The mlxsw driver relies on NETDEV_CHANGEUPPER events to configure the
device in case a port is enslaved to a master netdev such as bridge or
bond.

Since the driver ignores events unrelated to its ports and their
uppers, it's possible to engineer situations in which the device's data
path differs from the kernel's.

One example to such a situation is when a port is enslaved to a bond
that is already enslaved to a bridge. When the bond was enslaved the
driver ignored the event - as the bond wasn't one of its uppers - and
therefore a bridge port instance isn't created in the device.

Until such configurations are supported forbid them by checking that the
upper device doesn't have uppers of its own.

Fixes: 0d65fc13 ("mlxsw: spectrum: Implement LAG port join/leave")
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reported-by: NNogah Frankel <nogahf@mellanox.com>
Tested-by: NNogah Frankel <nogahf@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Noticed that busy_poll_stop() also invoke the drivers napi->poll()
function pointer, but didn't have an associated call to trace_napi_poll()
like all other call sites.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a few bugs around refcnt handling in the new BPF congestion
control setsockopt:

 - The new ca is assigned to icsk->icsk_ca_ops even in the case where we
   cannot get a reference on it. This would lead to a use after free,
   since that ca is going away soon.

 - Changing the congestion control case doesn't release the refcnt on
   the previous ca.

 - In the reinit case, we first leak a reference on the old ca, then we
   call tcp_reinit_congestion_control on the ca that we have just
   assigned, leading to deinitializing the wrong ca (->release of the
   new ca on the old ca's data) and releasing the refcount on the ca
   that we actually want to use.

This is visible by building (for example) BIC as a module and setting
net.ipv4.tcp_congestion_control=bic, and using tcp_cong_kern.c from
samples/bpf.

This patch fixes the refcount issues, and moves reinit back into tcp
core to avoid passing a ca pointer back to BPF.

Fixes: 91b5b21c ("bpf: Add support for changing congestion control")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Acked-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a bug causing any sock operations to always return EINVAL.

Fixes: a5192c52 ("bpf: fix to bpf_setsockops").
Reported-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Acked-by: NCraig Gallek <kraig@google.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename skb_pad() into __skb_pad() and make it take a third argument:
free_on_error which controls whether kfree_skb() should be called or
not, skb_pad() directly makes use of it and passes true to preserve its
existing behavior. Do exactly the same thing with __skb_put_padto() and
skb_put_padto().
Suggested-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NWoojung Huh <Woojung.Huh@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When peeking, if a bad csum is discovered, the skb is unlinked from
the queue with __sk_queue_drop_skb and the peek operation restarted.

__sk_queue_drop_skb only drops packets that match the queue head.

This fails if the skb was found after the head, using SO_PEEK_OFF
socket option. This causes an infinite loop.

We MUST drop this problematic skb, and we can simply check if skb was
already removed by another thread, by looking at skb->next :

This pointer is set to NULL by the  __skb_unlink() operation, that might
have happened only under the spinlock protection.

Many thanks to syzkaller team (and particularly Dmitry Vyukov who
provided us nice C reproducers exhibiting the lockup) and Willem de
Bruijn who provided first version for this patch and a test program.

Fixes: 627d2d6b ("udp: enable MSG_PEEK at non-zero offset")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Due to commit e6afc8ac ("udp: remove
headers from UDP packets before queueing"), when udp packets are being
peeked the requested extra offset is always 0 as there is no need to skip
the udp header.  However, when the offset is 0 and the next skb is
of length 0, it is only returned once.  The behaviour can be seen with
the following python script:

from socket import *;
f=socket(AF_INET6, SOCK_DGRAM | SOCK_NONBLOCK, 0);
g=socket(AF_INET6, SOCK_DGRAM | SOCK_NONBLOCK, 0);
f.bind(('::', 0));
addr=('::1', f.getsockname()[1]);
g.sendto(b'', addr)
g.sendto(b'b', addr)
print(f.recvfrom(10, MSG_PEEK));
print(f.recvfrom(10, MSG_PEEK));

Where the expected output should be the empty string twice.

Instead, make sk_peek_offset return negative values, and pass those values
to __skb_try_recv_datagram/__skb_try_recv_from_queue.  If the passed offset
to __skb_try_recv_from_queue is negative, the checked skb is never skipped.
__skb_try_recv_from_queue will then ensure the offset is reset back to 0
if a peek is requested without an offset, unless no packets are found.

