If SACK is not enabled and the first cumulative ACK after the RTO
retransmission covers more than the retransmitted skb, a spurious
FRTO undo will trigger (assuming FRTO is enabled for that RTO).
The reason is that any non-retransmitted segment acknowledged will
set FLAG_ORIG_SACK_ACKED in tcp_clean_rtx_queue even if there is
no indication that it would have been delivered for real (the
scoreboard is not kept with TCPCB_SACKED_ACKED bits in the non-SACK
case so the check for that bit won't help like it does with SACK).
Having FLAG_ORIG_SACK_ACKED set results in the spurious FRTO undo
in tcp_process_loss.

We need to use more strict condition for non-SACK case and check
that none of the cumulatively ACKed segments were retransmitted
to prove that progress is due to original transmissions. Only then
keep FLAG_ORIG_SACK_ACKED set, allowing FRTO undo to proceed in
non-SACK case.

(FLAG_ORIG_SACK_ACKED is planned to be renamed to FLAG_ORIG_PROGRESS
to better indicate its purpose but to keep this change minimal, it
will be done in another patch).

Besides burstiness and congestion control violations, this problem
can result in RTO loop: When the loss recovery is prematurely
undoed, only new data will be transmitted (if available) and
the next retransmission can occur only after a new RTO which in case
of multiple losses (that are not for consecutive packets) requires
one RTO per loss to recover.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Tested-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Daniel Borkmann says:

====================
pull-request: bpf 2018-07-01

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) A bpf_fib_lookup() helper fix to change the API before freeze to
   return an encoding of the FIB lookup result and return the nexthop
   device index in the params struct (instead of device index as return
   code that we had before), from David.

2) Various BPF JIT fixes to address syzkaller fallout, that is, do not
   reject progs when set_memory_*() fails since it could still be RO.
   Also arm32 JIT was not using bpf_jit_binary_lock_ro() API which was
   an issue, and a memory leak in s390 JIT found during review, from
   Daniel.

3) Multiple fixes for sockmap/hash to address most of the syzkaller
   triggered bugs. Usage with IPv6 was crashing, a GPF in bpf_tcp_close(),
   a missing sock_map_release() routine to hook up to callbacks, and a
   fix for an omitted bucket lock in sock_close(), from John.

4) Two bpftool fixes to remove duplicated error message on program load,
   and another one to close the libbpf object after program load. One
   additional fix for nfp driver's BPF offload to avoid stopping offload
   completely if replace of program failed, from Jakub.

5) Couple of BPF selftest fixes that bail out in some of the test
   scripts if the user does not have the right privileges, from Jeffrin.

6) Fixes in test_bpf for s390 when CONFIG_BPF_JIT_ALWAYS_ON is set
   where we need to set the flag that some of the test cases are expected
   to fail, from Kleber.

7) Fix to detangle BPF_LIRC_MODE2 dependency from CONFIG_CGROUP_BPF
   since it has no relation to it and lirc2 users often have configs
   without cgroups enabled and thus would not be able to use it, from Sean.

8) Fix a selftest failure in sockmap by removing a useless setrlimit()
   call that would set a too low limit where at the same time we are
   already including bpf_rlimit.h that does the job, from Yonghong.

9) Fix BPF selftest config with missing missing NET_SCHED, from Anders.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

John Fastabend says:

====================
This addresses two syzbot issues that lead to identifying (by Eric and
Wei) a class of bugs where we don't correctly check for IPv4/v6
sockets and their associated state. The second issue was a locking
omission in sockhash.

The first patch addresses IPv6 socks and fixing an error where
sockhash would overwrite the prot pointer with IPv4 prot. To fix
this build similar solution to TLS ULP. Although we continue to
allow socks in all states not just ESTABLISH in this patch set
because as Martin points out there should be no issue with this
on the sockmap ULP because we don't use the ctx in this code. Once
multiple ULPs coexist we may need to revisit this. However we
can do this in *next trees.

