Recently I started seeing warnings about pages with refcount -1. The
problem was traced to packets being reused after their head was merged into
a GRO packet by skb_gro_receive(). While bisecting the issue pointed to
commit c21b48cc1b ("net: adjust skb->truesize in ___pskb_trim()") and
I have never seen it on a kernel with it reverted, I believe the real
problem appeared earlier when the option to merge head frag in GRO was
implemented.
Handling NAPI_GRO_FREE_STOLEN_HEAD state was only added to GRO_MERGED_FREE
branch of napi_skb_finish() so that if the driver uses napi_gro_frags()
and head is merged (which in my case happens after the skb_condense()
call added by the commit mentioned above), the skb is reused including the
head that has been merged. As a result, we release the page reference
twice and eventually end up with negative page refcount.
To fix the problem, handle NAPI_GRO_FREE_STOLEN_HEAD in napi_frags_finish()
the same way it's done in napi_skb_finish().
Fixes: d7e8883cfc ("net: make GRO aware of skb->head_frag")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to the fix provided by Dominik Heidler in commit
9b3dc0a17d ("l2tp: cast l2tp traffic counter to unsigned")
we need to take care of 32bit kernels in dev_get_stats().
When using atomic_long_read(), we add a 'long' to u64 and
might misinterpret high order bit, unless we cast to unsigned.
Fixes: caf586e5f2 ("net: add a core netdev->rx_dropped counter")
Fixes: 015f0688f5 ("net: net: add a core netdev->tx_dropped counter")
Fixes: 6e7333d315 ("net: add rx_nohandler stat counter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Network interface groups support added while ago, however
there is no IFLA_GROUP attribute description in policy
and netlink message size calculations until now.
Add IFLA_GROUP attribute to the policy.
Fixes: cbda10fa97 ("net_device: add support for network device groups")
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 217f697436 ("net: busy-poll: allow preemption in
sk_busy_loop()") there is an explicit do_softirq() invocation after
local_bh_enable() has been invoked.
I don't understand why we need this because local_bh_enable() will
invoke do_softirq() once the softirq counter reached zero and we have
softirq-related work pending.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should avoid marking goto rules unresolved when their
target is actually reachable after rule deletion.
Consolder following sample scenario:
# ip -4 ru sh
0: from all lookup local
32000: from all goto 32100
32100: from all lookup main
32100: from all lookup default
32766: from all lookup main
32767: from all lookup default
# ip -4 ru del pref 32100 table main
# ip -4 ru sh
0: from all lookup local
32000: from all goto 32100 [unresolved]
32100: from all lookup default
32766: from all lookup main
32767: from all lookup default
After removal of first rule with preference 32100 we
mark all goto rules as unreachable, even when rule with
same preference as removed one still present.
Check if next rule with same preference is available
and make all rules with goto action pointing to it.
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unfortunately, struct iwreq isn't a proper subset of struct ifreq,
but is still handled by the same code path. Robert reported that
then applications may (randomly) fault if the struct iwreq they
pass happens to land within 8 bytes of the end of a mapping (the
struct is only 32 bytes, vs. struct ifreq's 40 bytes).
To fix this, pull out the code handling wireless extension ioctls
and copy only the smaller structure in this case.
This bug goes back a long time, I tracked that it was introduced
into mainline in 2.1.15, over 20 years ago!
This fixes https://bugzilla.kernel.org/show_bug.cgi?id=195869
Reported-by: Robert O'Callahan <robert@ocallahan.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This patch fixes uninitialized symbol warning that
got introduced by the following commit
773fc8f6e8 ("net: rps: send out pending IPI's on CPU hotplug")
Signed-off-by: Ashwanth Goli <ashwanth@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPI's from the victim cpu are not handled in dev_cpu_callback.
So these pending IPI's would be sent to the remote cpu only when
NET_RX is scheduled on the victim cpu and since this trigger is
unpredictable it would result in packet latencies on the remote cpu.
This patch add support to send the pending ipi's of victim cpu.