Also simplify the if condition in __skb_try_recv_from_queue.  If _off is
greater then 0, and off is greater then or equal to skb->len, then
(_off || skb->len) must always be true assuming skb->len >= 0 is always
true.

Also remove a redundant check around a call to sk_peek_offset in af_unix.c,
as it double checked if MSG_PEEK was set in the flags.

V2:
 - Moved the negative fixup into __skb_try_recv_from_queue, and remove now
redundant checks
 - Fix peeking in udp{,v6}_recvmsg to report the right value when the
offset is 0

V3:
 - Marked new branch in __skb_try_recv_from_queue as unlikely.
Signed-off-by: NMatthew Dawson <matthew@mjdsystems.ca>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When CONFIG_NET_SCHED or CONFIG_NET_RX_BUSY_POLL is /not/ set and
we try a narrow __sk_buff load of tc_index or napi_id, respectively,
then verifier rightfully complains that it's misconfigured, because
we need to set target_size in each of the two cases. The rewrite
for the ctx access is just a dummy op, but needs to pass, so fix
this up.

Fixes: f96da094 ("bpf: simplify narrower ctx access")
Reported-by: NShubham Bansal <illusionist.neo@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb_warn_bad_offload triggers a warning when an skb enters the GSO
stack at __skb_gso_segment that does not have CHECKSUM_PARTIAL
checksum offload set.

Commit b2504a5d ("net: reduce skb_warn_bad_offload() noise")
observed that SKB_GSO_DODGY producers can trigger the check and
that passing those packets through the GSO handlers will fix it
up. But, the software UFO handler will set ip_summed to
CHECKSUM_NONE.

When __skb_gso_segment is called from the receive path, this
triggers the warning again.

Make UFO set CHECKSUM_UNNECESSARY instead of CHECKSUM_NONE. On
Tx these two are equivalent. On Rx, this better matches the
skb state (checksum computed), as CHECKSUM_NONE here means no
checksum computed.

See also this thread for context:
http://patchwork.ozlabs.org/patch/799015/

Fixes: b2504a5d ("net: reduce skb_warn_bad_offload() noise")
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Historically, dev_ifsioc() uses struct sockaddr as mac
address definition, this is why dev_set_mac_address()
accepts a struct sockaddr pointer as input but now we
have various types of mac addresse whose lengths
are up to MAX_ADDR_LEN, longer than struct sockaddr,
and saved in dev->addr_len.

It is too late to fix dev_ifsioc() due to API
compatibility, so just reject those larger than
sizeof(struct sockaddr), otherwise we would read
and use some random bytes from kernel stack.

Fortunately, only a few IPv6 tunnel devices have addr_len
larger than sizeof(struct sockaddr) and they don't support
ndo_set_mac_addr(). But with team driver, in lb mode, they
can still be enslaved to a team master and make its mac addr
length as the same.

Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Apparently netpoll_setup() assumes that netpoll.dev_name is a pointer
when checking if the device name is set:

if (np->dev_name) {
  ...

However the field is a character array, therefore the condition always
yields true. Check instead whether the first byte of the array has a
non-zero value.
Signed-off-by: NMatthias Kaehlcke <mka@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

virtnet_set_mac_address() interprets mac address as struct
sockaddr, but upper layer only allocates dev->addr_len
which is ETH_ALEN + sizeof(sa_family_t) in this case.

We lack a unified definition for mac address, so just fix
the upper layer, this also allows drivers to interpret it
to struct sockaddr freely.
Reported-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit cd8966e7.

The duplicate CHANGEADDR event message is sent regardless of link
status whereas the setlink changes only generate a notification when
the link is up. Not sending a notification when the link is down breaks
dhcpcd which only processes hwaddr changes when the link is down.

Fixes reported regression:
    https://bugzilla.kernel.org/show_bug.cgi?id=196355Reported-by: NYaroslav Isakov <yaroslav.isakov@gmail.com>
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ifr.ifr_name is passed around and assumed to be NULL terminated.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ifr name is assumed to be a valid string by the kernel, but nothing
was forcing username to pass a valid string.

