When writing packets to a descriptor associated with a combined queue, the
packets should end up on that queue.
Before this change all packets written to any descriptor associated with a
tap interface end up on rx-0, even when the descriptor is associated with a
different queue.
The rx traffic can be generated by either of the following.
1. a simple tap program which spins up multiple queues and writes packets
to each of the file descriptors
2. tx from a qemu vm with a tap multiqueue netdev
The queue for rx traffic can be observed by either of the following (done
on the hypervisor in the qemu case).
1. a simple netmap program which opens and reads from per-queue
descriptors
2. configuring RPS and doing per-cpu captures with rxtxcpu
Alternatively, if you printk() the return value of skb_get_rx_queue() just
before each instance of netif_receive_skb() in tun.c, you will get 65535
for every skb.
Calling skb_record_rx_queue() to set the rx queue to the queue_index fixes
the association between descriptor and rx queue.
Signed-off-by: Matthew Cover <matthew.cover@stackpath.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Configuring generic network device parameters on tun will fail in
presence of IFLA_INFO_KIND attribute in IFLA_LINKINFO nested attribute
since tun_validate() always return failure.
This can be visualized with following ip-link(8) command sequences:
# ip link set dev tun0 group 100
# ip link set dev tun0 group 100 type tun
RTNETLINK answers: Invalid argument
with contrast to dummy and veth drivers:
# ip link set dev dummy0 group 100
# ip link set dev dummy0 type dummy
# ip link set dev veth0 group 100
# ip link set dev veth0 group 100 type veth
Fix by returning zero in tun_validate() when @data is NULL that is
always in case since rtnl_link_ops->maxtype is zero in tun driver.
Fixes: f019a7a594 ("tun: Implement ip link del tunXXX")
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Because the function __skb_get_hash_symmetric always returns non-zero.
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Wang Li <wangli39@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net'
overlapped the renaming of a netlink attribute in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
tun_napi_disable() and tun_napi_del() do not need
a pointer to the tun_struct
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Version bump conflict in batman-adv, take what's in net-next.
iavf conflict, adjustment of netdev_ops in net-next conflicting
with poll controller method removal in net.
Signed-off-by: David S. Miller <davem@davemloft.net>
As diagnosed by Song Liu, ndo_poll_controller() can
be very dangerous on loaded hosts, since the cpu
calling ndo_poll_controller() might steal all NAPI
contexts (for all RX/TX queues of the NIC). This capture
can last for unlimited amount of time, since one
cpu is generally not able to drain all the queues under load.
tun uses NAPI for TX completions, so we better let core
networking stack call the napi->poll() to avoid the capture.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implement TUN_MSG_PTR msg_control type. This type allows
the caller to pass an array of XDP buffs to tuntap through ptr field
of the tun_msg_control. If an XDP program is attached, tuntap can run
XDP program directly. If not, tuntap will build skb and do a fast
receiving since part of the work has been done by vhost_net.
This will avoid lots of indirect calls thus improves the icache
utilization and allows to do XDP batched flushing when doing XDP
redirection.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces to a new tun/tap specific msg_control:
#define TUN_MSG_UBUF 1
#define TUN_MSG_PTR 2
struct tun_msg_ctl {
int type;
void *ptr;
};
This allows us to pass different kinds of msg_control through
sendmsg(). The first supported type is ubuf (TUN_MSG_UBUF) which will
be used by the existed vhost_net zerocopy code. The second is XDP
buff, which allows vhost_net to pass XDP buff to TUN. This could be
used to implement accepting an array of XDP buffs from vhost_net in
the following patches.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch split out XDP logic into a single function. This make it to
be reused by XDP batching path in the following patch.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we're sure not to go native XDP, there's no need for several things
like bh and rcu stuffs. So this patch introduces a helper to build skb
and hold page refcnt. When we found we will go through skb path, build
skb directly.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's no need to duplicate page get logic in each action. So this
patch tries to get page and calculate the offset before processing XDP
actions (except for XDP_DROP), and undo them when meet errors (we
don't care the performance on errors). This will be used for factoring
out XDP logic.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch move the bh enabling a little bit earlier, this will be
used for factoring out the core XDP logic of tuntap.
