This interface uses a temporary buffer, but for no real reason.
And now can generate warnings like:
net/sched/sch_generic.c: In function dev_watchdog
net/sched/sch_generic.c:254:10: warning: unused variable drivername
Just return driver->name directly or "".
Reported-by: Connor Hansen <cmdkhh@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Because there is a possibility that skb is kfree_skb()ed and zero cleared
after ndo_start_xmit, we should not see the contents of skb like skb->len and
skb->dev->name after ndo_start_xmit. But trace_net_dev_xmit does that
and causes panic by NULL pointer dereference.
This patch fixes trace_net_dev_xmit not to see the contents of skb directly.
If you want to reproduce this panic,
1. Get tracepoint of net_dev_xmit on
2. Create 2 guests on KVM
2. Make 2 guests use virtio_net
4. Execute netperf from one to another for a long time as a network burden
5. host will panic(It takes about 30 minutes)
Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the device passed into dev_disable_lro is a vlan, then repoint the dev
poniter so that we actually modify the underlying physical device.
Signed-of-by: Neil Horman <nhorman@tuxdriver.com>
CC: davem@davemloft.net
CC: bhutchings@solarflare.com
Signed-off-by: David S. Miller <davem@davemloft.net>
synchronize_rcu() is very slow in various situations (HZ=100,
CONFIG_NO_HZ=y, CONFIG_PREEMPT=n)
Extract from my (mostly idle) 8 core machine :
synchronize_rcu() in 99985 us
synchronize_rcu() in 79982 us
synchronize_rcu() in 87612 us
synchronize_rcu() in 79827 us
synchronize_rcu() in 109860 us
synchronize_rcu() in 98039 us
synchronize_rcu() in 89841 us
synchronize_rcu() in 79842 us
synchronize_rcu() in 80151 us
synchronize_rcu() in 119833 us
synchronize_rcu() in 99858 us
synchronize_rcu() in 73999 us
synchronize_rcu() in 79855 us
synchronize_rcu() in 79853 us
When we hold RTNL mutex, we would like to spend some cpu cycles but not
block too long other processes waiting for this mutex.
We also want to setup/dismantle network features as fast as possible at
boot/shutdown time.
This patch makes synchronize_net() call the expedited version if RTNL is
locked.
synchronize_rcu_expedited() typical delay is about 20 us on my machine.
synchronize_rcu_expedited() in 18 us
synchronize_rcu_expedited() in 18 us
synchronize_rcu_expedited() in 18 us
synchronize_rcu_expedited() in 18 us
synchronize_rcu_expedited() in 20 us
synchronize_rcu_expedited() in 16 us
synchronize_rcu_expedited() in 20 us
synchronize_rcu_expedited() in 18 us
synchronize_rcu_expedited() in 18 us
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
CC: Ben Greear <greearb@candelatech.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the old days, we used to access dev->master in __netif_receive_skb()
in a rcu_read_lock section.
So one synchronize_net() call was needed in netdev_set_master() to make
sure another cpu could not use old master while/after we release it.
We now use netdev_rx_handler infrastructure and added one
synchronize_net() call in bond_release()/bond_release_all()
Remove the obsolete synchronize_net() from netdev_set_master() and add
one in bridge del_nbp() after its netdev_rx_handler_unregister() call.
This makes enslave -d a bit faster.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Jiri Pirko <jpirko@redhat.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When one macvlan device is dismantled, we can avoid one
synchronize_rcu() call done after deletion from hash list, since caller
will perform a synchronize_net() call after its ndo_stop() call.
Add a new netdev->dismantle field to signal this dismantle intent.
Reduces RTNL hold time.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
CC: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cool, how about we make 'Features changed' debug as well?
This way userspace can't fill up the log just by tweaking tun features
with an ioctl.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using plain hlist_del() in dev_change_name() is wrong since a
concurrent reader can crash trying to dereference LIST_POISON1.
Bug introduced in commit 72c9528bab (net: Introduce
dev_get_by_name_rcu())
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Those reduced to DEBUG can possibly be triggered by unprivileged processes
and are nothing exceptional. Illegal checksum combinations can only be
caused by driver bug, so promote those messages to WARN.