In turn, this would cause panics as we tried to access the string
past it's valid memory.
Signed-off-by: NSasha Levin <alexander.levin@verizon.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we convert atomic_t to refcount_t, a new kernel warning
on "increment on 0" is introduced in the netpoll code,
zap_completion_queue(). In fact for this special case, we know
the refcount is 0 and we just have to set it to 1 to satisfy
the following dev_kfree_skb_any(), so we can just use
refcount_set(..., 1) instead.

Fixes: 63354797 ("net: convert sk_buff.users from atomic_t to refcount_t")
Reported-by: NDave Jones <davej@codemonkey.org.uk>
Cc: Reshetova, Elena <elena.reshetova@intel.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The configure callback of fib_rules_ops can change the refcnt of a
fib rule. For instance, mlxsw takes a refcnt when adding the processing
of the rule to a work queue. Thus the rule refcnt can not be reset to
to 1 afterwards. Move the refcnt setting to after the allocation.

Fixes: 5361e209 ("net: avoid one splat in fib_nl_delrule()")
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The bpf_skb_adjust_net() ignores the return value of bpf_skb_net_shrink/grow,
and always return 0, fix it by return 'ret'.
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__GFP_REPEAT was designed to allow retry-but-eventually-fail semantic to
the page allocator.  This has been true but only for allocations
requests larger than PAGE_ALLOC_COSTLY_ORDER.  It has been always
ignored for smaller sizes.  This is a bit unfortunate because there is
no way to express the same semantic for those requests and they are
considered too important to fail so they might end up looping in the
page allocator for ever, similarly to GFP_NOFAIL requests.

Now that the whole tree has been cleaned up and accidental or misled
usage of __GFP_REPEAT flag has been removed for !costly requests we can
give the original flag a better name and more importantly a more useful
semantic.  Let's rename it to __GFP_RETRY_MAYFAIL which tells the user
that the allocator would try really hard but there is no promise of a
success.  This will work independent of the order and overrides the
default allocator behavior.  Page allocator users have several levels of
guarantee vs.  cost options (take GFP_KERNEL as an example)

 - GFP_KERNEL & ~__GFP_RECLAIM - optimistic allocation without _any_
   attempt to free memory at all. The most light weight mode which even
   doesn't kick the background reclaim. Should be used carefully because
   it might deplete the memory and the next user might hit the more
   aggressive reclaim

 - GFP_KERNEL & ~__GFP_DIRECT_RECLAIM (or GFP_NOWAIT)- optimistic
   allocation without any attempt to free memory from the current
   context but can wake kswapd to reclaim memory if the zone is below
   the low watermark. Can be used from either atomic contexts or when
   the request is a performance optimization and there is another
   fallback for a slow path.

 - (GFP_KERNEL|__GFP_HIGH) & ~__GFP_DIRECT_RECLAIM (aka GFP_ATOMIC) -
   non sleeping allocation with an expensive fallback so it can access
   some portion of memory reserves. Usually used from interrupt/bh
   context with an expensive slow path fallback.

 - GFP_KERNEL - both background and direct reclaim are allowed and the
   _default_ page allocator behavior is used. That means that !costly
   allocation requests are basically nofail but there is no guarantee of
   that behavior so failures have to be checked properly by callers
   (e.g. OOM killer victim is allowed to fail currently).

 - GFP_KERNEL | __GFP_NORETRY - overrides the default allocator behavior
   and all allocation requests fail early rather than cause disruptive
   reclaim (one round of reclaim in this implementation). The OOM killer
   is not invoked.

 - GFP_KERNEL | __GFP_RETRY_MAYFAIL - overrides the default allocator
   behavior and all allocation requests try really hard. The request
   will fail if the reclaim cannot make any progress. The OOM killer
   won't be triggered.

 - GFP_KERNEL | __GFP_NOFAIL - overrides the default allocator behavior
   and all allocation requests will loop endlessly until they succeed.
   This might be really dangerous especially for larger orders.

Existing users of __GFP_REPEAT are changed to __GFP_RETRY_MAYFAIL
because they already had their semantic.  No new users are added.
__alloc_pages_slowpath is changed to bail out for __GFP_RETRY_MAYFAIL if
there is no progress and we have already passed the OOM point.

This means that all the reclaim opportunities have been exhausted except
the most disruptive one (the OOM killer) and a user defined fallback
behavior is more sensible than keep retrying in the page allocator.

