include bits header

Because of the logic in place, SW_HUGE_PACKET can never be set.
(If the first condition is true, then the 2nd one is also true, but is not
executed)

Change the logic and update each bit individually.

Fixes: 29d1e85f ("net: dsa: microchip: ksz8: add MTU configuration support")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/43107d9e8b5b8b05f0cbd4e1f47a2bb88c8747b2.1681755535.git.christophe.jaillet@wanadoo.frSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Commit c519fe9a ("bnxt: add dma mapping attributes") added
DMA_ATTR_WEAK_ORDERING to DMA attrs on bnxt. It has since spread
to a few more drivers (possibly as a copy'n'paste).

DMA_ATTR_WEAK_ORDERING only seems to matter on Sparc and PowerPC/cell,
the rarity of these platforms is likely why we never bothered adding
the attribute in the page pool, even though it should be safe to add.

To make the page pool migration in drivers which set this flag less
of a risk (of regressing the precious sparc database workloads or
whatever needed this) let's add DMA_ATTR_WEAK_ORDERING on all
page pool DMA mappings.

We could make this a driver opt-in but frankly I don't think it's
worth complicating the API. I can't think of a reason why device
accesses to packet memory would have to be ordered.
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/r/20230417152805.331865-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

With CONFIG_INIT_STACK_ALL_ZERO enabled, bindgen passes
-ftrivial-auto-var-init=zero to clang, that triggers the following
error:

 error: '-ftrivial-auto-var-init=zero' hasn't been enabled; enable it at your own peril for benchmarking purpose only with '-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang'

However, this additional option that is currently required by clang is
deprecated since clang-16 and going to be removed in the future,
likely with clang-18.

So, make sure bindgen is using this extra option if the major version of
the libclang used by bindgen is < 16.

In this way we can enable CONFIG_INIT_STACK_ALL_ZERO with CONFIG_RUST
without triggering any build error.

Link: https://github.com/llvm/llvm-project/issues/44842
Link: https://github.com/llvm/llvm-project/blob/llvmorg-16.0.0-rc2/clang/docs/ReleaseNotes.rst#deprecated-compiler-flagsSigned-off-by: Andrea Righi <andrea.righi@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[Changed to < 16, added link and reworded]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

nm can use "R" or "r" to show read-only data sections, but
scripts/is_rust_module.sh can only recognize "r", so with some versions
of binutils it can fail to detect if a module is a Rust module or not.

Right now we're using this script only to determine if we need to skip
BTF generation (that is disabled globally if CONFIG_RUST is enabled),
but it's still nice to fix this script to do the proper job.

Moreover, with this patch applied I can also relax the constraint of
"RUST depends on !DEBUG_INFO_BTF" and build a kernel with Rust and BTF
enabled at the same time (of course BTF generation is still skipped for
Rust modules).

[ Miguel: The actual reason is likely to be a change on the Rust
  compiler between 1.61.0 and 1.62.0:

    echo '#[used] static S: () = ();' |
        rustup run 1.61.0 rustc --emit=obj --crate-type=lib - &&
        nm rust_out.o

    echo '#[used] static S: () = ();' |
        rustup run 1.62.0 rustc --emit=obj --crate-type=lib - &&
        nm rust_out.o

  Gives:

    0000000000000000 r _ZN8rust_out1S17h48027ce0da975467E
    0000000000000000 R _ZN8rust_out1S17h58e1f3d9c0e97cefE

  See https://godbolt.org/z/KE6jneoo4. ]
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Eric Curtin <ecurtin@redhat.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Juan Jose et al reported an issue found via fuzzing where the verifier's
pruning logic prematurely marks a program path as safe.