Since GSO without SG will now only cause DEBUG message from
netdev_fix_features(), remove the workaround from register_netdevice().
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
It will be needed by bonding and other drivers changing vlan_features
after ndo_init callback.
As a bonus, this includes kernel-doc for netdev_update_features().
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 443457242b (factorize sync-rcu call in
unregister_netdevice_many) mistakenly removed one test from dev_close()
Following actions trigger a BUG :
modprobe bonding
modprobe dummy
ifconfig bond0 up
ifenslave bond0 dummy0
rmmod dummy
dev_close() must not close a non IFF_UP device.
With help from Frank Blaschka and Einar EL Lueck
Reported-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Reported-by: Einar EL Lueck <ELELUECK@de.ibm.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Force dev_alloc_name() to be called from register_netdevice() by
dev_get_valid_name(). That allows to remove multiple explicit
dev_alloc_name() calls.
The possibility to call dev_alloc_name in advance remains.
This also fixes veth creation regresion caused by
84c49d8c3e
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ioctl() calls against a socket with an inappropriate ioctl operation
are incorrectly returning EINVAL rather than ENOTTY:
[ENOTTY]
Inappropriate I/O control operation.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=33992
Signed-off-by: Lifeng Sun <lifongsun@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes sure that when a driver calls the ethtool's
get/set_settings() callback of another driver, the data passed to it
is clean. This guarantees that speed_hi will be zeroed correctly if
the called callback doesn't explicitely set it: we are sure we don't
get a corrupted speed from the underlying driver. We also take care of
setting the cmd field appropriately (ETHTOOL_GSET/SSET).
This applies to dev_ethtool_get_settings(), which now makes sure it
sets up that ethtool command parameter correctly before passing it to
drivers. This also means that whoever calls dev_ethtool_get_settings()
does not have to clean the ethtool command parameter. This function
also becomes an exported symbol instead of an inline.
All drivers visible to make allyesconfig under x86_64 have been
updated.
Signed-off-by: David Decotigny <decot@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simplify and fix netdev_increment_features() to conform to what is
stated in netdevice.h comments about NETIF_F_ONE_FOR_ALL.
Include FCoE segmentation and VLAN-challedged flags in computation.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since now when bonding uses rx_handler, all traffic going into bond
device goes thru bond_handle_frame. So there's no need to go back into
bonding code later via ptype handlers. This patch converts
original ptype handlers into "bonding receive probes". These functions
are called from bond_handle_frame and they are registered per-mode.
Note that vlan packets are also handled because they are always untagged
thanks to vlan_untag()
Note that this also allows arpmon for eth-bond-bridge-vlan topology.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
NETIF_F_TSO_ECN has no effect when TSO is disabled; this just means
that feature state will be accurately reported to user-space.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The feature flags NETIF_F_TSO and NETIF_F_TSO6 independently enable
TSO for IPv4 and IPv6 respectively. However, the test in
netdev_fix_features() and its predecessor functions was never updated
to check for NETIF_F_TSO6, possibly because it was originally proposed
that TSO for IPv6 would be dependent on both feature flags.
Now that these feature flags can be changed independently from
user-space and we depend on netdev_fix_features() to fix invalid
feature combinations, it's important to disable them both if
scatter-gather is disabled. Also disable NETIF_F_TSO_ECN so
user-space sees all TSO features as disabled.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now there are 2 paths for rx vlan frames. When rx-vlan-hw-accel is
enabled, skb is untagged by NIC, vlan_tci is set and the skb gets into
vlan code in __netif_receive_skb - vlan_hwaccel_do_receive.
For non-rx-vlan-hw-accel however, tagged skb goes thru whole
__netif_receive_skb, it's untagged in ptype_base hander and reinjected
This incosistency is fixed by this patch. Vlan untagging happens early in
__netif_receive_skb so the rest of code (ptype_all handlers, rx_handlers)
see the skb like it was untagged by hw.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
v1->v2:
remove "inline" from vlan_core.c functions
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch uses __copy_from_user_nocache on transmit to bypass data
cache for a performance improvement. skb_add_data_nocache and
skb_copy_to_page_nocache can be called by sendmsg functions to use
this feature, initial support is in tcp_sendmsg. This functionality is
configurable per device using ethtool.