Signed-off-by: Ashwanth Goli <ashwanth@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It looks like this:
Message from syslogd@flamingo at Apr 26 00:45:00 ...
kernel:unregister_netdevice: waiting for lo to become free. Usage count = 4
They seem to coincide with net namespace teardown.
The message is emitted by netdev_wait_allrefs().
Forced a kdump in netdev_run_todo, but found that the refcount on the lo
device was already 0 at the time we got to the panic.
Used bcc to check the blocking in netdev_run_todo. The only places
where we're off cpu there are in the rcu_barrier() and msleep() calls.
That behavior is expected. The msleep time coincides with the amount of
time we spend waiting for the refcount to reach zero; the rcu_barrier()
wait times are not excessive.
After looking through the list of callbacks that the netdevice notifiers
invoke in this path, it appears that the dst_dev_event is the most
interesting. The dst_ifdown path places a hold on the loopback_dev as
part of releasing the dev associated with the original dst cache entry.
Most of our notifier callbacks are straight-forward, but this one a)
looks complex, and b) places a hold on the network interface in
question.
I constructed a new bcc script that watches various events in the
liftime of a dst cache entry. Note that dst_ifdown will take a hold on
the loopback device until the invalidated dst entry gets freed.
[ __dst_free] on DST: ffff883ccabb7900 IF tap1008300eth0 invoked at 1282115677036183
__dst_free
rcu_nocb_kthread
kthread
ret_from_fork
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some of the structure's fields are not initialized by the
rtnetlink. If driver doesn't set those in ndo_get_vf_config(),
they'd leak memory to user.
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
CC: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init(). However, the release of these resources
can occur in one of two different places.
Either netdev_ops->ndo_uninit() or netdev->destructor().
The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.
netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.
netdev->destructor(), on the other hand, does not run until the
netdev references all go away.
Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().
This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.
If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit(). But
it is not able to invoke netdev->destructor().
This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.
However, this means that the resources that would normally be released
by netdev->destructor() will not be.
Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.
Many drivers do not try to deal with this, and instead we have leaks.
Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().
netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().
netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().
Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().
And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().
Signed-off-by: David S. Miller <davem@davemloft.net>
KMSAN reported a use of uninitialized memory in dev_set_alias(),
which was caused by calling strlcpy() (which in turn called strlen())
on the user-supplied non-terminated string.
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We must free allocated skb when genlmsg_put() return fails.
Fixes: 1555d204e7 ("devlink: Support for pipeline debug (dpipe)")
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prior to f5f99309fa (sock: do not set sk_err in
sock_dequeue_err_skb), sk_err was reset to the error of
the skb on the head of the error queue.
Applications, most notably ping, are relying on this
behavior to reset sk_err for ICMP packets.
Set sk_err to the ICMP error when there is an ICMP packet
at the head of the error queue.
Fixes: f5f99309fa (sock: do not set sk_err in sock_dequeue_err_skb)
Reported-by: Cyril Hrubis <chrubis@suse.cz>
Tested-by: Cyril Hrubis <chrubis@suse.cz>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey Konovalov reported crashes in ipv4_mtu()
I could reproduce the issue with KASAN kernels, between
10.246.7.151 and 10.246.7.152 :
1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 &
2) At the same time run following loop :
while :
do
ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500
ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500
done
Cong Wang attempted to add back rt->fi in commit
82486aa6f1 ("ipv4: restore rt->fi for reference counting")
but this proved to add some issues that were complex to solve.
Instead, I suggested to add a refcount to the metrics themselves,
being a standalone object (in particular, no reference to other objects)
I tried to make this patch as small as possible to ease its backport,
instead of being super clean. Note that we believe that only ipv4 dst
need to take care of the metric refcount. But if this is wrong,
this patch adds the basic infrastructure to extend this to other
families.
Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang
for his efforts on this problem.
Fixes: 2860583fe8 ("ipv4: Kill rt->fi")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bpf_clone_redirect() still needs to be listed in
bpf_helper_changes_pkt_data() since we call into
bpf_try_make_head_writable() from there, thus we need
to invalidate prior pkt regs as well.