Consider the following program:

   0: (b7) r6 = 1024
   1: (b7) r7 = 0
   2: (b7) r8 = 0
   3: (b7) r9 = -2147483648
   4: (97) r6 %= 1025
   5: (05) goto pc+0
   6: (bd) if r6 <= r9 goto pc+2
   7: (97) r6 %= 1
   8: (b7) r9 = 0
   9: (bd) if r6 <= r9 goto pc+1
  10: (b7) r6 = 0
  11: (b7) r0 = 0
  12: (63) *(u32 *)(r10 -4) = r0
  13: (18) r4 = 0xffff888103693400 // map_ptr(ks=4,vs=48)
  15: (bf) r1 = r4
  16: (bf) r2 = r10
  17: (07) r2 += -4
  18: (85) call bpf_map_lookup_elem#1
  19: (55) if r0 != 0x0 goto pc+1
  20: (95) exit
  21: (77) r6 >>= 10
  22: (27) r6 *= 8192
  23: (bf) r1 = r0
  24: (0f) r0 += r6
  25: (79) r3 = *(u64 *)(r0 +0)
  26: (7b) *(u64 *)(r1 +0) = r3
  27: (95) exit

The verifier treats this as safe, leading to oob read/write access due
to an incorrect verifier conclusion:

  func#0 @0
  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (b7) r6 = 1024                     ; R6_w=1024
  1: (b7) r7 = 0                        ; R7_w=0
  2: (b7) r8 = 0                        ; R8_w=0
  3: (b7) r9 = -2147483648              ; R9_w=-2147483648
  4: (97) r6 %= 1025                    ; R6_w=scalar()
  5: (05) goto pc+0
  6: (bd) if r6 <= r9 goto pc+2         ; R6_w=scalar(umin=18446744071562067969,var_off=(0xffffffff00000000; 0xffffffff)) R9_w=-2147483648
  7: (97) r6 %= 1                       ; R6_w=scalar()
  8: (b7) r9 = 0                        ; R9=0
  9: (bd) if r6 <= r9 goto pc+1         ; R6=scalar(umin=1) R9=0
  10: (b7) r6 = 0                       ; R6_w=0
  11: (b7) r0 = 0                       ; R0_w=0
  12: (63) *(u32 *)(r10 -4) = r0
  last_idx 12 first_idx 9
  regs=1 stack=0 before 11: (b7) r0 = 0
  13: R0_w=0 R10=fp0 fp-8=0000????
  13: (18) r4 = 0xffff8ad3886c2a00      ; R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  15: (bf) r1 = r4                      ; R1_w=map_ptr(off=0,ks=4,vs=48,imm=0) R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  16: (bf) r2 = r10                     ; R2_w=fp0 R10=fp0
  17: (07) r2 += -4                     ; R2_w=fp-4
  18: (85) call bpf_map_lookup_elem#1   ; R0=map_value_or_null(id=1,off=0,ks=4,vs=48,imm=0)
  19: (55) if r0 != 0x0 goto pc+1       ; R0=0
  20: (95) exit

  from 19 to 21: R0=map_value(off=0,ks=4,vs=48,imm=0) R6=0 R7=0 R8=0 R9=0 R10=fp0 fp-8=mmmm????
  21: (77) r6 >>= 10                    ; R6_w=0
  22: (27) r6 *= 8192                   ; R6_w=0
  23: (bf) r1 = r0                      ; R0=map_value(off=0,ks=4,vs=48,imm=0) R1_w=map_value(off=0,ks=4,vs=48,imm=0)
  24: (0f) r0 += r6
  last_idx 24 first_idx 19
  regs=40 stack=0 before 23: (bf) r1 = r0
  regs=40 stack=0 before 22: (27) r6 *= 8192
  regs=40 stack=0 before 21: (77) r6 >>= 10
  regs=40 stack=0 before 19: (55) if r0 != 0x0 goto pc+1
  parent didn't have regs=40 stack=0 marks: R0_rw=map_value_or_null(id=1,off=0,ks=4,vs=48,imm=0) R6_rw=P0 R7=0 R8=0 R9=0 R10=fp0 fp-8=mmmm????
  last_idx 18 first_idx 9
  regs=40 stack=0 before 18: (85) call bpf_map_lookup_elem#1
  regs=40 stack=0 before 17: (07) r2 += -4
  regs=40 stack=0 before 16: (bf) r2 = r10
  regs=40 stack=0 before 15: (bf) r1 = r4
  regs=40 stack=0 before 13: (18) r4 = 0xffff8ad3886c2a00
  regs=40 stack=0 before 12: (63) *(u32 *)(r10 -4) = r0
  regs=40 stack=0 before 11: (b7) r0 = 0
  regs=40 stack=0 before 10: (b7) r6 = 0
  25: (79) r3 = *(u64 *)(r0 +0)         ; R0_w=map_value(off=0,ks=4,vs=48,imm=0) R3_w=scalar()
  26: (7b) *(u64 *)(r1 +0) = r3         ; R1_w=map_value(off=0,ks=4,vs=48,imm=0) R3_w=scalar()
  27: (95) exit