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces a new sock flag - SOCK_XDP. This will be used
for notifying the upper layer that XDP program is attached on the
lower socket, and requires for extra headroom.
TUN will be the first user.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull core signal handling updates from Eric Biederman:
"It was observed that a periodic timer in combination with a
sufficiently expensive fork could prevent fork from every completing.
This contains the changes to remove the need for that restart.
This set of changes is split into several parts:
- The first part makes PIDTYPE_TGID a proper pid type instead
something only for very special cases. The part starts using
PIDTYPE_TGID enough so that in __send_signal where signals are
actually delivered we know if the signal is being sent to a a group
of processes or just a single process.
- With that prep work out of the way the logic in fork is modified so
that fork logically makes signals received while it is running
appear to be received after the fork completes"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits)
signal: Don't send signals to tasks that don't exist
signal: Don't restart fork when signals come in.
fork: Have new threads join on-going signal group stops
fork: Skip setting TIF_SIGPENDING in ptrace_init_task
signal: Add calculate_sigpending()
fork: Unconditionally exit if a fatal signal is pending
fork: Move and describe why the code examines PIDNS_ADDING
signal: Push pid type down into complete_signal.
signal: Push pid type down into __send_signal
signal: Push pid type down into send_signal
signal: Pass pid type into do_send_sig_info
signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task
signal: Pass pid type into group_send_sig_info
signal: Pass pid and pid type into send_sigqueue
posix-timers: Noralize good_sigevent
signal: Use PIDTYPE_TGID to clearly store where file signals will be sent
pid: Implement PIDTYPE_TGID
pids: Move the pgrp and session pid pointers from task_struct to signal_struct
kvm: Don't open code task_pid in kvm_vcpu_ioctl
pids: Compute task_tgid using signal->leader_pid
...
0x3ff in tun_hashfn is mask of TUN_NUM_FLOW_ENTRIES, instead
of hardcode, define a macro to setup the relationship with
TUN_NUM_FLOW_ENTRIES
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When f_setown is called a pid and a pid type are stored. Replace the use
of PIDTYPE_PID with PIDTYPE_TGID as PIDTYPE_TGID goes to the entire thread
group. Replace the use of PIDTYPE_MAX with PIDTYPE_PID as PIDTYPE_PID now
is only for a thread.
Update the users of __f_setown to use PIDTYPE_TGID instead of
PIDTYPE_PID.
For now the code continues to capture task_pid (when task_tgid would
really be appropriate), and iterate on PIDTYPE_PID (even when type ==
PIDTYPE_TGID) out of an abundance of caution to preserve existing
behavior.
Oleg Nesterov suggested using the test to ensure we use PIDTYPE_PID
for tgid lookup also be used to avoid taking the tasklist lock.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
On XDP_TX we need to free up the frame only when tun_xdp_tx() returns a
negative value. A positive value indicates that the packet is
successfully enqueued to the ptr_ring, so freeing the page causes
use-after-free.
Fixes: 735fc4054b ("xdp: change ndo_xdp_xmit API to support bulking")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-07-15
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Various different arm32 JIT improvements in order to optimize code emission
and make the JIT code itself more robust, from Russell.
2) Support simultaneous driver and offloaded XDP in order to allow for advanced
use-cases where some work is offloaded to the NIC and some to the host. Also
add ability for bpftool to load programs and maps beyond just the cgroup case,
from Jakub.
3) Add BPF JIT support in nfp for multiplication as well as division. For the
latter in particular, it uses the reciprocal algorithm to emulate it, from Jiong.
4) Add BTF pretty print functionality to bpftool in plain and JSON output
format, from Okash.
5) Add build and installation to the BPF helper man page into bpftool, from Quentin.
6) Add a TCP BPF callback for listening sockets which is triggered right after
the socket transitions to TCP_LISTEN state, from Andrey.
7) Add a new cgroup tree command to bpftool which iterates over the whole cgroup
tree and prints all attached programs, from Roman.