[akpm@linux-foundation.org: fix arch/sparc/kernel/mdesc.c]
[mhocko@suse.com: semantic fix]
  Link: http://lkml.kernel.org/r/20170626123847.GM11534@dhcp22.suse.cz
[mhocko@kernel.org: address other thing spotted by Vlastimil]
  Link: http://lkml.kernel.org/r/20170626124233.GN11534@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20170623085345.11304-3-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: NeilBrown <neilb@suse.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

An underscore in the kernel-doc comment section has special meaning
and mis-use generates an errors.

./net/core/datagram.c:207: ERROR: Unknown target name: "msg".
./net/core/datagram.c:379: ERROR: Unknown target name: "msg".
./net/core/datagram.c:816: ERROR: Unknown target name: "t".
Signed-off-by: NStephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As Hongjun/Nicolas summarized in their original patch:

"
When a device changes from one netns to another, it's first unregistered,
then the netns reference is updated and the dev is registered in the new
netns. Thus, when a slave moves to another netns, it is first
unregistered. This triggers a NETDEV_UNREGISTER event which is caught by
the bonding driver. The driver calls bond_release(), which calls
dev_set_mtu() and thus triggers NETDEV_CHANGEMTU (the device is still in
the old netns).
"

This is a very special case, because the device is being unregistered
no one should still care about the NETDEV_CHANGEMTU event triggered
at this point, we can avoid broadcasting this event on this path,
and avoid touching inetdev_event()/addrconf_notify() path.

It requires to export __dev_set_mtu() to bonding driver.
Reported-by: NHongjun Li <hongjun.li@6wind.com>
Reported-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There appears to be a missing break in the TCP_BPF_SNDCWND_CLAMP case.
Currently the non-error path where val is greater than zero falls through
to the default case that sets the error return to -EINVAL. Add in
the missing break.

Detected by CoverityScan, CID#1449376 ("Missing break in switch")

Fixes: 13bf9641 ("bpf: Adds support for setting sndcwnd clamp")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to use refcount_set() on a newly created rule to avoid
following error :

[   64.601749] ------------[ cut here ]------------
[   64.601757] WARNING: CPU: 0 PID: 6476 at lib/refcount.c:184 refcount_sub_and_test+0x75/0xa0
[   64.601758] Modules linked in: w1_therm wire cdc_acm ehci_pci ehci_hcd mlx4_en ib_uverbs mlx4_ib ib_core mlx4_core
[   64.601769] CPU: 0 PID: 6476 Comm: ip Tainted: G        W       4.12.0-smp-DEV #274
[   64.601771] task: ffff8837bf482040 task.stack: ffff8837bdc08000
[   64.601773] RIP: 0010:refcount_sub_and_test+0x75/0xa0
[   64.601774] RSP: 0018:ffff8837bdc0f5c0 EFLAGS: 00010286
[   64.601776] RAX: 0000000000000026 RBX: 0000000000000001 RCX: 0000000000000000
[   64.601777] RDX: 0000000000000026 RSI: 0000000000000096 RDI: ffffed06f7b81eae
[   64.601778] RBP: ffff8837bdc0f5d0 R08: 0000000000000004 R09: fffffbfff4a54c25
[   64.601779] R10: 00000000cbc500e5 R11: ffffffffa52a6128 R12: ffff881febcf6f24
[   64.601779] R13: ffff881fbf4eaf00 R14: ffff881febcf6f80 R15: ffff8837d7a4ed00
[   64.601781] FS:  00007ff5a2f6b700(0000) GS:ffff881fff800000(0000) knlGS:0000000000000000
[   64.601782] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   64.601783] CR2: 00007ffcdc70d000 CR3: 0000001f9c91e000 CR4: 00000000001406f0
[   64.601783] Call Trace:
[   64.601786]  refcount_dec_and_test+0x11/0x20
[   64.601790]  fib_nl_delrule+0xc39/0x1630
[   64.601793]  ? is_bpf_text_address+0xe/0x20
[   64.601795]  ? fib_nl_newrule+0x25e0/0x25e0
[   64.601798]  ? depot_save_stack+0x133/0x470
[   64.601801]  ? ns_capable+0x13/0x20
[   64.601803]  ? __netlink_ns_capable+0xcc/0x100
[   64.601806]  rtnetlink_rcv_msg+0x23a/0x6a0
[   64.601808]  ? rtnl_newlink+0x1630/0x1630
[   64.601811]  ? memset+0x31/0x40
[   64.601813]  netlink_rcv_skb+0x2d7/0x440
[   64.601815]  ? rtnl_newlink+0x1630/0x1630
[   64.601816]  ? netlink_ack+0xaf0/0xaf0
[   64.601818]  ? kasan_unpoison_shadow+0x35/0x50
[   64.601820]  ? __kmalloc_node_track_caller+0x4c/0x70
[   64.601821]  rtnetlink_rcv+0x28/0x30
[   64.601823]  netlink_unicast+0x422/0x610
[   64.601824]  ? netlink_attachskb+0x650/0x650
[   64.601826]  netlink_sendmsg+0x7b7/0xb60
[   64.601828]  ? netlink_unicast+0x610/0x610
[   64.601830]  ? netlink_unicast+0x610/0x610
[   64.601832]  sock_sendmsg+0xba/0xf0
[   64.601834]  ___sys_sendmsg+0x6a9/0x8c0
[   64.601835]  ? copy_msghdr_from_user+0x520/0x520
[   64.601837]  ? __alloc_pages_nodemask+0x160/0x520
[   64.601839]  ? memcg_write_event_control+0xd60/0xd60
[   64.601841]  ? __alloc_pages_slowpath+0x1d50/0x1d50
[   64.601843]  ? kasan_slab_free+0x71/0xc0
[   64.601845]  ? mem_cgroup_commit_charge+0xb2/0x11d0
[   64.601847]  ? lru_cache_add_active_or_unevictable+0x7d/0x1a0
[   64.601849]  ? __handle_mm_fault+0x1af8/0x2810
[   64.601851]  ? may_open_dev+0xc0/0xc0
[   64.601852]  ? __pmd_alloc+0x2c0/0x2c0
[   64.601853]  ? __fdget+0x13/0x20
[   64.601855]  __sys_sendmsg+0xc6/0x150
[   64.601856]  ? __sys_sendmsg+0xc6/0x150
[   64.601857]  ? SyS_shutdown+0x170/0x170
[   64.601859]  ? handle_mm_fault+0x28a/0x650
[   64.601861]  SyS_sendmsg+0x12/0x20
[   64.601863]  entry_SYSCALL_64_fastpath+0x13/0x94