Fixes: 36bbef52c7 ("bpf: direct packet write and access for helpers for clsact progs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The default value for somaxconn is set in sysctl_core_net_init(), but this
function is not called when kernel is configured without CONFIG_SYSCTL.
This results in the kernel not being able to accept TCP connections,
because the backlog has zero size. Usually, the user ends up with:
"TCP: request_sock_TCP: Possible SYN flooding on port 7. Dropping request. Check SNMP counters."
If SYN cookies are not enabled the connection is rejected.
Before ef547f2ac1 (tcp: remove max_qlen_log), the effects were less
severe, because the backlog was always at least eight slots long.
Signed-off-by: Roman Kapl <roman.kapl@sysgo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If CONFIG_INET is not set, net/core/sock.c can not compile :
net/core/sock.c: In function ‘skb_orphan_partial’:
net/core/sock.c:1810:2: error: implicit declaration of function
‘skb_is_tcp_pure_ack’ [-Werror=implicit-function-declaration]
if (skb_is_tcp_pure_ack(skb))
^
Fix this by always including <net/tcp.h>
Fixes: f6ba8d33cf ("netem: fix skb_orphan_partial()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's a common practice to send gratuitous ARPs after moving an
IP address to another device to speed up healing of a service. To
fulfill service availability constraints, the timing of network peers
updating their caches to point to a new location of an IP address can be
particularly important.
Sometimes neigh_update calls won't touch neither lladdr nor state, for
example if an update arrives in locktime interval. The neigh->updated
value is tested by the protocol specific neigh code, which in turn
will influence whether NEIGH_UPDATE_F_OVERRIDE gets set in the
call to neigh_update() or not. As a result, we may effectively ignore
the update request, bailing out of touching the neigh entry, except that
we still bump its timestamps inside neigh_update.
This may be a problem for updates arriving in quick succession. For
example, consider the following scenario:
A service is moved to another device with its IP address. The new device
sends three gratuitous ARP requests into the network with ~1 seconds
interval between them. Just before the first request arrives to one of
network peer nodes, its neigh entry for the IP address transitions from
STALE to DELAY. This transition, among other things, updates
neigh->updated. Once the kernel receives the first gratuitous ARP, it
ignores it because its arrival time is inside the locktime interval. The
kernel still bumps neigh->updated. Then the second gratuitous ARP
request arrives, and it's also ignored because it's still in the (new)
locktime interval. Same happens for the third request. The node
eventually heals itself (after delay_first_probe_time seconds since the
initial transition to DELAY state), but it just wasted some time and
require a new ARP request/reply round trip. This unfortunate behaviour
both puts more load on the network, as well as reduces service
availability.
This patch changes neigh_update so that it bumps neigh->updated (as well
as neigh->confirmed) only once we are sure that either lladdr or entry
state will change). In the scenario described above, it means that the
second gratuitous ARP request will actually update the entry lladdr.
Ideally, we would update the neigh entry on the very first gratuitous
ARP request. The locktime mechanism is designed to ignore ARP updates in
a short timeframe after a previous ARP update was honoured by the kernel
layer. This would require tracking timestamps for state transitions
separately from timestamps when actual updates are received. This would
probably involve changes in neighbour struct. Therefore, the patch
doesn't tackle the issue of the first gratuitous APR ignored, leaving
it for a follow-up.
Signed-off-by: Ihar Hrachyshka <ihrachys@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In general, rtnetlink dumps do not anticipate failure to dump a single
object (e.g., link or route) on a single pass. As both route and link
objects have grown via more attributes, that is no longer a given.
netlink dumps can handle a failure if the dump function returns an
error; specifically, netlink_dump adds the return code to the response
if it is <= 0 so userspace is notified of the failure. The missing
piece is the rtnetlink dump functions returning the error.