Presumably, this feature would only be useful when the driver does
not touch the data. The feature is turned on by default if a device
indicates that it does some form of checksum offload; it is off by
default for devices that do no checksum offload or indicate no checksum
is necessary. For the former case copy-checksum is probably done
anyway, in the latter case the device is likely loopback in which case
the no cache copy is probably not beneficial.
This patch was tested using 200 instances of netperf TCP_RR with
1400 byte request and one byte reply. Platform is 16 core AMD x86.
No-cache copy disabled:
672703 tps, 97.13% utilization
50/90/99% latency:244.31 484.205 1028.41
No-cache copy enabled:
702113 tps, 96.16% utilization,
50/90/99% latency 238.56 467.56 956.955
Using 14000 byte request and response sizes demonstrate the
effects more dramatically:
No-cache copy disabled:
79571 tps, 34.34 %utlization
50/90/95% latency 1584.46 2319.59 5001.76
No-cache copy enabled:
83856 tps, 34.81% utilization
50/90/95% latency 2508.42 2622.62 2735.88
Note especially the effect on latency tail (95th percentile).
This seems to provide a nice performance improvement and is
consistent in the tests I ran. Presumably, this would provide
the greatest benfits in the presence of an application workload
stressing the cache and a lot of transmit data happening.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Issue FEAT_CHANGE notification when features are changed by
netdev_update_features(). This will allow changes made by extra constraints
on e.g. MTU change to be properly propagated like changes via ethtool.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case the device where is coming from the packet has TSO enabled,
we should not check the mtu size value as this one could be bigger
than the expected value.
This is the case for the macvlan driver when the lower device has
TSO enabled. The macvlan inherit this feature and forward the packets
without fragmenting them. Then the packets go through dev_forward_skb
and are dropped. This patch fix this by checking TSO is not enabled
when we want to check the mtu size.
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The mac address of the bridge device may be changed when a new interface
is added to the bridge. If this happens, then the bridge needs to call
the network notifiers to tickle any other systems that care. Since bridge
can be a module, this also means exporting the notifier function.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code itself can explain what it is doing, no need these comments.
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement compatibility with new hw_features for dev_disable_lro().
This is a transition path - dev_disable_lro() should be later
integrated into netdev_fix_features() after all drivers are converted.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows rx_handlers to better signalize what to do next to
it's caller. That makes skb->deliver_no_wcard no longer needed.
kernel-doc for rx_handler_result is taken from Nicolas' patch.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reviewed-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since a8f80e8ff9 any process with
CAP_NET_ADMIN may load any module from /lib/modules/. This doesn't mean
that CAP_NET_ADMIN is a superset of CAP_SYS_MODULE as modules are
limited to /lib/modules/**. However, CAP_NET_ADMIN capability shouldn't
allow anybody load any module not related to networking.
This patch restricts an ability of autoloading modules to netdev modules
with explicit aliases. This fixes CVE-2011-1019.
Arnd Bergmann suggested to leave untouched the old pre-v2.6.32 behavior
of loading netdev modules by name (without any prefix) for processes
with CAP_SYS_MODULE to maintain the compatibility with network scripts
that use autoloading netdev modules by aliases like "eth0", "wlan0".