Fixes: 717d1e99 ("net: convert fib_rule.refcnt from atomic_t to refcount_t")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 9256645a ("net/core: relax BUILD_BUG_ON in
netdev_stats_to_stats64") made an attempt to read beyond
the size of the source a possibility.

Fix to only copy src size to dest. As dest might be bigger than src.

 ==================================================================
 BUG: KASAN: slab-out-of-bounds in netdev_stats_to_stats64+0xe/0x30 at addr ffff8801be248b20
 Read of size 192 by task VBoxNetAdpCtl/6734
 CPU: 1 PID: 6734 Comm: VBoxNetAdpCtl Tainted: G           O    4.11.4prahal+intel+ #118
 Hardware name: LENOVO 20CDCTO1WW/20CDCTO1WW, BIOS GQET52WW (1.32 ) 05/04/2017
 Call Trace:
  dump_stack+0x63/0x86
  kasan_object_err+0x1c/0x70
  kasan_report+0x270/0x520
  ? netdev_stats_to_stats64+0xe/0x30
  ? sched_clock_cpu+0x1b/0x190
  ? __module_address+0x3e/0x3b0
  ? unwind_next_frame+0x1ea/0xb00
  check_memory_region+0x13c/0x1a0
  memcpy+0x23/0x50
  netdev_stats_to_stats64+0xe/0x30
  dev_get_stats+0x1b9/0x230
  rtnl_fill_stats+0x44/0xc00
  ? nla_put+0xc6/0x130
  rtnl_fill_ifinfo+0xe9e/0x3700
  ? rtnl_fill_vfinfo+0xde0/0xde0
  ? sched_clock+0x9/0x10
  ? sched_clock+0x9/0x10
  ? sched_clock_local+0x120/0x130
  ? __module_address+0x3e/0x3b0
  ? unwind_next_frame+0x1ea/0xb00
  ? sched_clock+0x9/0x10
  ? sched_clock+0x9/0x10
  ? sched_clock_cpu+0x1b/0x190
  ? VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  ? depot_save_stack+0x1d8/0x4a0
  ? depot_save_stack+0x34f/0x4a0
  ? depot_save_stack+0x34f/0x4a0
  ? save_stack+0xb1/0xd0
  ? save_stack_trace+0x16/0x20
  ? save_stack+0x46/0xd0
  ? kasan_slab_alloc+0x12/0x20
  ? __kmalloc_node_track_caller+0x10d/0x350
  ? __kmalloc_reserve.isra.36+0x2c/0xc0
  ? __alloc_skb+0xd0/0x560
  ? rtmsg_ifinfo_build_skb+0x61/0x120
  ? rtmsg_ifinfo.part.25+0x16/0xb0
  ? rtmsg_ifinfo+0x47/0x70
  ? register_netdev+0x15/0x30
  ? vboxNetAdpOsCreate+0xc0/0x1c0 [vboxnetadp]
  ? vboxNetAdpCreate+0x210/0x400 [vboxnetadp]
  ? VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  ? do_vfs_ioctl+0x17f/0xff0
  ? SyS_ioctl+0x74/0x80
  ? do_syscall_64+0x182/0x390
  ? __alloc_skb+0xd0/0x560
  ? __alloc_skb+0xd0/0x560
  ? save_stack_trace+0x16/0x20
  ? init_object+0x64/0xa0
  ? ___slab_alloc+0x1ae/0x5c0
  ? ___slab_alloc+0x1ae/0x5c0
  ? __alloc_skb+0xd0/0x560
  ? sched_clock+0x9/0x10
  ? kasan_unpoison_shadow+0x35/0x50
  ? kasan_kmalloc+0xad/0xe0
  ? __kmalloc_node_track_caller+0x246/0x350
  ? __alloc_skb+0xd0/0x560
  ? kasan_unpoison_shadow+0x35/0x50
  ? memset+0x31/0x40
  ? __alloc_skb+0x31f/0x560
  ? napi_consume_skb+0x320/0x320
  ? br_get_link_af_size_filtered+0xb7/0x120 [bridge]
  ? if_nlmsg_size+0x440/0x630
  rtmsg_ifinfo_build_skb+0x83/0x120
  rtmsg_ifinfo.part.25+0x16/0xb0
  rtmsg_ifinfo+0x47/0x70
  register_netdevice+0xa2b/0xe50
  ? __kmalloc+0x171/0x2d0
  ? netdev_change_features+0x80/0x80
  register_netdev+0x15/0x30
  vboxNetAdpOsCreate+0xc0/0x1c0 [vboxnetadp]
  vboxNetAdpCreate+0x210/0x400 [vboxnetadp]
  ? vboxNetAdpComposeMACAddress+0x1d0/0x1d0 [vboxnetadp]
  ? kasan_check_write+0x14/0x20
  VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  ? VBoxNetAdpLinuxOpen+0x20/0x20 [vboxnetadp]
  ? lock_acquire+0x11c/0x270
  ? __audit_syscall_entry+0x2fb/0x660
  do_vfs_ioctl+0x17f/0xff0
  ? __audit_syscall_entry+0x2fb/0x660
  ? ioctl_preallocate+0x1d0/0x1d0