8) Improve xdp_redirect_cpu sample to support parsing of double VLAN tagged
packets, from Jesper.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
prog_attached of struct netdev_bpf should have been superseded
by simply setting prog_id long time ago, but we kept it around
to allow offloading drivers to communicate attachment mode (drv
vs hw). Subsequently drivers were also allowed to report back
attachment flags (prog_flags), and since nowadays only programs
attached will XDP_FLAGS_HW_MODE can get offloaded, we can tell
the attachment mode from the flags driver reports. Remove
prog_attached member.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch makes it so that instead of passing a void pointer as the
accel_priv we instead pass a net_device pointer as sb_dev. Making this
change allows us to pass the subordinate device through to the fallback
function eventually so that we can keep the actual code in the
ndo_select_queue call as focused on possible on the exception cases.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Tun, tap, virtio, packet and uml vector all use struct virtio_net_hdr
to communicate packet metadata to userspace.
For skbuffs with vlan, the first two return the packet as it may have
existed on the wire, inserting the VLAN tag in the user buffer. Then
virtio_net_hdr.csum_start needs to be adjusted by VLAN_HLEN bytes.
Commit f09e2249c4 ("macvtap: restore vlan header on user read")
added this feature to macvtap. Commit 3ce9b20f19 ("macvtap: Fix
csum_start when VLAN tags are present") then fixed up csum_start.
Virtio, packet and uml do not insert the vlan header in the user
buffer.
When introducing virtio_net_hdr_from_skb to deduplicate filling in
the virtio_net_hdr, the variant from macvtap which adds VLAN_HLEN was
applied uniformly, breaking csum offset for packets with vlan on
virtio and packet.
Make insertion of VLAN_HLEN optional. Convert the callers to pass it
when needed.
Fixes: e858fae2b0 ("virtio_net: use common code for virtio_net_hdr and skb GSO conversion")
Fixes: 1276f24eee ("packet: use common code for virtio_net_hdr and skb GSO conversion")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-06-05
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Add a new BPF hook for sendmsg similar to existing hooks for bind and
connect: "This allows to override source IP (including the case when it's
set via cmsg(3)) and destination IP:port for unconnected UDP (slow path).
TCP and connected UDP (fast path) are not affected. This makes UDP support
complete, that is, connected UDP is handled by connect hooks, unconnected
by sendmsg ones.", from Andrey.
2) Rework of the AF_XDP API to allow extending it in future for type writer
model if necessary. In this mode a memory window is passed to hardware
and multiple frames might be filled into that window instead of just one
that is the case in the current fixed frame-size model. With the new
changes made this can be supported without having to add a new descriptor
format. Also, core bits for the zero-copy support for AF_XDP have been
merged as agreed upon, where i40e bits will be routed via Jeff later on.
Various improvements to documentation and sample programs included as
well, all from Björn and Magnus.
3) Given BPF's flexibility, a new program type has been added to implement
infrared decoders. Quote: "The kernel IR decoders support the most
widely used IR protocols, but there are many protocols which are not
supported. [...] There is a 'long tail' of unsupported IR protocols,
for which lircd is need to decode the IR. IR encoding is done in such
a way that some simple circuit can decode it; therefore, BPF is ideal.
[...] user-space can define a decoder in BPF, attach it to the rc
device through the lirc chardev.", from Sean.
4) Several improvements and fixes to BPF core, among others, dumping map
and prog IDs into fdinfo which is a straight forward way to correlate
BPF objects used by applications, removing an indirect call and therefore
retpoline in all map lookup/update/delete calls by invoking the callback
directly for 64 bit archs, adding a new bpf_skb_cgroup_id() BPF helper
for tc BPF programs to have an efficient way of looking up cgroup v2 id
for policy or other use cases. Fixes to make sure we zero tunnel/xfrm
state that hasn't been filled, to allow context access wrt pt_regs in
32 bit archs for tracing, and last but not least various test cases
for fixes that landed in bpf earlier, from Daniel.
5) Get rid of the ndo_xdp_flush API and extend the ndo_xdp_xmit with
a XDP_XMIT_FLUSH flag instead which allows to avoid one indirect
call as flushing is now merged directly into ndo_xdp_xmit(), from Jesper.
6) Add a new bpf_get_current_cgroup_id() helper that can be used in
tracing to retrieve the cgroup id from the current process in order
to allow for e.g. aggregation of container-level events, from Yonghong.