The other issue syzbot found that the tcp_close() handler missed
locking the hash bucket lock which could result in corrupting the
sockhash bucket list if delete and close ran at the same time.
And also the smap_list_remove() routine was not working correctly
at all. This was not caught in my testing because in general my
tests (to date at least lets add some more robust selftest in
bpf-next) do things in the "expected" order, create map, add socks,
delete socks, then tear down maps. The tests we have that do the
ops out of this order where only working on single maps not multi-
maps so we never saw the issue. Thanks syzbot. The fix is to
restructure the tcp_close() lock handling. And fix the obvious
bug in smap_list_remove().

Finally, during review I noticed the release handler was omitted
from the upstream code (patch 4) due to an incorrect merge conflict
fix when I ported the code to latest bpf-next before submitting.
This would leave references to the map around if the user never
closes the map.

v3: rework patches, dropping ESTABLISH check and adding rcu
    annotation along with the smap_list_remove fix

v4: missed one more case where maps was being accessed without
    the sk_callback_lock, spoted by Martin as well.

v5: changed to use a specific lock for maps and reduced callback
    lock so that it is only used to gaurd sk callbacks. I think
    this makes the logic a bit cleaner and avoids confusion
    ovoer what each lock is doing.

Also big thanks to Martin for thorough review he caught at least
one case where I missed a rcu_call().
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add map_release_uref pointer to hashmap ops. This was dropped when
original sockhash code was ported into bpf-next before initial
commit.

Fixes: 81110384 ("bpf: sockmap, add hash map support")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

First the sk_callback_lock() was being used to protect both the
sock callback hooks and the psock->maps list. This got overly
convoluted after the addition of sockhash (in sockmap it made
some sense because masp and callbacks were tightly coupled) so
lets split out a specific lock for maps and only use the callback
lock for its intended purpose. This fixes a couple cases where
we missed using maps lock when it was in fact needed. Also this
makes it easier to follow the code because now we can put the
locking closer to the actual code its serializing.

Next, in sock_hash_delete_elem() the pattern was as follows,

  sock_hash_delete_elem()
     [...]
     spin_lock(bucket_lock)
     l = lookup_elem_raw()
     if (l)
        hlist_del_rcu()
        write_lock(sk_callback_lock)
         .... destroy psock ...
        write_unlock(sk_callback_lock)
     spin_unlock(bucket_lock)

The ordering is necessary because we only know the {p}sock after
dereferencing the hash table which we can't do unless we have the
bucket lock held. Once we have the bucket lock and the psock element
it is deleted from the hashmap to ensure any other path doing a lookup
will fail. Finally, the refcnt is decremented and if zero the psock
is destroyed.

In parallel with the above (or free'ing the map) a tcp close event
may trigger tcp_close(). Which at the moment omits the bucket lock
altogether (oops!) where the flow looks like this,

  bpf_tcp_close()
     [...]
     write_lock(sk_callback_lock)
     for each psock->maps // list of maps this sock is part of
         hlist_del_rcu(ref_hash_node);
         .... destroy psock ...
     write_unlock(sk_callback_lock)

Obviously, and demonstrated by syzbot, this is broken because
we can have multiple threads deleting entries via hlist_del_rcu().

To fix this we might be tempted to wrap the hlist operation in a
bucket lock but that would create a lock inversion problem. In
summary to follow locking rules the psocks maps list needs the
sk_callback_lock (after this patch maps_lock) but we need the bucket
lock to do the hlist_del_rcu.

To resolve the lock inversion problem pop the head of the maps list
repeatedly and remove the reference until no more are left. If a
delete happens in parallel from the BPF API that is OK as well because
it will do a similar action, lookup the lock in the map/hash, delete
it from the map/hash, and dec the refcnt. We check for this case
before doing a destroy on the psock to ensure we don't have two
threads tearing down a psock. The new logic is as follows,

  bpf_tcp_close()
  e = psock_map_pop(psock->maps) // done with map lock
  bucket_lock() // lock hash list bucket
  l = lookup_elem_raw(head, hash, key, key_size);
  if (l) {
     //only get here if elmnt was not already removed
     hlist_del_rcu()
     ... destroy psock...
  }
  bucket_unlock()

And finally for all the above to work add missing locking around  map
operations per above. Then add RCU annotations and use
rcu_dereference/rcu_assign_pointer to manage values relying on RCU so
that the object is not free'd from sock_hash_free() while it is being
referenced in bpf_tcp_close().