  ? __audit_syscall_entry+0x2fb/0x660
  ? kmem_cache_free+0xb2/0x250
  ? syscall_trace_enter+0x537/0xd00
  ? exit_to_usermode_loop+0x100/0x100
  SyS_ioctl+0x74/0x80
  ? do_sys_open+0x350/0x350
  ? do_vfs_ioctl+0xff0/0xff0
  do_syscall_64+0x182/0x390
  entry_SYSCALL64_slow_path+0x25/0x25
 RIP: 0033:0x7f7e39a1ae07
 RSP: 002b:00007ffc6f04c6d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
 RAX: ffffffffffffffda RBX: 00007ffc6f04c730 RCX: 00007f7e39a1ae07
 RDX: 00007ffc6f04c730 RSI: 00000000c0207601 RDI: 0000000000000007
 RBP: 00007ffc6f04c700 R08: 00007ffc6f04c780 R09: 0000000000000008
 R10: 0000000000000541 R11: 0000000000000206 R12: 0000000000000007
 R13: 00000000c0207601 R14: 00007ffc6f04c730 R15: 0000000000000012
 Object at ffff8801be248008, in cache kmalloc-4096 size: 4096
 Allocated:
 PID = 6734
  save_stack_trace+0x16/0x20
  save_stack+0x46/0xd0
  kasan_kmalloc+0xad/0xe0
  __kmalloc+0x171/0x2d0
  alloc_netdev_mqs+0x8a7/0xbe0
  vboxNetAdpOsCreate+0x65/0x1c0 [vboxnetadp]
  vboxNetAdpCreate+0x210/0x400 [vboxnetadp]
  VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  do_vfs_ioctl+0x17f/0xff0
  SyS_ioctl+0x74/0x80
  do_syscall_64+0x182/0x390
  return_from_SYSCALL_64+0x0/0x6a
 Freed:
 PID = 5600
  save_stack_trace+0x16/0x20
  save_stack+0x46/0xd0
  kasan_slab_free+0x73/0xc0
  kfree+0xe4/0x220
  kvfree+0x25/0x30
  single_release+0x74/0xb0
  __fput+0x265/0x6b0
  ____fput+0x9/0x10
  task_work_run+0xd5/0x150
  exit_to_usermode_loop+0xe2/0x100
  do_syscall_64+0x26c/0x390
  return_from_SYSCALL_64+0x0/0x6a
 Memory state around the buggy address:
  ffff8801be248a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff8801be248b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 >ffff8801be248b80: 00 00 00 00 00 00 00 00 00 00 00 07 fc fc fc fc
                                                     ^
  ffff8801be248c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff8801be248c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ==================================================================
Signed-off-by: NAlban Browaeys <alban.browaeys@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This work tries to make the semantics and code around the
narrower ctx access a bit easier to follow. Right now
everything is done inside the .is_valid_access(). Offset
matching is done differently for read/write types, meaning
writes don't support narrower access and thus matching only
on offsetof(struct foo, bar) is enough whereas for read
case that supports narrower access we must check for
offsetof(struct foo, bar) + offsetof(struct foo, bar) +
sizeof(<bar>) - 1 for each of the cases. For read cases of
individual members that don't support narrower access (like
packet pointers or skb->cb[] case which has its own narrow
access logic), we check as usual only offsetof(struct foo,
bar) like in write case. Then, for the case where narrower
access is allowed, we also need to set the aux info for the
access. Meaning, ctx_field_size and converted_op_size have
to be set. First is the original field size e.g. sizeof(<bar>)
as in above example from the user facing ctx, and latter
one is the target size after actual rewrite happened, thus
for the kernel facing ctx. Also here we need the range match
and we need to keep track changing convert_ctx_access() and
converted_op_size from is_valid_access() as both are not at
the same location.