7) Two follow-up fixes for BTF to reject invalid input values and
related to that also two test cases for BPF kselftests, from Martin.
8) Various API improvements to the bpf_fib_lookup() helper, that is,
dropping MPLS bits which are not fully hashed out yet, rejecting
invalid helper flags, returning error for unsupported address
families as well as renaming flowlabel to flowinfo, from David.
9) Various fixes and improvements to sockmap BPF kselftests in particular
in proper error detection and data verification, from Prashant.
10) Two arm32 BPF JIT improvements. One is to fix imm range check with
regards to whether immediate fits into 24 bits, and a naming cleanup
to get functions related to rsh handling consistent to those handling
lsh, from Wang.
11) Two compile warning fixes in BPF, one for BTF and a false positive
to silent gcc in stack_map_get_build_id_offset(), from Arnd.
12) Add missing seg6.h header into tools include infrastructure in order
to fix compilation of BPF kselftests, from Mathieu.
13) Several formatting cleanups in the BPF UAPI helper description that
also fix an error during rst2man compilation, from Quentin.
14) Hide an unused variable in sk_msg_convert_ctx_access() when IPv6 is
not built into the kernel, from Yue.
15) Remove a useless double assignment in dev_map_enqueue(), from Colin.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the ndo_xdp_flush call implementation tun_xdp_flush
as no callers of ndo_xdp_flush are left.
The tun drivers XDP_TX implementation also used tun_xdp_flush (and
tun_xdp_xmit). This is easily solved by passing the XDP_XMIT_FLUSH
flag to tun_xdp_xmit in tun_xdp_tx.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Let user space set whatever it would like to advertise for the
tun interface. Preserve the existing defaults.
Signed-off-by: Chas Williams <3chas3@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When passed the XDP_XMIT_FLUSH flag tun_xdp_xmit now performs the same
kind of socket wake up as in tun_xdp_flush(). The wake up code from
tun_xdp_flush is generalized and shared with tun_xdp_xmit.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch only change the API and reject any use of flags. This is an
intermediate step that allows us to implement the flush flag operation
later, for each individual driver in a separate patch.
The plan is to implement flush operation via XDP_XMIT_FLUSH flag
and then remove XDP_XMIT_FLAGS_NONE when done.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Filling in the padding slot in the bpf structure as a bug fix in 'ne'
overlapped with actually using that padding area for something in
'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2018-05-24
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Björn Töpel cleans up AF_XDP (removes rebind, explicit cache alignment from uapi, etc).
2) David Ahern adds mtu checks to bpf_ipv{4,6}_fib_lookup() helpers.
3) Jesper Dangaard Brouer adds bulking support to ndo_xdp_xmit.
4) Jiong Wang adds support for indirect and arithmetic shifts to NFP
5) Martin KaFai Lau cleans up BTF uapi and makes the btf_header extensible.
6) Mathieu Xhonneux adds an End.BPF action to seg6local with BPF helpers allowing
to edit/grow/shrink a SRH and apply on a packet generic SRv6 actions.
7) Sandipan Das adds support for bpf2bpf function calls in ppc64 JIT.
8) Yonghong Song adds BPF_TASK_FD_QUERY command for introspection of tracing events.
9) other misc fixes from Gustavo A. R. Silva, Sirio Balmelli, John Fastabend, and Magnus Karlsson
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch change the API for ndo_xdp_xmit to support bulking
xdp_frames.
When kernel is compiled with CONFIG_RETPOLINE, XDP sees a huge slowdown.
Most of the slowdown is caused by DMA API indirect function calls, but
also the net_device->ndo_xdp_xmit() call.
Benchmarked patch with CONFIG_RETPOLINE, using xdp_redirect_map with
single flow/core test (CPU E5-1650 v4 @ 3.60GHz), showed
performance improved:
for driver ixgbe: 6,042,682 pps -> 6,853,768 pps = +811,086 pps
for driver i40e : 6,187,169 pps -> 6,724,519 pps = +537,350 pps
With frames avail as a bulk inside the driver ndo_xdp_xmit call,
further optimizations are possible, like bulk DMA-mapping for TX.