Reported-by: syzbot+0ce137753c78f7b6acc1@syzkaller.appspotmail.com
Fixes: 81110384 ("bpf: sockmap, add hash map support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

If a hashmap is free'd with open socks it removes the reference to
the hash entry from the psock. If that is the last reference to the
psock then it will also be free'd by the reference counting logic.
However the current logic that removes the hash reference from the
list of references is broken. In smap_list_remove() we first check
if the sockmap entry matches and then check if the hashmap entry
matches. But, the sockmap entry sill always match because its NULL in
this case which causes the first entry to be removed from the list.
If this is always the "right" entry (because the user adds/removes
entries in order) then everything is OK but otherwise a subsequent
bpf_tcp_close() may reference a free'd object.

To fix this create two list handlers one for sockmap and one for
sockhash.

Reported-by: syzbot+0ce137753c78f7b6acc1@syzkaller.appspotmail.com
Fixes: 81110384 ("bpf: sockmap, add hash map support")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

This fixes a crash where we assign tcp_prot to IPv6 sockets instead
of tcpv6_prot.

Previously we overwrote the sk->prot field with tcp_prot even in the
AF_INET6 case. This patch ensures the correct tcp_prot and tcpv6_prot
are used.

Tested with 'netserver -6' and 'netperf -H [IPv6]' as well as
'netperf -H [IPv4]'. The ESTABLISHED check resolves the previously
crashing case here.

Fixes: 174a79ff ("bpf: sockmap with sk redirect support")
Reported-by: syzbot+5c063698bdbfac19f363@syzkaller.appspotmail.com
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

After commit f9d4b0c1 ("fib_rules: move common handling of newrule
delrule msgs into fib_nl2rule"), rule_exists got replaced by rule_find
for existing rule lookup in both the add and del paths. While this
is good for the delete path, it solves a few problems but opens up
a few invalid key matches in the add path.

$ip -4 rule add table main tos 10 fwmark 1
$ip -4 rule add table main tos 10
RTNETLINK answers: File exists

The problem here is rule_find does not check if the key masks in
the new and old rule are the same and hence ends up matching a more
secific rule. Rule key masks cannot be easily compared today without
an elaborate if-else block. Its best to introduce key masks for easier
and accurate rule comparison in the future. Until then, due to fear of
regressions this patch re-introduces older loose rule_exists during add.
Also fixes both rule_exists and rule_find to cover missing attributes.

Fixes: f9d4b0c1 ("fib_rules: move common handling of newrule delrule msgs into fib_nl2rule")
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When doing device hotplug the sub channel must be async to avoid
deadlock issues because device is discovered in softirq context.

When doing changes to MTU and number of channels, the setup
must be synchronous to avoid races such as when MTU and device
settings are done in a single ip command.
Reported-by: Thomas Walker <Thomas.Walker@twosigma.com>
Fixes: 8195b139 ("hv_netvsc: fix deadlock on hotplug")
Fixes: 732e4985 ("netvsc: fix race on sub channel creation")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As noticed by Eric, we need to switch to the helper
dev_change_tx_queue_len() for SIOCSIFTXQLEN call path too,
otheriwse still miss dev_qdisc_change_tx_queue_len().

Fixes: 6a643ddb ("net: introduce helper dev_change_tx_queue_len()")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

pool can be indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

drivers/atm/zatm.c:1491 zatm_ioctl() warn: potential spectre issue
'zatm_dev->pool_info' (local cap)

Fix this by sanitizing pool before using it to index
zatm_dev->pool_info

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: fixes 2018-06-29

please apply a few qeth fixes for -net and your 4.17 stable queue.