Currently there are only three users of the feature in the upstream
kernel: ipip, ip_gre and sit.
root@albatros:~# capsh --drop=$(seq -s, 0 11),$(seq -s, 13 34) --
root@albatros:~# grep Cap /proc/$$/status
CapInh: 0000000000000000
CapPrm: fffffff800001000
CapEff: fffffff800001000
CapBnd: fffffff800001000
root@albatros:~# modprobe xfs
FATAL: Error inserting xfs
(/lib/modules/2.6.38-rc6-00001-g2bf4ca3/kernel/fs/xfs/xfs.ko): Operation not permitted
root@albatros:~# lsmod | grep xfs
root@albatros:~# ifconfig xfs
xfs: error fetching interface information: Device not found
root@albatros:~# lsmod | grep xfs
root@albatros:~# lsmod | grep sit
root@albatros:~# ifconfig sit
sit: error fetching interface information: Device not found
root@albatros:~# lsmod | grep sit
root@albatros:~# ifconfig sit0
sit0 Link encap:IPv6-in-IPv4
NOARP MTU:1480 Metric:1
root@albatros:~# lsmod | grep sit
sit 10457 0
tunnel4 2957 1 sit
For CAP_SYS_MODULE module loading is still relaxed:
root@albatros:~# grep Cap /proc/$$/status
CapInh: 0000000000000000
CapPrm: ffffffffffffffff
CapEff: ffffffffffffffff
CapBnd: ffffffffffffffff
root@albatros:~# ifconfig xfs
xfs: error fetching interface information: Device not found
root@albatros:~# lsmod | grep xfs
xfs 745319 0
Reference: https://lkml.org/lkml/2011/2/24/203
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Kees Cook <kees.cook@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
This was there before, I forgot about this. Allows deliveries to
ptype_base handlers registered for orig_dev. I presume this is still
desired.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reviewed-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid "Features changed" message and ndo_set_features call on device
registration caused by automatic enabling of GSO and GRO. Driver should
have enabled hardware offloads it set in features, so the ndo_set_features()
is not needed at registration time.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix netdev_update_features() messages on register time by moving
the call further in register_netdevice(). When
netdev->reg_state != NETREG_REGISTERED, netdev_name() returns
"(unregistered netdevice)" even if the dev's name is already filled.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 9b5e383c11 (net: Introduce
unregister_netdevice_many()) left an active LIST_HEAD() in
rollback_registered(), with possible memory corruption.
Even if device is freed without touching its unreg_list (and therefore
touching the previous memory location holding LISTE_HEAD(single), better
close the bug for good, since its really subtle.
(Same fix for default_device_exit_batch() for completeness)
Reported-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Michal Hocko <mhocko@suse.cz>
Reported-by: Eric W. Biderman <ebiderman@xmission.com>
Tested-by: Eric W. Biderman <ebiderman@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Octavian Purdila <opurdila@ixiacom.com>
CC: stable <stable@kernel.org> [.33+]
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric W. Biderman and Michal Hocko reported various memory corruptions
that we suspected to be related to a LIST head located on stack, that
was manipulated after thread left function frame (and eventually exited,
so its stack was freed and reused).
Eric Dumazet suggested the problem was probably coming from commit
443457242b (net: factorize
sync-rcu call in unregister_netdevice_many)
This patch fixes __dev_close() and dev_close() to properly deinit their
respective LIST_HEAD(single) before exiting.
References: https://lkml.org/lkml/2011/2/16/304
References: https://lkml.org/lkml/2011/2/14/223
Reported-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Michal Hocko <mhocko@suse.cz>
Reported-by: Eric W. Biderman <ebiderman@xmission.com>
Tested-by: Eric W. Biderman <ebiderman@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This introduces a new framework to handle device features setting.
It consists of:
- new fields in struct net_device:
+ hw_features - features that hw/driver supports toggling
+ wanted_features - features that user wants enabled, when possible
- new netdev_ops:
+ feat = ndo_fix_features(dev, feat) - API checking constraints for
enabling features or their combinations
+ ndo_set_features(dev) - API updating hardware state to match
changed dev->features
- new ethtool commands:
+ ETHTOOL_GFEATURES/ETHTOOL_SFEATURES: get/set dev->wanted_features
and trigger device reconfiguration if resulting dev->features
changed
+ ETHTOOL_GSTRINGS(ETH_SS_FEATURES): get feature bits names (meaning)
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
For testing and debugging purposes it is useful to be able to disable
hardware acceleration of RFS without disabling RFS altogether. Since
this is a similar feature to 'n-tuple' flow steering through the
ethtool API, test the same feature flag that controls that.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>