  from 9 to 11: R1=ctx(off=0,imm=0) R6=0 R7=0 R8=0 R9=0 R10=fp0
  11: (b7) r0 = 0                       ; R0_w=0
  12: (63) *(u32 *)(r10 -4) = r0
  last_idx 12 first_idx 11
  regs=1 stack=0 before 11: (b7) r0 = 0
  13: R0_w=0 R10=fp0 fp-8=0000????
  13: (18) r4 = 0xffff8ad3886c2a00      ; R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  15: (bf) r1 = r4                      ; R1_w=map_ptr(off=0,ks=4,vs=48,imm=0) R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  16: (bf) r2 = r10                     ; R2_w=fp0 R10=fp0
  17: (07) r2 += -4                     ; R2_w=fp-4
  18: (85) call bpf_map_lookup_elem#1
  frame 0: propagating r6
  last_idx 19 first_idx 11
  regs=40 stack=0 before 18: (85) call bpf_map_lookup_elem#1
  regs=40 stack=0 before 17: (07) r2 += -4
  regs=40 stack=0 before 16: (bf) r2 = r10
  regs=40 stack=0 before 15: (bf) r1 = r4
  regs=40 stack=0 before 13: (18) r4 = 0xffff8ad3886c2a00
  regs=40 stack=0 before 12: (63) *(u32 *)(r10 -4) = r0
  regs=40 stack=0 before 11: (b7) r0 = 0
  parent didn't have regs=40 stack=0 marks: R1=ctx(off=0,imm=0) R6_r=P0 R7=0 R8=0 R9=0 R10=fp0
  last_idx 9 first_idx 9
  regs=40 stack=0 before 9: (bd) if r6 <= r9 goto pc+1
  parent didn't have regs=40 stack=0 marks: R1=ctx(off=0,imm=0) R6_rw=Pscalar() R7_w=0 R8_w=0 R9_rw=0 R10=fp0
  last_idx 8 first_idx 0
  regs=40 stack=0 before 8: (b7) r9 = 0
  regs=40 stack=0 before 7: (97) r6 %= 1
  regs=40 stack=0 before 6: (bd) if r6 <= r9 goto pc+2
  regs=40 stack=0 before 5: (05) goto pc+0
  regs=40 stack=0 before 4: (97) r6 %= 1025
  regs=40 stack=0 before 3: (b7) r9 = -2147483648
  regs=40 stack=0 before 2: (b7) r8 = 0
  regs=40 stack=0 before 1: (b7) r7 = 0
  regs=40 stack=0 before 0: (b7) r6 = 1024
  19: safe
  frame 0: propagating r6
  last_idx 9 first_idx 0
  regs=40 stack=0 before 6: (bd) if r6 <= r9 goto pc+2
  regs=40 stack=0 before 5: (05) goto pc+0
  regs=40 stack=0 before 4: (97) r6 %= 1025
  regs=40 stack=0 before 3: (b7) r9 = -2147483648
  regs=40 stack=0 before 2: (b7) r8 = 0
  regs=40 stack=0 before 1: (b7) r7 = 0
  regs=40 stack=0 before 0: (b7) r6 = 1024

  from 6 to 9: safe
  verification time 110 usec
  stack depth 4
  processed 36 insns (limit 1000000) max_states_per_insn 0 total_states 3 peak_states 3 mark_read 2

The verifier considers this program as safe by mistakenly pruning unsafe
code paths. In the above func#0, code lines 0-10 are of interest. In line
0-3 registers r6 to r9 are initialized with known scalar values. In line 4
the register r6 is reset to an unknown scalar given the verifier does not
track modulo operations. Due to this, the verifier can also not determine
precisely which branches in line 6 and 9 are taken, therefore it needs to
explore them both.