Fix route and link dump functions to return the errors if no object is
added to an skb (detected by skb->len != 0). IPv6 route dumps
(rt6_dump_route) already return the error; this patch updates IPv4 and
link dumps. Other dump functions may need to be ajusted as well.
Reported-by: Jan Moskyto Matejka <mq@ucw.cz>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I should have known that lowering skb->truesize was dangerous :/
In case packets are not leaving the host via a standard Ethernet device,
but looped back to local sockets, bad things can happen, as reported
by Michael Madsen ( https://bugzilla.kernel.org/show_bug.cgi?id=195713 )
So instead of tweaking skb->truesize, lets change skb->destructor
and keep a reference on the owner socket via its sk_refcnt.
Fixes: f2f872f927 ("netem: Introduce skb_orphan_partial() helper")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Michael Madsen <mkm@nabto.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While working on the iproute2 generic XDP frontend, I noticed that
as of right now it's possible to have native *and* generic XDP
programs loaded both at the same time for the case when a driver
supports native XDP.
The intended model for generic XDP from b5cdae3291 ("net: Generic
XDP") is, however, that only one out of the two can be present at
once which is also indicated as such in the XDP netlink dump part.
The main rationale for generic XDP is to ease accessibility (in
case a driver does not yet have XDP support) and to generically
provide a semantical model as an example for driver developers
wanting to add XDP support. The generic XDP option for an XDP
aware driver can still be useful for comparing and testing both
implementations.
However, it is not intended to have a second XDP processing stage
or layer with exactly the same functionality of the first native
stage. Only reason could be to have a partial fallback for future
XDP features that are not supported yet in the native implementation
and we probably also shouldn't strive for such fallback and instead
encourage native feature support in the first place. Given there's
currently no such fallback issue or use case, lets not go there yet
if we don't need to.
Therefore, change semantics for loading XDP and bail out if the
user tries to load a generic XDP program when a native one is
present and vice versa. Another alternative to bailing out would
be to handle the transition from one flavor to another gracefully,
but that would require to bring the device down, exchange both
types of programs, and bring it up again in order to avoid a tiny
window where a packet could hit both hooks. Given this complicates
the logic for just a debugging feature in the native case, I went
with the simpler variant.
For the dump, remove IFLA_XDP_FLAGS that was added with b5cdae3291
and reuse IFLA_XDP_ATTACHED for indicating the mode. Dumping all
or just a subset of flags that were used for loading the XDP prog
is suboptimal in the long run since not all flags are useful for
dumping and if we start to reuse the same flag definitions for
load and dump, then we'll waste bit space. What we really just
want is to dump the mode for now.
Current IFLA_XDP_ATTACHED semantics are: nothing was installed (0),
a program is running at the native driver layer (1). Thus, add a
mode that says that a program is running at generic XDP layer (2).
Applications will handle this fine in that older binaries will
just indicate that something is attached at XDP layer, effectively
this is similar to IFLA_XDP_FLAGS attr that we would have had
modulo the redundancy.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit b5cdae3291 ("net: Generic XDP") we automatically fall
back to a generic XDP variant if the driver does not support native
XDP. Allow for an option where the user can specify that always the
native XDP variant should be selected and in case it's not supported
by a driver, just bail out.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix multiqueue in stmmac driver on PCI, from Andy Shevchenko.
2) cdc_ncm doesn't actually fully zero out the padding area is
allocates on TX, from Jim Baxter.
3) Don't leak map addresses in BPF verifier, from Daniel Borkmann.
4) If we randomize TCP timestamps, we have to do it everywhere
including SYN cookies. From Eric Dumazet.
5) Fix "ethtool -S" crash in aquantia driver, from Pavel Belous.
6) Fix allocation size for ntp filter bitmap in bnxt_en driver, from
Dan Carpenter.
7) Add missing memory allocation return value check to DSA loop driver,
from Christophe Jaillet.
8) Fix XDP leak on driver unload in qed driver, from Suddarsana Reddy
Kalluru.