Patches 1-3 fix several issues wrt to MAC address management that were
introduced during the 4.17 cycle.
Patch 4 tackles a long-standing issue with busy multi-connection workloads
on devices in af_iucv mode.
Patch 5 makes sure to re-enable all active HW offloads, after a card was
previously set offline and thus lost its HW context.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

commit e830baa9 ("qeth: restore device features after recovery") and
commit ce344356 ("s390/qeth: rely on kernel for feature recovery")
made sure that the HW functions for device features get re-programmed
after recovery.

But we missed that the same handling is also required when a card is
first set offline (destroying all HW context), and then online again.
Fix this by moving the re-enable action out of the recovery-only path.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If qeth_qdio_output_handler() detects that a transmit requires async
completion, it replaces the pending buffer's metadata object
(qeth_qdio_out_buffer) so that this queue buffer can be re-used while
the data is pending completion.

Later when the CQ indicates async completion of such a metadata object,
qeth_qdio_cq_handler() tries to free any data associated with this
object (since HW has now completed the transfer). By calling
qeth_clear_output_buffer(), it erronously operates on the queue buffer
that _previously_ belonged to this transfer ... but which has been
potentially re-used several times by now.
This results in double-free's of the buffer's data, and failing
transmits as the buffer descriptor is scrubbed in mid-air.

The correct way of handling this situation is to
1. scrub the queue buffer when it is prepared for re-use, and
2. later obtain the data addresses from the async-completion notifier
   (ie. the AOB), instead of the queue buffer.

All this only affects qeth devices used for af_iucv HiperTransport.

Fixes: 0da9581d ("qeth: exploit asynchronous delivery of storage blocks")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

*ether_addr*_64bits functions have been introduced to optimize
performance critical paths, which access 6-byte ethernet address as u64
value to get "nice" assembly. A harmless hack works nicely on ethernet
addresses shoved into a structure or a larger buffer, until busted by
Kasan on smth like plain (u8 *)[6].

qeth_l2_set_mac_address calls qeth_l2_remove_mac passing
u8 old_addr[ETH_ALEN] as an argument.

Adding/removing macs for an ethernet adapter is not that performance
critical. Moreover is_multicast_ether_addr_64bits itself on s390 is not
faster than is_multicast_ether_addr:

is_multicast_ether_addr(%r2) -> %r2
llc	%r2,0(%r2)
risbg	%r2,%r2,63,191,0

is_multicast_ether_addr_64bits(%r2) -> %r2
llgc	%r2,0(%r2)
risbg	%r2,%r2,63,191,0

So, let's just use is_multicast_ether_addr instead of
is_multicast_ether_addr_64bits.

Fixes: bcacfcbc ("s390/qeth: fix MAC address update sequence")
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When qeth_l2_set_mac_address() finds the card in a non-reachable state,
it merely copies the new MAC address into dev->dev_addr so that
__qeth_l2_set_online() can later register it with the HW.

But __qeth_l2_set_online() may very well be running concurrently, so we
can't trust the card state without appropriate locking:
If the online sequence is past the point where it registers
dev->dev_addr (but not yet in SOFTSETUP state), any address change needs
to be properly programmed into the HW. Otherwise the netdevice ends up
with a different MAC address than what's set in the HW, and inbound
traffic is not forwarded as expected.

This is most likely to occur for OSD in LPAR, where
commit 21b1702a ("s390/qeth: improve fallback to random MAC address")
now triggers eg. systemd to immediately change the MAC when the netdevice
is registered with a NET_ADDR_RANDOM address.

Fixes: bcacfcbc ("s390/qeth: fix MAC address update sequence")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit b7493e91.

On its own, querying RDEV for a MAC address works fine. But when upgrading
from a qeth that previously queried DDEV on a z/VM NIC (ie. any kernel with
commit ec61bd2f), the RDEV query now returns a _different_ MAC address
than the DDEV query.

