linux-stable.git/net/core/dev.c, branch v4.14.2

tun: call dev_get_valid_name() before register_netdevice()

2017-10-16T20:02:54+00:00

register_netdevice() could fail early when we have an invalid
dev name, in which case ->ndo_uninit() is not called. For tun
device, this is a problem because a timer etc. are already
initialized and it expects ->ndo_uninit() to clean them up.

We could move these initializations into a ->ndo_init() so
that register_netdevice() knows better, however this is still
complicated due to the logic in tun_detach().

Therefore, I choose to just call dev_get_valid_name() before
register_netdevice(), which is quicker and much easier to audit.
And for this specific case, it is already enough.

Fixes: 96442e42429e ("tuntap: choose the txq based on rxq")
Reported-by: Dmitry Alexeev 
Cc: Jason Wang 
Cc: "Michael S. Tsirkin" 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller

net: orphan frags on stand-alone ptype in dev_queue_xmit_nit

2017-09-23T03:31:29+00:00

Zerocopy skbs frags are copied when the skb is looped to a local sock.
Commit 1080e512d44d ("net: orphan frags on receive") introduced calls
to skb_orphan_frags to deliver_skb and __netif_receive_skb for this.

With msg_zerocopy, these skbs can also exist in the tx path and thus
loop from dev_queue_xmit_nit. This already calls deliver_skb in its
loop. But it does not orphan before a separate pt_prev->func().

Add the missing skb_orphan_frags_rx.

Changes
  v1->v2: handle skb_orphan_frags_rx failure

Fixes: 1f8b977ab32d ("sock: enable MSG_ZEROCOPY")
Signed-off-by: Willem de Bruijn 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: change skb->mac_header when Generic XDP calls adjust_head

2017-09-20T22:44:22+00:00

Since XDP's view of the packet includes the MAC header, moving the start-
 of-packet with bpf_xdp_adjust_head needs to also update the offset of the
 MAC header (which is relative to skb->head, not to the skb->data that was
 changed).
Without this, tcpdump sees packets starting from the old MAC header rather
 than the new one, at least in my tests on the loopback device.

Fixes: b5cdae3291f7 ("net: Generic XDP")
Signed-off-by: Edward Cree 
Signed-off-by: David S. Miller

net: rcu lock and preempt disable missing around generic xdp

2017-09-09T04:11:00+00:00

do_xdp_generic must be called inside rcu critical section with preempt
disabled to ensure BPF programs are valid and per-cpu variables used
for redirect operations are consistent. This patch ensures this is true
and fixes the splat below.

The netif_receive_skb_internal() code path is now broken into two rcu
critical sections. I decided it was better to limit the preempt_enable/disable
block to just the xdp static key portion and the fallout is more
rcu_read_lock/unlock calls. Seems like the best option to me.

[  607.596901] =============================
[  607.596906] WARNING: suspicious RCU usage
[  607.596912] 4.13.0-rc4+ #570 Not tainted
[  607.596917] -----------------------------
[  607.596923] net/core/dev.c:3948 suspicious rcu_dereference_check() usage!
[  607.596927]
[  607.596927] other info that might help us debug this:
[  607.596927]
[  607.596933]
[  607.596933] rcu_scheduler_active = 2, debug_locks = 1
[  607.596938] 2 locks held by pool/14624:
[  607.596943]  #0:  (rcu_read_lock_bh){......}, at: [] ip_finish_output2+0x14d/0x890
[  607.596973]  #1:  (rcu_read_lock_bh){......}, at: [] __dev_queue_xmit+0x14a/0xfd0
[  607.597000]
[  607.597000] stack backtrace:
[  607.597006] CPU: 5 PID: 14624 Comm: pool Not tainted 4.13.0-rc4+ #570
[  607.597011] Hardware name: Dell Inc. Precision Tower 5810/0HHV7N, BIOS A17 03/01/2017
[  607.597016] Call Trace:
[  607.597027]  dump_stack+0x67/0x92
[  607.597040]  lockdep_rcu_suspicious+0xdd/0x110
[  607.597054]  do_xdp_generic+0x313/0xa50
[  607.597068]  ? time_hardirqs_on+0x5b/0x150
[  607.597076]  ? mark_held_locks+0x6b/0xc0
[  607.597088]  ? netdev_pick_tx+0x150/0x150
[  607.597117]  netif_rx_internal+0x205/0x3f0
[  607.597127]  ? do_xdp_generic+0xa50/0xa50
[  607.597144]  ? lock_downgrade+0x2b0/0x2b0
[  607.597158]  ? __lock_is_held+0x93/0x100
[  607.597187]  netif_rx+0x119/0x190
[  607.597202]  loopback_xmit+0xfd/0x1b0
[  607.597214]  dev_hard_start_xmit+0x127/0x4e0

Fixes: d445516966dc ("net: xdp: support xdp generic on virtual devices")
Fixes: b5cdae3291f7 ("net: Generic XDP")
Acked-by: Daniel Borkmann 
Signed-off-by: John Fastabend 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-09-02T00:42:05+00:00

Three cases of simple overlapping changes.

Signed-off-by: David S. Miller

mlxsw: spectrum: Forbid linking to devices that have uppers

2017-09-01T16:59:41+00:00

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: 0d65fc13042f ("mlxsw: spectrum: Implement LAG port join/leave")
Signed-off-by: Ido Schimmel 
Reported-by: Nogah Frankel 
Tested-by: Nogah Frankel 
Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller

net: missing call of trace_napi_poll in busy_poll_stop

2017-08-28T18:22:21+00:00

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: Jesper Dangaard Brouer 
Signed-off-by: David S. Miller

xdp: make generic xdp redirect use tracepoint trace_xdp_redirect

2017-08-24T18:59:36+00:00

If the xdp_do_generic_redirect() call fails, it trigger the
trace_xdp_exception tracepoint.  It seems better to use the same
tracepoint trace_xdp_redirect, as the native xdp_do_redirect{,_map} does.

Signed-off-by: Jesper Dangaard Brouer 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

net: export some generic xdp helpers

2017-08-14T02:56:07+00:00

This patch tries to export some generic xdp helpers to drivers. This
can let driver to do XDP for a specific skb. This is useful for the
case when the packet is hard to be processed at page level directly
(e.g jumbo/GSO frame).

With this patch, there's no need for driver to forbid the XDP set when
configuration is not suitable. Instead, it can defer the XDP for
packets that is hard to be processed directly after skb is created.

Signed-off-by: Jason Wang 
Signed-off-by: David S. Miller

net: skb_needs_check() removes CHECKSUM_UNNECESSARY check for tx.

2017-08-11T21:45:52+00:00

Because we remove the UFO support, we will also remove the
CHECKSUM_UNNECESSARY check in skb_needs_check().

Cc: Willem de Bruijn 
Signed-off-by: Tonghao Zhang 
Acked-by: Willem de Bruijn 
Signed-off-by: David S. Miller