As can be seen, the verifier starts with exploring the false/fall-through
paths first. The 'from 19 to 21' path has both r6=0 and r9=0 and the pointer
arithmetic on r0 += r6 is therefore considered safe. Given the arithmetic,
r6 is correctly marked for precision tracking where backtracking kicks in
where it walks back the current path all the way where r6 was set to 0 in
the fall-through branch.

Next, the pruning logics pops the path 'from 9 to 11' from the stack. Also
here, the state of the registers is the same, that is, r6=0 and r9=0, so
that at line 19 the path can be pruned as it is considered safe. It is
interesting to note that the conditional in line 9 turned r6 into a more
precise state, that is, in the fall-through path at the beginning of line
10, it is R6=scalar(umin=1), and in the branch-taken path (which is analyzed
here) at the beginning of line 11, r6 turned into a known const r6=0 as
r9=0 prior to that and therefore (unsigned) r6 <= 0 concludes that r6 must
be 0 (**):

  [...]                                 ; R6_w=scalar()
  9: (bd) if r6 <= r9 goto pc+1         ; R6=scalar(umin=1) R9=0
  [...]

  from 9 to 11: R1=ctx(off=0,imm=0) R6=0 R7=0 R8=0 R9=0 R10=fp0
  [...]

The next path is 'from 6 to 9'. The verifier considers the old and current
state equivalent, and therefore prunes the search incorrectly. Looking into
the two states which are being compared by the pruning logic at line 9, the
old state consists of R6_rwD=Pscalar() R9_rwD=0 R10=fp0 and the new state
consists of R1=ctx(off=0,imm=0) R6_w=scalar(umax=18446744071562067968)
R7_w=0 R8_w=0 R9_w=-2147483648 R10=fp0. While r6 had the reg->precise flag
correctly set in the old state, r9 did not. Both r6'es are considered as
equivalent given the old one is a superset of the current, more precise one,
however, r9's actual values (0 vs 0x80000000) mismatch. Given the old r9
did not have reg->precise flag set, the verifier does not consider the
register as contributing to the precision state of r6, and therefore it
considered both r9 states as equivalent. However, for this specific pruned
path (which is also the actual path taken at runtime), register r6 will be
0x400 and r9 0x80000000 when reaching line 21, thus oob-accessing the map.

The purpose of precision tracking is to initially mark registers (including
spilled ones) as imprecise to help verifier's pruning logic finding equivalent
states it can then prune if they don't contribute to the program's safety
aspects. For example, if registers are used for pointer arithmetic or to pass
constant length to a helper, then the verifier sets reg->precise flag and
backtracks the BPF program instruction sequence and chain of verifier states
to ensure that the given register or stack slot including their dependencies
are marked as precisely tracked scalar. This also includes any other registers
and slots that contribute to a tracked state of given registers/stack slot.
This backtracking relies on recorded jmp_history and is able to traverse
entire chain of parent states. This process ends only when all the necessary
registers/slots and their transitive dependencies are marked as precise.

The backtrack_insn() is called from the current instruction up to the first
instruction, and its purpose is to compute a bitmask of registers and stack
slots that need precision tracking in the parent's verifier state. For example,
if a current instruction is r6 = r7, then r6 needs precision after this
instruction and r7 needs precision before this instruction, that is, in the
parent state. Hence for the latter r7 is marked and r6 unmarked.

For the class of jmp/jmp32 instructions, backtrack_insn() today only looks
at call and exit instructions and for all other conditionals the masks
remain as-is. However, in the given situation register r6 has a dependency
on r9 (as described above in **), so also that one needs to be marked for
precision tracking. In other words, if an imprecise register influences a
precise one, then the imprecise register should also be marked precise.
Meaning, in the parent state both dest and src register need to be tracked
for precision and therefore the marking must be more conservative by setting
reg->precise flag for both. The precision propagation needs to cover both
for the conditional: if the src reg was marked but not the dst reg and vice
versa.