If the NIC is configured with MACPROTECT, z/VM apparently requires us to
use the MAC that was initially returned (on DDEV) and registered. So after
upgrading to a kernel that uses RDEV, the SETVMAC registration cmd for the
new MAC address fails and we end up with a non-operabel interface.

To avoid regressions on upgrade, switch back to using DDEV for the MAC
address query. The downgrade path (first RDEV, later DDEV) is fine, in this
case both queries return the same MAC address.

Fixes: b7493e91 ("s390/qeth: use Read device to query hypervisor for MAC")
Reported-by: Michal Kubecek <mkubecek@suse.com>
Tested-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The __alx_open function can be called from ndo_open, which is called
under RTNL, or from alx_resume, which isn't. Since commit d768319c,
we're calling the netif_set_real_num_{tx,rx}_queues functions, which
need to be called under RTNL.

This is similar to commit 0c2cc02e ("igb: Move the calls to set the
Tx and Rx queues into igb_open").

Fixes: d768319c ("alx: enable multiple tx queues")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes: fc7a6c28 ("sfc: use a semaphore to lock farch filters too")
Suggested-by: Joseph Korty <joe.korty@concurrent-rt.com>
Signed-off-by: Bert Kenward <bkenward@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix a bug where INT_STAT1 was written twice and
INT_STAT2 was ignored when disabling interrupts.

Fixes: b753a9fa ("net: phy: DP83TC811: Introduce support for the DP83TC811 phy")
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sowmini reported that a recent commit broke prefix routes for linklocal
addresses. The newly added modify_prefix_route is attempting to add a
new prefix route when the ifp priority does not match the route metric
however the check needs to account for the default priority. In addition,
the route add fails because the route already exists, and then the delete
removes the one that exists. Flip the order to do the delete first.

Fixes: 8308f3ff ("net/ipv6: Add support for specifying metric of connected routes")
Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

alloc_skb_with_frags uses __GFP_NORETRY for non-sleeping allocations
which is just a noop and a little bit confusing.

__GFP_NORETRY was added by ed98df33 ("net: use __GFP_NORETRY for
high order allocations") to prevent from the OOM killer. Yet this was
not enough because fb05e7a8 ("net: don't wait for order-3 page
allocation") didn't want an excessive reclaim for non-costly orders
so it made it completely NOWAIT while it preserved __GFP_NORETRY in
place which is now redundant.

Drop the pointless __GFP_NORETRY because this function is used as
copy&paste source for other places.
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Madalin Bucur says:

====================
DPAA fixes

A couple of fixes for the DPAA drivers, addressing an issue
with short UDP or TCP frames (with padding) that were marked
as having a wrong checksum and dropped by the FMan hardware
and a problem with the buffer used for the scatter-gather
table being too small as per the hardware requirements.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The DPAA HW requires that at least 256 bytes from the start of the
first scatter-gather table entry are allocated and accessible. The
hardware reads the maximum size the table can have in one access,
thus requiring that the allocation and mapping to be done for the
maximum size of 256B even if there is a smaller number of entries
in the table.
Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The FMan hardware parser needs to be configured to remove the
short frame padding from the checksum calculation, otherwise
short UDP and TCP frames are likely to be marked as having a
bad checksum.
Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Driver performs the internal reload when it receives tx-timeout event from
the OS. Internal reload might fail in some scenarios e.g., fatal HW issues.
In such cases OS still see the link, which would result in undesirable
functionalities such as re-generation of tx-timeouts.
The patch addresses this issue by indicating the link-down to OS when
tx-timeout is detected, and keeping the link in down state till the
internal reload is successful.

Please consider applying it to 'net' branch.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Static checkers complain that id_tbl->table points to longs and 4 bytes
is smaller than sizeof(long).  But the since other side is dividing by
32 instead of sizeof(long), that means the current code works fine.