We can simplify the code a bit: check_ctx_access() becomes
simpler in that we only store ctx_field_size as a meta data
and later in convert_ctx_accesses() we fetch the target_size
right from the location where we do convert. Should the verifier
be misconfigured we do reject for BPF_WRITE cases or target_size
that are not provided. For the subsystems, we always work on
ranges in is_valid_access() and add small helpers for ranges
and narrow access, convert_ctx_accesses() sets target_size
for the relevant instruction.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Cc: Yonghong Song <yhs@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This work adds a helper that can be used to adjust net room of an
skb. The helper is generic and can be further extended in future.
Main use case is for having a programmatic way to add/remove room to
v4/v6 header options along with cls_bpf on egress and ingress hook
of the data path. It reuses most of the infrastructure that we added
for the bpf_skb_change_type() helper which can be used in nat64
translations. Similarly, the helper only takes care of adjusting the
room so that related data is populated and csum adapted out of the
BPF program using it.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a small skb_mac_header_len() helper similarly as the
skb_network_header_len() we have and replace open coded
places in BPF's bpf_skb_change_proto() helper. Will also
be used in upcoming work.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixed build error due to misplaced "#ifdef CONFIG_INET" (moved 1
statement up).
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds a new bpf_setsockopt for TCP sockets, TCP_BPF_SNDCWND_CLAMP, which
sets the initial congestion window. It is useful to limit the sndcwnd
when the host are close to each other (small RTT).
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds a new bpf_setsockopt for TCP sockets, TCP_BPF_IW, which sets the
initial congestion window. This can be used when the hosts are far
apart (large RTTs) and it is safe to start with a large inital cwnd.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Added support for changing congestion control for SOCK_OPS bpf
programs through the setsockopt bpf helper function. It also adds
a new SOCK_OPS op, BPF_SOCK_OPS_NEEDS_ECN, that is needed for
congestion controls, like dctcp, that need to enable ECN in the
SYN packets.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Added support for calling a subset of socket setsockopts from
BPF_PROG_TYPE_SOCK_OPS programs. The code was duplicated rather
than making the changes to call the socket setsockopt function because
the changes required would have been larger.

