This is a defense-in-depth measure in response to bugs like
4d6fa57b ("macsec: avoid heap overflow in skb_to_sgvec"). There's
not only a potential overflow of sglist items, but also a stack overflow
potential, so we fix this by limiting the amount of recursion this function
is allowed to do. Not actually providing a bounded base case is a future
disaster that we can easily avoid here.

As a small matter of house keeping, we take this opportunity to move the
documentation comment over the actual function the documentation is for.

While this could be implemented by using an explicit stack of skbuffs,
when implementing this, the function complexity increased considerably,
and I don't think such complexity and bloat is actually worth it. So,
instead I built this and tested it on x86, x86_64, ARM, ARM64, and MIPS,
and measured the stack usage there. I also reverted the recent MIPS
changes that give it a separate IRQ stack, so that I could experience
some worst-case situations. I found that limiting it to 24 layers deep
yielded a good stack usage with room for safety, as well as being much
deeper than any driver actually ever creates.
Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Howells <dhowells@redhat.com>
Cc: Sabrina Dubroca <sd@queasysnail.net>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge branch 'bpf-Add-BPF-support-to-all-perf_event'

Alexei Starovoitov says:

====================
bpf: Add BPF support to all perf_event

v3->v4: one more tweak to reject unsupported events at map
update time as Peter suggested

v2->v3: more refactoring to address Peter's feedback.
Now all perf_events are attachable and readable

v1->v2: address Peter's feedback. Refactor patch 1 to allow attaching
bpf programs to all event types and reading counters from all of them as well
patch 2 - more tests
patch 3 - address Dave's feedback and document bpf_perf_event_read()
and bpf_perf_event_output() properly
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit updates documentation of the bpf_perf_event_output and
bpf_perf_event_read helpers to match their implementation.
Signed-off-by: NTeng Qin <qinteng@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

$ trace_event

tests attaching BPF program to HW_CPU_CYCLES, SW_CPU_CLOCK, HW_CACHE_L1D and other events.
It runs 'dd' in the background while bpf program collects user and kernel
stack trace on counter overflow.
User space expects to see sys_read and sys_write in the kernel stack.

$ tracex6

tests reading of various perf counters from BPF program.

Both tests were refactored to increase coverage and be more accurate.
Signed-off-by: NTeng Qin <qinteng@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow BPF_PROG_TYPE_PERF_EVENT program types to attach to all
perf_event types, including HW_CACHE, RAW, and dynamic pmu events.
Only tracepoint/kprobe events are treated differently which require
BPF_PROG_TYPE_TRACEPOINT/BPF_PROG_TYPE_KPROBE program types accordingly.

Also add support for reading all event counters using
bpf_perf_event_read() helper.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The command
  # arp -s 62.2.0.1 a:b:c:d:e:f dev eth2
adds an entry like the following (listed by "arp -an")
  ? (62.2.0.1) at 0a:0b:0c:0d:0e:0f [ether] PERM on eth2
but the symmetric deletion command
  # arp -i eth2 -d 62.2.0.1
does not remove the PERM entry from the table, and instead leaves behind
  ? (62.2.0.1) at <incomplete> on eth2

The reason is that there is a refcnt of 1 for the arp_tbl itself
(neigh_alloc starts off the entry with a refcnt of 1), thus
the neigh_release() call from arp_invalidate() will (at best) just
decrement the ref to 1, but will never actually free it from the
table.

To fix this, we need to do something like neigh_forced_gc: if
the refcnt is 1 (i.e., on the table's ref), remove the entry from
the table and free it. This patch refactors and shares common code
between neigh_forced_gc and the newly added neigh_remove_one.

A similar issue exists for IPv6 Neighbor Cache entries, and is fixed
in a similar manner by this patch.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Reviewed-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most of the PHYs supported by the SMSC driver have a counter of symbol
errors. This is 16 bit wide and wraps around when it reaches its
maximum value.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-By: NWoojung Huh <Woojung.Huh@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Andrew Lunn says:

====================
dsa: Fixes for mv88e6161

Testing a board with an mv88e6161 turned up two issues. The PHYs were
not found, because the wrong method to access them was used. The
statistics did not work, because the wrong snapshot method was used
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The mv88e6161 was using the wrong method to perform statistics
snapshot.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Access to the internal PHYs of the 6161 and 6123 go through global 2
SMI registers. Fix the ops structure.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Vivien Didelot says:

====================
net: dsa: mv88e6xxx: move registers macros

This patchset brings no functional changes.

It is the first step of a cleanup renaming the chip header file and
moving the Register definitions _as is_ in their proper header files.

A following patchset will prefix them with the appropriate model
(MV88E6XXX_ or e.g. MV88E6390_) to respect an implicit namespace and
easily identify model subtleties in registers layout, as correctly done
in the newly added serdes.h header.
====================
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the GLOBAL2_* macros where they belong, in the related global2.h
header.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the GLOBAL_* macros where they belong, in the related global1.h
header. Include it in global2.c which uses GLOBAL_STATUS_IRQ_DEVICE.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the PORT_* macros where they belong, in the related port.h header.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the PHY_* macros where they belong, in the related phy.h header.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The mv88e6xxx.h is meant to contains the chip structures and data.
Rename it to chip.h, as for other source/header pairs of the driver.

At the same time, ensure that relative header inclusions are separated
by a newline and sorted alphabetically.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Florian Fainelli says:

====================
net: dsa: Cleanups before multi-CPU port

This patch series does a bunch of cleanups before we start adding support
for multiple CPU ports.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There was no reason for duplicating the code that initializes
ds->enabled_port_mask in both dsa_parse_ports_dn() and
dsa_parse_ports(), instead move this to dsa_ds_parse() which is early
enough before ops->setup() has run.