Anyway, it's more conventional to use the BITS_TO_LONGS() macro when
we're allocating a bitmap.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The code assumes that there is 4 bytes in a pointer and it doesn't
allocate enough memory.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fast Open key could be stored in different endian based on the CPU.
Previously hosts in different endianness in a server farm using
the same key config (sysctl value) would produce different cookies.
This patch fixes it by always storing it as little endian to keep
same API for LE hosts.
Reported-by: Daniele Iamartino <danielei@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Daniel Borkmann says:

====================
This set contains three fixes that are mostly JIT and set_memory_*()
related. The third in the series in particular fixes the syzkaller
bugs that were still pending; aside from local reproduction & testing,
also 'syz test' wasn't able to trigger them anymore. I've tested this
series on x86_64, arm64 and s390x, and kbuild bot wasn't yelling either
for the rest. For details, please see patches as usual, thanks!
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Partially undo commit 9facc336 ("bpf: reject any prog that failed
read-only lock") since it caused a regression, that is, syzkaller was
able to manage to cause a panic via fault injection deep in set_memory_ro()
path by letting an allocation fail: In x86's __change_page_attr_set_clr()
it was able to change the attributes of the primary mapping but not in
the alias mapping via cpa_process_alias(), so the second, inner call
to the __change_page_attr() via __change_page_attr_set_clr() had to split
a larger page and failed in the alloc_pages() with the artifically triggered
allocation error which is then propagated down to the call site.

Thus, for set_memory_ro() this means that it returned with an error, but
from debugging a probe_kernel_write() revealed EFAULT on that memory since
the primary mapping succeeded to get changed. Therefore the subsequent
hdr->locked = 0 reset triggered the panic as it was performed on read-only
memory, so call-site assumptions were infact wrong to assume that it would
either succeed /or/ not succeed at all since there's no such rollback in
set_memory_*() calls from partial change of mappings, in other words, we're
left in a state that is "half done". A later undo via set_memory_rw() is
succeeding though due to matching permissions on that part (aka due to the
try_preserve_large_page() succeeding). While reproducing locally with
explicitly triggering this error, the initial splitting only happens on
rare occasions and in real world it would additionally need oom conditions,
but that said, it could partially fail. Therefore, it is definitely wrong
to bail out on set_memory_ro() error and reject the program with the
set_memory_*() semantics we have today. Shouldn't have gone the extra mile
since no other user in tree today infact checks for any set_memory_*()
errors, e.g. neither module_enable_ro() / module_disable_ro() for module
RO/NX handling which is mostly default these days nor kprobes core with
alloc_insn_page() / free_insn_page() as examples that could be invoked long
after bootup and original 314beb9b ("x86: bpf_jit_comp: secure bpf jit
against spraying attacks") did neither when it got first introduced to BPF
so "improving" with bailing out was clearly not right when set_memory_*()
cannot handle it today.

Kees suggested that if set_memory_*() can fail, we should annotate it with
__must_check, and all callers need to deal with it gracefully given those
set_memory_*() markings aren't "advisory", but they're expected to actually
do what they say. This might be an option worth to move forward in future
but would at the same time require that set_memory_*() calls from supporting
archs are guaranteed to be "atomic" in that they provide rollback if part
of the range fails, once that happened, the transition from RW -> RO could
be made more robust that way, while subsequent RO -> RW transition /must/
continue guaranteeing to always succeed the undo part.

Reported-by: syzbot+a4eb8c7766952a1ca872@syzkaller.appspotmail.com
Reported-by: syzbot+d866d1925855328eac3b@syzkaller.appspotmail.com
Fixes: 9facc336 ("bpf: reject any prog that failed read-only lock")
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

If we would ever fail in the bpf_jit_prog() pass that writes the
actual insns to the image after we got header via bpf_jit_binary_alloc()
then we also need to make sure to free it through bpf_jit_binary_free()
again when bailing out. Given we had prior bpf_jit_prog() passes to
initially probe for clobbered registers, program size and to fill in
addrs arrray for jump targets, this is more of a theoretical one,
but at least make sure this doesn't break with future changes.