The ops supported are:
  SO_RCVBUF
  SO_SNDBUF
  SO_MAX_PACING_RATE
  SO_PRIORITY
  SO_RCVLOWAT
  SO_MARK
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Created a new BPF program type, BPF_PROG_TYPE_SOCK_OPS, and a corresponding
struct that allows BPF programs of this type to access some of the
socket's fields (such as IP addresses, ports, etc.). It uses the
existing bpf cgroups infrastructure so the programs can be attached per
cgroup with full inheritance support. The program will be called at
appropriate times to set relevant connections parameters such as buffer
sizes, SYN and SYN-ACK RTOs, etc., based on connection information such
as IP addresses, port numbers, etc.

Alghough there are already 3 mechanisms to set parameters (sysctls,
route metrics and setsockopts), this new mechanism provides some
distinct advantages. Unlike sysctls, it can set parameters per
connection. In contrast to route metrics, it can also use port numbers
and information provided by a user level program. In addition, it could
set parameters probabilistically for evaluation purposes (i.e. do
something different on 10% of the flows and compare results with the
other 90% of the flows). Also, in cases where IPv6 addresses contain
geographic information, the rules to make changes based on the distance
(or RTT) between the hosts are much easier than route metric rules and
can be global. Finally, unlike setsockopt, it oes not require
application changes and it can be updated easily at any time.

Although the bpf cgroup framework already contains a sock related
program type (BPF_PROG_TYPE_CGROUP_SOCK), I created the new type
(BPF_PROG_TYPE_SOCK_OPS) beccause the existing type expects to be called
only once during the connections's lifetime. In contrast, the new
program type will be called multiple times from different places in the
network stack code.  For example, before sending SYN and SYN-ACKs to set
an appropriate timeout, when the connection is established to set
congestion control, etc. As a result it has "op" field to specify the
type of operation requested.

The purpose of this new program type is to simplify setting connection
parameters, such as buffer sizes, TCP's SYN RTO, etc. For example, it is
easy to use facebook's internal IPv6 addresses to determine if both hosts
of a connection are in the same datacenter. Therefore, it is easy to
write a BPF program to choose a small SYN RTO value when both hosts are
in the same datacenter.

This patch only contains the framework to support the new BPF program
type, following patches add the functionality to set various connection
parameters.

This patch defines a new BPF program type: BPF_PROG_TYPE_SOCKET_OPS
and a new bpf syscall command to load a new program of this type:
BPF_PROG_LOAD_SOCKET_OPS.

Two new corresponding structs (one for the kernel one for the user/BPF
program):

/* kernel version */
struct bpf_sock_ops_kern {
        struct sock *sk;
        __u32  op;
        union {
                __u32 reply;
                __u32 replylong[4];
        };
};

/* user version
 * Some fields are in network byte order reflecting the sock struct
 * Use the bpf_ntohl helper macro in samples/bpf/bpf_endian.h to
 * convert them to host byte order.
 */
struct bpf_sock_ops {
        __u32 op;
        union {
                __u32 reply;
                __u32 replylong[4];
        };
        __u32 family;
        __u32 remote_ip4;     /* In network byte order */
        __u32 local_ip4;      /* In network byte order */
        __u32 remote_ip6[4];  /* In network byte order */
        __u32 local_ip6[4];   /* In network byte order */
        __u32 remote_port;    /* In network byte order */
        __u32 local_port;     /* In host byte horder */
};

Currently there are two types of ops. The first type expects the BPF
program to return a value which is then used by the caller (or a
negative value to indicate the operation is not supported). The second
type expects state changes to be done by the BPF program, for example
through a setsockopt BPF helper function, and they ignore the return
value.

The reply fields of the bpf_sockt_ops struct are there in case a bpf
program needs to return a value larger than an integer.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

This patch uses refcount_inc_not_zero() instead of
atomic_inc_not_zero_hint() due to absense of a _hint()
version of refcount API. If the hint() version must
be used, we might need to revisit API.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>