9) Don't inherit MC list from parent inet connection sockets, another
syzkaller spotted gem. Fix from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits)
dccp/tcp: do not inherit mc_list from parent
qede: Split PF/VF ndos.
qed: Correct doorbell configuration for !4Kb pages
qed: Tell QM the number of tasks
qed: Fix VF removal sequence
qede: Fix XDP memory leak on unload
net/mlx4_core: Reduce harmless SRIOV error message to debug level
net/mlx4_en: Avoid adding steering rules with invalid ring
net/mlx4_en: Change the error print to debug print
drivers: net: wimax: i2400m: i2400m-usb: Use time_after for time comparison
DECnet: Use container_of() for embedded struct
Revert "ipv4: restore rt->fi for reference counting"
net: mdio-mux: bcm-iproc: call mdiobus_free() in error path
net: ethernet: ti: cpsw: adjust cpsw fifos depth for fullduplex flow control
ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf
net: cdc_ncm: Fix TX zero padding
stmmac: pci: split out common_default_data() helper
stmmac: pci: RX queue routing configuration
stmmac: pci: TX and RX queue priority configuration
stmmac: pci: set default number of rx and tx queues
...
We now have memalloc_noreclaim_{save,restore} helpers for robust setting
and clearing of PF_MEMALLOC. Let's convert the code which was using the
generic tsk_restore_flags(). No functional change.
[vbabka@suse.cz: in net/core/sock.c the hunk is missing]
Link: http://lkml.kernel.org/r/20170405074700.29871-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Lee Duncan <lduncan@suse.com>
Cc: Chris Leech <cleech@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Wouter Verhelst <w@uter.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fq_alloc_node, alloc_netdev_mqs and netif_alloc* open code kmalloc with
vmalloc fallback. Use the kvmalloc variant instead. Keep the
__GFP_REPEAT flag based on explanation from Eric:
"At the time, tests on the hardware I had in my labs showed that
vmalloc() could deliver pages spread all over the memory and that was
a small penalty (once memory is fragmented enough, not at boot time)"
The way how the code is constructed means, however, that we prefer to go
and hit the OOM killer before we fall back to the vmalloc for requests
<=32kB (with 4kB pages) in the current code. This is rather disruptive
for something that can be achived with the fallback. On the other hand
__GFP_REPEAT doesn't have any useful semantic for these requests. So
the effect of this patch is that requests which fit into 32kB will fall
back to vmalloc easier now.
Link: http://lkml.kernel.org/r/20170306103327.2766-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Eric Dumazet <edumazet@google.com>
Cc: David Miller <davem@davemloft.net>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Whole point of randomization was to hide server uptime, but an attacker
can simply start a syn flood and TCP generates 'old style' timestamps,
directly revealing server jiffies value.
Also, TSval sent by the server to a particular remote address vary
depending on syncookies being sent or not, potentially triggering PAWS
drops for innocent clients.
Lets implement proper randomization, including for SYNcookies.
Also we do not need to export sysctl_tcp_timestamps, since it is not
used from a module.
In v2, I added Florian feedback and contribution, adding tsoff to
tcp_get_cookie_sock().
v3 removed one unused variable in tcp_v4_connect() as Florian spotted.
Fixes: 95a22caee3 ("tcp: randomize tcp timestamp offsets for each connection")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Tested-by: Florian Westphal <fw@strlen.de>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IFLA_PHYS_PORT_NAME is a string attribute, so terminate it with \0.
Otherwise libnl3 fails to validate netlink messages with this attribute.
"ip -detail a" assumes too that the attribute is NUL-terminated when
printing it. It often was, due to padding.
I noticed this as libvirtd failing to start on a system with sfc driver
after upgrading it to Linux 4.11, i.e. when sfc added support for
phys_port_name.
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking updates from David Millar:
"Here are some highlights from the 2065 networking commits that
happened this development cycle:
1) XDP support for IXGBE (John Fastabend) and thunderx (Sunil Kowuri)
2) Add a generic XDP driver, so that anyone can test XDP even if they
lack a networking device whose driver has explicit XDP support
(me).