While at it, we can now make dsa_is_cpu_port() check ds->cpu_port_mask
which is a step towards being multi-CPU port capable.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have all the information we need in dsa_port, so use it instead of
repeating the same arguments over and over again.
Suggested-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We do not need to have a reference to a dsa_switch, instead we should
pass a reference to a CPU dsa_port, change that. This is a preliminary
change to better support multiple CPU ports.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The proc_remove call is dead code as it occurs after a return and
hence can never be called. Remove it.

Detected by CoverityScan, CID#1437743 ("Logically dead code")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DCCP uses dccp_write_space() for sk->sk_write_space method.

Unfortunately a passive connection (as provided by accept())
is using the generic sk_stream_write_space() function.

Lets simply inherit sk->sk_write_space from the parent
instead of forcing the generic one.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

functions m88e1510_get_temp_critical, m88e1510_set_temp_critical and
m88e1510_get_temp_alarm can be made static as they not need to be
in global scope.

Cleans up sparse warnings:
 "symbol 'm88e1510_get_temp_alarm' was not declared. Should it be static?"
 "symbol 'm88e1510_get_temp_critical' was not declared. Should it be
  static?"
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of rewriting write/readq, use linux/io-64-nonatomic-lo-hi.h which
already have them.
Signed-off-by: NCorentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Save a bit of code by using the kernel extension.

$ size net/core/net-procfs.o*
   text	   data	    bss	    dec	    hex	filename
   3701	    120	      0	   3821	    eed	net/core/net-procfs.o.new
   3764	    120	      0	   3884	    f2c	net/core/net-procfs.o.old
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If any errors are encountered while walking the device tree structure of
the MDIO bus for children, the code may silently continue, silently
exit, or throw an error and exit.  This make it difficult for device
tree writers to know there is an error.  Also, it makes any error in a
child entry of the MDIO bus be fatal for all entries.  Instead, we
should provide verbose errors describing the error and then attempt to
continue if it all possible.  Also, use of_mdio_parse_addr()
Signed-off-by: NJon Mason <jon.mason@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Or Gerlitz says:

====================
net: add support for dissection and matching on ip tos and ttl

The 1st two patches enable matching/classifying on ip tos and ttl by
the flow dissector and flower. The other two patches offload matching
on tcp flags and ip tos in mlx5.

The mlx5 patches touch single file/function and not interfere with
other inflight mlx5 submissions.

V2:  repost as asked by Dave.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable offloading of TC matching on ipv4 tos or ipv6 traffic-class.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable offloading of TC matching on tcp flags.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Benefit from the support of ip header fields dissection and
allow users to set rules matching on ipv4 tos and ttl or
ipv6 traffic-class and hoplimit.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for dissection of ip tos and ttl and ipv6 traffic-class
and hoplimit. Both are dissected into the same struct.

Uses similar call to ip dissection function as with tcp, arp and others.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__pskb_trim_head() does not need to reset skb tail pointer.

Also change the comments, __pskb_pull_head() does not exist.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently loading a cgroup skb eBPF program require a CAP_SYS_ADMIN
capability while attaching the program to a cgroup only requires the
user have CAP_NET_ADMIN privilege. We can escape the capability
check when load the program just like socket filter program to make
the capability requirement consistent.

Change since v1:
Change the code style in order to be compliant with checkpatch.pl
preference
Signed-off-by: NChenbo Feng <fengc@google.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows cgroup eBPF program to classify packet based on their
protocol or other detail information. Currently program need
CAP_NET_ADMIN privilege to attach a cgroup eBPF program, and A
process with CAP_NET_ADMIN can already see all packets on the system,
for example, by creating an iptables rules that causes the packet to
be passed to userspace via NFLOG.
Signed-off-by: NChenbo Feng <fengc@google.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

use of_mdio_parse_addr() in place of an OF read of reg and a bounds
check (which is litterally the exact same thing that
of_mdio_parse_addr() does)
Signed-off-by: NJon Mason <jon.mason@broadcom.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently when a data packet is retransmitted, we do not compute an
RTT sample for congestion control due to Kern's check. Therefore the
congestion control that uses RTT signals may not receive any update
during loss recovery which could last many round trips. For example,
BBR and Vegas may not be able to update its min RTT estimation if the
network path has shortened until it recovers from losses. This patch
mitigates that by using TCP timestamp options for RTT measurement
for congestion control. Note that we already use timestamps for
RTT estimation.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NSatanand Burla <satananda.burla@cavium.com>
Signed-off-by: NDerek Chickles <derek.chickles@cavium.com>
Signed-off-by: NFelix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On HyperV, the VF interface can be offered by a host at any time.
Mark the VF interface as hotplug, to make sure it will be brought up
automatically when it is registered.
Signed-off-by: NSimon Xiao <sixiao@microsoft.com>
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On HyperV, the VF interface can be offered by a host at any time.
Mark the VF interface as hotplug, to make sure it will be brought up
automatically when it is registered.
Signed-off-by: NSimon Xiao <sixiao@microsoft.com>
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Set initialization state variable to (reflect interrupt initialization) at
correct time (immediately after having configured interrupts).  This fixes
problem of inconsistent IRQ allocation in case of [obscure] failure when
negotiating with PF driver during init.

Clean-up of interrupt enablement during initialization & avoid potential
race condition with chip-specific code (i.e. perform interrupt control in
main driver module).  Added explanatory comments regarding interrupt
enablement.
Signed-off-by: NRick Farrington <ricardo.farrington@cavium.com>
Signed-off-by: NSatanand Burla <satananda.burla@cavium.com>
Signed-off-by: NFelix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>