Fixes: 05462310 ("s390/bpf: Add s390x eBPF JIT compiler backend")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Any eBPF JIT that where its underlying arch supports ARCH_HAS_SET_MEMORY
would need to use bpf_jit_binary_{un,}lock_ro() pair instead of the
set_memory_{ro,rw}() pair directly as otherwise changes to the former
might break. arm32's eBPF conversion missed to change it, so fix this
up here.

Fixes: 39c13c20 ("arm: eBPF JIT compiler")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Merge tag 'mac80211-for-davem-2018-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Just three fixes:
 * fix HT operation in mesh mode
 * disable preemption in control frame TX
 * check nla_parse_nested() return values
   where missing (two places)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently the kernel accounts the memory for network traffic through
mem_cgroup_[un]charge_skmem() interface. However the memory accounted
only includes the truesize of sk_buff which does not include the size of
sock objects. In our production environment, with opt-out kmem
accounting, the sock kmem caches (TCP[v6], UDP[v6], RAW[v6], UNIX) are
among the top most charged kmem caches and consume a significant amount
of memory which can not be left as system overhead. So, this patch
converts the kmem caches of all sock objects to SLAB_ACCOUNT.
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

At the very least we should check the return value if
nla_parse_nested() is called with a non-NULL policy.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Commit 9757235f, "nl80211: correct checks for
NL80211_MESHCONF_HT_OPMODE value") relaxed the range for the HT
operation field in meshconf, while also adding checks requiring
the non-greenfield and non-ht-sta bits to be set in certain
circumstances.  The latter bit is actually reserved for mesh BSSes
according to Table 9-168 in 802.11-2016, so in fact it should not
be set.

wpa_supplicant sets these bits because the mesh and AP code share
the same implementation, but authsae does not.  As a result, some
meshconf updates from authsae which set only the NONHT_MIXED
protection bits were being rejected.

In order to avoid breaking userspace by changing the rules again,
simply accept the values with or without the bits set, and mask
off the reserved bit to match the spec.

While in here, update the 802.11-2012 reference to 802.11-2016.

Fixes: 9757235f ("nl80211: correct checks for NL80211_MESHCONF_HT_OPMODE value")
Cc: Masashi Honma <masashi.honma@gmail.com>
Signed-off-by: Bob Copeland <bobcopeland@fb.com>
Reviewed-by: Masashi Honma <masashi.honma@gmail.com>
Reviewed-by: Masashi Honma <masashi.honma@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

On pre-emption enabled kernels the following print was being seen due to
missing local_bh_disable/local_bh_enable calls.  mac80211 assumes that
pre-emption is disabled in the data path.

    BUG: using smp_processor_id() in preemptible [00000000] code: iwd/517
    caller is __ieee80211_subif_start_xmit+0x144/0x210 [mac80211]
    [...]
    Call Trace:
    dump_stack+0x5c/0x80
    check_preemption_disabled.cold.0+0x46/0x51
    __ieee80211_subif_start_xmit+0x144/0x210 [mac80211]

Fixes: 91180649 ("mac80211: Add support for tx_control_port")
Signed-off-by: Denis Kenzior <denkenz@gmail.com>
[commit message rewrite, fixes tag]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For ACLs implemented using either FIB rules or FIB entries, the BPF
program needs the FIB lookup status to be able to drop the packet.
Since the bpf_fib_lookup API has not reached a released kernel yet,
change the return code to contain an encoding of the FIB lookup
result and return the nexthop device index in the params struct.

In addition, inform the BPF program of any post FIB lookup reason as
to why the packet needs to go up the stack.

The fib result for unicast routes must have an egress device, so remove
the check that it is non-NULL.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Flag with FLAG_EXPECTED_FAIL the BPF_MAXINSNS tests that cannot be jited
on s390 because they exceed BPF_SIZE_MAX and fail when
CONFIG_BPF_JIT_ALWAYS_ON is set. Also set .expected_errcode to -ENOTSUPP
so the tests pass in that case.
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>