3) Sparc64 now has an eBPF JIT too (me)
4) Add a BPF program testing framework via BPF_PROG_TEST_RUN (Alexei
Starovoitov)
5) Make netfitler network namespace teardown less expensive (Florian
Westphal)
6) Add symmetric hashing support to nft_hash (Laura Garcia Liebana)
7) Implement NAPI and GRO in netvsc driver (Stephen Hemminger)
8) Support TC flower offload statistics in mlxsw (Arkadi Sharshevsky)
9) Multiqueue support in stmmac driver (Joao Pinto)
10) Remove TCP timewait recycling, it never really could possibly work
well in the real world and timestamp randomization really zaps any
hint of usability this feature had (Soheil Hassas Yeganeh)
11) Support level3 vs level4 ECMP route hashing in ipv4 (Nikolay
Aleksandrov)
12) Add socket busy poll support to epoll (Sridhar Samudrala)
13) Netlink extended ACK support (Johannes Berg, Pablo Neira Ayuso,
and several others)
14) IPSEC hw offload infrastructure (Steffen Klassert)"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2065 commits)
tipc: refactor function tipc_sk_recv_stream()
tipc: refactor function tipc_sk_recvmsg()
net: thunderx: Optimize page recycling for XDP
net: thunderx: Support for XDP header adjustment
net: thunderx: Add support for XDP_TX
net: thunderx: Add support for XDP_DROP
net: thunderx: Add basic XDP support
net: thunderx: Cleanup receive buffer allocation
net: thunderx: Optimize CQE_TX handling
net: thunderx: Optimize RBDR descriptor handling
net: thunderx: Support for page recycling
ipx: call ipxitf_put() in ioctl error path
net: sched: add helpers to handle extended actions
qed*: Fix issues in the ptp filter config implementation.
qede: Fix concurrency issue in PTP Tx path processing.
stmmac: Add support for SIMATIC IOT2000 platform
net: hns: fix ethtool_get_strings overflow in hns driver
tcp: fix wraparound issue in tcp_lp
bpf, arm64: fix jit branch offset related to ldimm64
bpf, arm64: implement jiting of BPF_XADD
...
Pull splice updates from Al Viro:
"These actually missed the last cycle; the branch itself is from last
December"
* 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
make nr_pages calculation in default_file_splice_read() a bit less ugly
splice/tee/vmsplice: validate flags
splice_pipe_desc: kill ->flags
remove spd_release_page()
Pull iov_iter updates from Al Viro:
"Cleanups that sat in -next + -stable fodder that has just missed 4.11.
There's more iov_iter work in my local tree, but I'd prefer to push
the stuff that had been in -next first"
* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
iov_iter: don't revert iov buffer if csum error
generic_file_read_iter(): make use of iov_iter_revert()
generic_file_direct_write(): make use of iov_iter_revert()
orangefs: use iov_iter_revert()
sctp: switch to copy_from_iter_full()
net/9p: switch to copy_from_iter_full()
switch memcpy_from_msg() to copy_from_iter_full()
rds: make use of iov_iter_revert()
Fix kdoc parameter spelling from extact to extack.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The patch 3278682123 (make skb_copy_datagram_msg() et.al. preserve
->msg_iter on error) will revert the iov buffer if copy to iter
failed, but it didn't copy any datagram if the skb_checksum_complete
error, so no need to revert any data at this place.
v2: Sabrina notice that return -EFAULT when checksum error is not correct
here, it would confuse the caller about the return value, so fix it.
Fixes: 3278682123 ("make skb_copy_datagram_msg() et.al. preserve->msg_iter on error")
Cc: stable@vger.kernel.org # v4.11
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull block layer updates from Jens Axboe:
- Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
was initially a fork of CFQ, but subsequently changed to implement
fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
to be used on desktop type single drives, providing good fairness.
From Paolo.
- Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
using a scalable token based algorithm that throttles IO based on
live completion IO stats, similary to blk-wbt. From Omar.
- A series from Jan, moving users to separately allocated backing
devices. This continues the work of separating backing device life
times, solving various problems with hot removal.