After the fix the program is correctly rejected:

  func#0 @0
  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (b7) r6 = 1024                     ; R6_w=1024
  1: (b7) r7 = 0                        ; R7_w=0
  2: (b7) r8 = 0                        ; R8_w=0
  3: (b7) r9 = -2147483648              ; R9_w=-2147483648
  4: (97) r6 %= 1025                    ; R6_w=scalar()
  5: (05) goto pc+0
  6: (bd) if r6 <= r9 goto pc+2         ; R6_w=scalar(umin=18446744071562067969,var_off=(0xffffffff80000000; 0x7fffffff),u32_min=-2147483648) R9_w=-2147483648
  7: (97) r6 %= 1                       ; R6_w=scalar()
  8: (b7) r9 = 0                        ; R9=0
  9: (bd) if r6 <= r9 goto pc+1         ; R6=scalar(umin=1) R9=0
  10: (b7) r6 = 0                       ; R6_w=0
  11: (b7) r0 = 0                       ; R0_w=0
  12: (63) *(u32 *)(r10 -4) = r0
  last_idx 12 first_idx 9
  regs=1 stack=0 before 11: (b7) r0 = 0
  13: R0_w=0 R10=fp0 fp-8=0000????
  13: (18) r4 = 0xffff9290dc5bfe00      ; R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  15: (bf) r1 = r4                      ; R1_w=map_ptr(off=0,ks=4,vs=48,imm=0) R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  16: (bf) r2 = r10                     ; R2_w=fp0 R10=fp0
  17: (07) r2 += -4                     ; R2_w=fp-4
  18: (85) call bpf_map_lookup_elem#1   ; R0=map_value_or_null(id=1,off=0,ks=4,vs=48,imm=0)
  19: (55) if r0 != 0x0 goto pc+1       ; R0=0
  20: (95) exit

  from 19 to 21: R0=map_value(off=0,ks=4,vs=48,imm=0) R6=0 R7=0 R8=0 R9=0 R10=fp0 fp-8=mmmm????
  21: (77) r6 >>= 10                    ; R6_w=0
  22: (27) r6 *= 8192                   ; R6_w=0
  23: (bf) r1 = r0                      ; R0=map_value(off=0,ks=4,vs=48,imm=0) R1_w=map_value(off=0,ks=4,vs=48,imm=0)
  24: (0f) r0 += r6
  last_idx 24 first_idx 19
  regs=40 stack=0 before 23: (bf) r1 = r0
  regs=40 stack=0 before 22: (27) r6 *= 8192
  regs=40 stack=0 before 21: (77) r6 >>= 10
  regs=40 stack=0 before 19: (55) if r0 != 0x0 goto pc+1
  parent didn't have regs=40 stack=0 marks: R0_rw=map_value_or_null(id=1,off=0,ks=4,vs=48,imm=0) R6_rw=P0 R7=0 R8=0 R9=0 R10=fp0 fp-8=mmmm????
  last_idx 18 first_idx 9
  regs=40 stack=0 before 18: (85) call bpf_map_lookup_elem#1
  regs=40 stack=0 before 17: (07) r2 += -4
  regs=40 stack=0 before 16: (bf) r2 = r10
  regs=40 stack=0 before 15: (bf) r1 = r4
  regs=40 stack=0 before 13: (18) r4 = 0xffff9290dc5bfe00
  regs=40 stack=0 before 12: (63) *(u32 *)(r10 -4) = r0
  regs=40 stack=0 before 11: (b7) r0 = 0
  regs=40 stack=0 before 10: (b7) r6 = 0
  25: (79) r3 = *(u64 *)(r0 +0)         ; R0_w=map_value(off=0,ks=4,vs=48,imm=0) R3_w=scalar()
  26: (7b) *(u64 *)(r1 +0) = r3         ; R1_w=map_value(off=0,ks=4,vs=48,imm=0) R3_w=scalar()
  27: (95) exit