- A series of updates for lightnvm, mostly from Javier. Includes a
'pblk' target that exposes an open channel SSD as a physical block
device.
- A series of fixes and improvements for nbd from Josef.
- A series from Omar, removing queue sharing between devices on mostly
legacy drivers. This helps us clean up other bits, if we know that a
queue only has a single device backing. This has been overdue for
more than a decade.
- Fixes for the blk-stats, and improvements to unify the stats and user
windows. This both improves blk-wbt, and enables other users to
register a need to receive IO stats for a device. From Omar.
- blk-throttle improvements from Shaohua. This provides a scalable
framework for implementing scalable priotization - particularly for
blk-mq, but applicable to any type of block device. The interface is
marked experimental for now.
- Bucketized IO stats for IO polling from Stephen Bates. This improves
efficiency of polled workloads in the presence of mixed block size
IO.
- A few fixes for opal, from Scott.
- A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
From a variety of folks, mostly Sagi and James Smart.
- A series from Bart, improving our exposed info and capabilities from
the blk-mq debugfs support.
- A series from Christoph, cleaning up how handle WRITE_ZEROES.
- A series from Christoph, cleaning up the block layer handling of how
we track errors in a request. On top of being a nice cleanup, it also
shrinks the size of struct request a bit.
- Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
never used by platforms, and the latter has outlived it's usefulness.
- Various little bug fixes and cleanups from a wide variety of folks.
* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
block: hide badblocks attribute by default
blk-mq: unify hctx delay_work and run_work
block: add kblock_mod_delayed_work_on()
blk-mq: unify hctx delayed_run_work and run_work
nbd: fix use after free on module unload
MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
blk-mq-sched: alloate reserved tags out of normal pool
mtip32xx: use runtime tag to initialize command header
scsi: Implement blk_mq_ops.show_rq()
blk-mq: Add blk_mq_ops.show_rq()
blk-mq: Show operation, cmd_flags and rq_flags names
blk-mq: Make blk_flags_show() callers append a newline character
blk-mq: Move the "state" debugfs attribute one level down
blk-mq: Unregister debugfs attributes earlier
blk-mq: Only unregister hctxs for which registration succeeded
blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
blk-mq: Let blk_mq_debugfs_register() look up the queue name
blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
ide-pm: always pass 0 error to __blk_end_request_all
..
Drivers usually have a number of restrictions for running XDP
- most common being buffer sizes, LRO and number of rings.
Even though some drivers try to be helpful and print error
messages experience shows that users don't often consult
kernel logs on netlink errors. Try to use the new extended
ack mechanism to carry the message back to user space.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
We recently added a check to see if nla_nest_start() fails. There are
two issues with that. First, if it fails then I don't think we should
call nla_nest_cancel(). Second, it's slightly convoluted but the
current code returns success but we should return -EMSGSIZE instead.
Fixes: a50fe0ffd7 ("lwtunnel: check return value of nla_nest_start")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initialise init_net.count to 1 for its pointer from init_nsproxy lest
someone tries to do a get_net() and a put_net() in a process in which
current->ns_proxy->net_ns points to the initial network namespace.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While testing a fix [1] in ___pskb_trim(), addressing the WARN_ON_ONCE()
in skb_try_coalesce() reported by Andrey, I found that we had an skb
with skb->sk set but no skb->destructor.
This invalidated heuristic found in commit 158f323b98 ("net: adjust
skb->truesize in pskb_expand_head()") and in cited patch.
Considering the BUG_ON(skb->sk) we have in skb_orphan(), we should
restrain the temporary setting to a minimal section.
[1] https://patchwork.ozlabs.org/patch/755570/
net: adjust skb->truesize in ___pskb_trim()
Fixes: 8f917bba00 ("bpf: pass sk to helper functions")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey found a way to trigger the WARN_ON_ONCE(delta < len) in
skb_try_coalesce() using syzkaller and a filter attached to a TCP
socket.