  from 9 to 11: R1=ctx(off=0,imm=0) R6=0 R7=0 R8=0 R9=0 R10=fp0
  11: (b7) r0 = 0                       ; R0_w=0
  12: (63) *(u32 *)(r10 -4) = r0
  last_idx 12 first_idx 11
  regs=1 stack=0 before 11: (b7) r0 = 0
  13: R0_w=0 R10=fp0 fp-8=0000????
  13: (18) r4 = 0xffff9290dc5bfe00      ; R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  15: (bf) r1 = r4                      ; R1_w=map_ptr(off=0,ks=4,vs=48,imm=0) R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  16: (bf) r2 = r10                     ; R2_w=fp0 R10=fp0
  17: (07) r2 += -4                     ; R2_w=fp-4
  18: (85) call bpf_map_lookup_elem#1
  frame 0: propagating r6
  last_idx 19 first_idx 11
  regs=40 stack=0 before 18: (85) call bpf_map_lookup_elem#1
  regs=40 stack=0 before 17: (07) r2 += -4
  regs=40 stack=0 before 16: (bf) r2 = r10
  regs=40 stack=0 before 15: (bf) r1 = r4
  regs=40 stack=0 before 13: (18) r4 = 0xffff9290dc5bfe00
  regs=40 stack=0 before 12: (63) *(u32 *)(r10 -4) = r0
  regs=40 stack=0 before 11: (b7) r0 = 0
  parent didn't have regs=40 stack=0 marks: R1=ctx(off=0,imm=0) R6_r=P0 R7=0 R8=0 R9=0 R10=fp0
  last_idx 9 first_idx 9
  regs=40 stack=0 before 9: (bd) if r6 <= r9 goto pc+1
  parent didn't have regs=240 stack=0 marks: R1=ctx(off=0,imm=0) R6_rw=Pscalar() R7_w=0 R8_w=0 R9_rw=P0 R10=fp0
  last_idx 8 first_idx 0
  regs=240 stack=0 before 8: (b7) r9 = 0
  regs=40 stack=0 before 7: (97) r6 %= 1
  regs=40 stack=0 before 6: (bd) if r6 <= r9 goto pc+2
  regs=240 stack=0 before 5: (05) goto pc+0
  regs=240 stack=0 before 4: (97) r6 %= 1025
  regs=240 stack=0 before 3: (b7) r9 = -2147483648
  regs=40 stack=0 before 2: (b7) r8 = 0
  regs=40 stack=0 before 1: (b7) r7 = 0
  regs=40 stack=0 before 0: (b7) r6 = 1024
  19: safe

  from 6 to 9: R1=ctx(off=0,imm=0) R6_w=scalar(umax=18446744071562067968) R7_w=0 R8_w=0 R9_w=-2147483648 R10=fp0
  9: (bd) if r6 <= r9 goto pc+1
  last_idx 9 first_idx 0
  regs=40 stack=0 before 6: (bd) if r6 <= r9 goto pc+2
  regs=240 stack=0 before 5: (05) goto pc+0
  regs=240 stack=0 before 4: (97) r6 %= 1025
  regs=240 stack=0 before 3: (b7) r9 = -2147483648
  regs=40 stack=0 before 2: (b7) r8 = 0
  regs=40 stack=0 before 1: (b7) r7 = 0
  regs=40 stack=0 before 0: (b7) r6 = 1024
  last_idx 9 first_idx 0
  regs=200 stack=0 before 6: (bd) if r6 <= r9 goto pc+2
  regs=240 stack=0 before 5: (05) goto pc+0
  regs=240 stack=0 before 4: (97) r6 %= 1025
  regs=240 stack=0 before 3: (b7) r9 = -2147483648
  regs=40 stack=0 before 2: (b7) r8 = 0
  regs=40 stack=0 before 1: (b7) r7 = 0
  regs=40 stack=0 before 0: (b7) r6 = 1024
  11: R6=scalar(umax=18446744071562067968) R9=-2147483648
  11: (b7) r0 = 0                       ; R0_w=0
  12: (63) *(u32 *)(r10 -4) = r0
  last_idx 12 first_idx 11
  regs=1 stack=0 before 11: (b7) r0 = 0
  13: R0_w=0 R10=fp0 fp-8=0000????
  13: (18) r4 = 0xffff9290dc5bfe00      ; R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  15: (bf) r1 = r4                      ; R1_w=map_ptr(off=0,ks=4,vs=48,imm=0) R4_w=map_ptr(off=0,ks=4,vs=48,imm=0)
  16: (bf) r2 = r10                     ; R2_w=fp0 R10=fp0
  17: (07) r2 += -4                     ; R2_w=fp-4
  18: (85) call bpf_map_lookup_elem#1   ; R0_w=map_value_or_null(id=3,off=0,ks=4,vs=48,imm=0)
  19: (55) if r0 != 0x0 goto pc+1       ; R0_w=0
  20: (95) exit