As we did recently in commit 158f323b98 ("net: adjust skb->truesize in
pskb_expand_head()") we can adjust skb->truesize from ___pskb_trim(),
via a call to skb_condense().
If all frags were freed, then skb->truesize can be recomputed.
This call can be done if skb is not yet owned, or destructor is
sock_edemux().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix to return error code -EINVAL from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: 622ec2c9d5 ("net: core: add UID to flows, rules, and routes")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since netif_carrier_on() will do nothing if device's carrier is already
on, so it's unnecessary to do carrier status check.
It's the same for netif_carrier_off().
Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Added NULL check to make __dev_kfree_skb_irq consistent with kfree
family of functions.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289
Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This provides a generic SKB based non-optimized XDP path which is used
if either the driver lacks a specific XDP implementation, or the user
requests it via a new IFLA_XDP_FLAGS value named XDP_FLAGS_SKB_MODE.
It is arguable that perhaps I should have required something like
this as part of the initial XDP feature merge.
I believe this is critical for two reasons:
1) Accessibility. More people can play with XDP with less
dependencies. Yes I know we have XDP support in virtio_net, but
that just creates another depedency for learning how to use this
facility.
I wrote this to make life easier for the XDP newbies.
2) As a model for what the expected semantics are. If there is a pure
generic core implementation, it serves as a semantic example for
driver folks adding XDP support.
One thing I have not tried to address here is the issue of
XDP_PACKET_HEADROOM, thanks to Daniel for spotting that. It seems
incredibly expensive to do a skb_cow(skb, XDP_PACKET_HEADROOM) or
whatever even if the XDP program doesn't try to push headers at all.
I think we really need the verifier to somehow propagate whether
certain XDP helpers are used or not.
v5:
- Handle both negative and positive offset after running prog
- Fix mac length in XDP_TX case (Alexei)
- Use rcu_dereference_protected() in free_netdev (kbuild test robot)
v4:
- Fix MAC header adjustmnet before calling prog (David Ahern)
- Disable LRO when generic XDP is installed (Michael Chan)
- Bypass qdisc et al. on XDP_TX and record the event (Alexei)
- Do not perform generic XDP on reinjected packets (DaveM)
v3:
- Make sure XDP program sees packet at MAC header, push back MAC
header if we do XDP_TX. (Alexei)
- Elide GRO when generic XDP is in use. (Alexei)
- Add XDP_FLAG_SKB_MODE flag which the user can use to request generic
XDP even if the driver has an XDP implementation. (Alexei)
- Report whether SKB mode is in use in rtnl_xdp_fill() via XDP_FLAGS
attribute. (Daniel)
v2:
- Add some "fall through" comments in switch statements based
upon feedback from Andrew Lunn
- Use RCU for generic xdp_prog, thanks to Johannes Berg.
Tested-by: Andy Gospodarek <andy@greyhouse.net>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function nla_nest_start() may return a NULL pointer on error. However,
in function lwtunnel_fill_encap(), the return value of nla_nest_start()
is not validated before it is used. This patch checks the return value
of nla_nest_start() against NULL.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for parsing MPLS flows to the flow dissector in preparation for
adding MPLS match support to cls_flower.
Signed-off-by: Benjamin LaHaise <benjamin.lahaise@netronome.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Eric Dumazet <jhs@mojatatu.com>
Cc: Hadar Hen Zion <hadarh@mellanox.com>
Cc: Gao Feng <fgao@ikuai8.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is an e-switch global knob to enable HW support for applying
encapsulation/decapsulation to VF traffic as part of SRIOV e-switch offloading.
The actual encap/decap is carried out (along with the matching and other actions)
per offloaded e-switch rules, e.g as done when offloading the TC tunnel key action.
Signed-off-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Both conflict were simple overlapping changes.
In the kaweth case, Eric Dumazet's skb_cow() bug fix overlapped the
conversion of the driver in net-next to use in-netdev stats.
Signed-off-by: David S. Miller <davem@davemloft.net>
Michal Kubeček