  from 19 to 21: R0=map_value(off=0,ks=4,vs=48,imm=0) R6=scalar(umax=18446744071562067968) R7=0 R8=0 R9=-2147483648 R10=fp0 fp-8=mmmm????
  21: (77) r6 >>= 10                    ; R6_w=scalar(umax=18014398507384832,var_off=(0x0; 0x3fffffffffffff))
  22: (27) r6 *= 8192                   ; R6_w=scalar(smax=9223372036854767616,umax=18446744073709543424,var_off=(0x0; 0xffffffffffffe000),s32_max=2147475456,u32_max=-8192)
  23: (bf) r1 = r0                      ; R0=map_value(off=0,ks=4,vs=48,imm=0) R1_w=map_value(off=0,ks=4,vs=48,imm=0)
  24: (0f) r0 += r6
  last_idx 24 first_idx 21
  regs=40 stack=0 before 23: (bf) r1 = r0
  regs=40 stack=0 before 22: (27) r6 *= 8192
  regs=40 stack=0 before 21: (77) r6 >>= 10
  parent didn't have regs=40 stack=0 marks: R0_rw=map_value(off=0,ks=4,vs=48,imm=0) R6_r=Pscalar(umax=18446744071562067968) R7=0 R8=0 R9=-2147483648 R10=fp0 fp-8=mmmm????
  last_idx 19 first_idx 11
  regs=40 stack=0 before 19: (55) if r0 != 0x0 goto pc+1
  regs=40 stack=0 before 18: (85) call bpf_map_lookup_elem#1
  regs=40 stack=0 before 17: (07) r2 += -4
  regs=40 stack=0 before 16: (bf) r2 = r10
  regs=40 stack=0 before 15: (bf) r1 = r4
  regs=40 stack=0 before 13: (18) r4 = 0xffff9290dc5bfe00
  regs=40 stack=0 before 12: (63) *(u32 *)(r10 -4) = r0
  regs=40 stack=0 before 11: (b7) r0 = 0
  parent didn't have regs=40 stack=0 marks: R1=ctx(off=0,imm=0) R6_rw=Pscalar(umax=18446744071562067968) R7_w=0 R8_w=0 R9_w=-2147483648 R10=fp0
  last_idx 9 first_idx 0
  regs=40 stack=0 before 9: (bd) if r6 <= r9 goto pc+1
  regs=240 stack=0 before 6: (bd) if r6 <= r9 goto pc+2
  regs=240 stack=0 before 5: (05) goto pc+0
  regs=240 stack=0 before 4: (97) r6 %= 1025
  regs=240 stack=0 before 3: (b7) r9 = -2147483648
  regs=40 stack=0 before 2: (b7) r8 = 0
  regs=40 stack=0 before 1: (b7) r7 = 0
  regs=40 stack=0 before 0: (b7) r6 = 1024
  math between map_value pointer and register with unbounded min value is not allowed
  verification time 886 usec
  stack depth 4
  processed 49 insns (limit 1000000) max_states_per_insn 1 total_states 5 peak_states 5 mark_read 2

Fixes: b5dc0163 ("bpf: precise scalar_value tracking")
Reported-by: Juan Jose Lopez Jaimez <jjlopezjaimez@google.com>
Reported-by: Meador Inge <meadori@google.com>
Reported-by: Simon Scannell <simonscannell@google.com>
Reported-by: Nenad Stojanovski <thenenadx@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Reviewed-by: Juan Jose Lopez Jaimez <jjlopezjaimez@google.com>
Reviewed-by: Meador Inge <meadori@google.com>
Reviewed-by: Simon Scannell <simonscannell@google.com>