Testing without CONFIG_RETPOLINE show the same performance for
physical NIC drivers.
The virtual NIC driver tun sees a huge performance boost, as it can
avoid doing per frame producer locking, but instead amortize the
locking cost over the bulk.
V2: Fix compile errors reported by kbuild test robot <lkp@intel.com>
V4: Isolated ndo, driver changes and callers.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When link is down, writes to the device might fail with
-EIO. Userspace needs an indication when the status is resolved. As a
fix, tun_net_open() attempts to wake up writers - but that is only
effective if SOCKWQ_ASYNC_NOSPACE has been set in the past. This is
not the case of vhost_net which only poll for EPOLLOUT after it meets
errors during sendmsg().
This patch fixes this by making sure SOCKWQ_ASYNC_NOSPACE is set when
socket is not writable or device is down to guarantee EPOLLOUT will be
raised in either tun_chr_poll() or tun_sock_write_space() after device
is up.
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Eric Dumazet <edumazet@google.com>
Fixes: 1bd4978a88 ("tun: honor IFF_UP in tun_get_user()")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
S390 bpf_jit.S is removed in net-next and had changes in 'net',
since that code isn't used any more take the removal.
TLS data structures split the TX and RX components in 'net-next',
put the new struct members from the bug fix in 'net' into the RX
part.
The 'net-next' tree had some reworking of how the ERSPAN code works in
the GRE tunneling code, overlapping with a one-line headroom
calculation fix in 'net'.
Overlapping changes in __sock_map_ctx_update_elem(), keep the bits
that read the prog members via READ_ONCE() into local variables
before using them.
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit b196d88aba ("tun: fix use after free for ptr_ring") we
need clean up tx ring during release(). But unfortunately, it tries to
do the cleanup blindly after socket were destroyed which will lead
another use-after-free. Fix this by doing the cleanup before dropping
the last reference of the socket in __tun_detach().
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Fixes: b196d88aba ("tun: fix use after free for ptr_ring")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We used to initialize ptr_ring during TUNSETIFF, this is because its
size depends on the tx_queue_len of netdevice. And we try to clean it
up when socket were detached from netdevice. A race were spotted when
trying to do uninit during a read which will lead a use after free for
pointer ring. Solving this by always initialize a zero size ptr_ring
in open() and do resizing during TUNSETIFF, and then we can safely do
cleanup during close(). With this, there's no need for the workaround
that was introduced by commit 4df0bfc799 ("tun: fix a memory leak
for tfile->tx_array").
Reported-by: syzbot+e8b902c3c3fadf0a9dba@syzkaller.appspotmail.com
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Fixes: 1576d98605 ("tun: switch to use skb array for tx")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since net ns of tun device is assigned on the device creation,
and it never changes, we do not need to use any lock to get it
from alive tun.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-04-21
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Initial work on BPF Type Format (BTF) is added, which is a meta
data format which describes the data types of BPF programs / maps.
BTF has its roots from CTF (Compact C-Type format) with a number
of changes to it. First use case is to provide a generic pretty
print capability for BPF maps inspection, later work will also
add BTF to bpftool. pahole support to convert dwarf to BTF will
be upstreamed as well (https://github.com/iamkafai/pahole/tree/btf),
from Martin.
2) Add a new xdp_bpf_adjust_tail() BPF helper for XDP that allows
for changing the data_end pointer. Only shrinking is currently
supported which helps for crafting ICMP control messages. Minor
changes in drivers have been added where needed so they recalc
the packet's length also when data_end was adjusted, from Nikita.
3) Improve bpftool to make it easier to feed hex bytes via cmdline
for map operations, from Quentin.
4) Add support for various missing BPF prog types and attach types
that have been added to kernel recently but neither to bpftool
nor libbpf yet. Doc and bash completion updates have been added
as well for bpftool, from Andrey.
5) Proper fix for avoiding to leak info stored in frame data on page
reuse for the two bpf_xdp_adjust_{head,meta} helpers by disallowing
to move the pointers into struct xdp_frame area, from Jesper.
6) Follow-up compile fix from BTF in order to include stdbool.h in
libbpf, from Björn.
7) Few fixes in BPF sample code, that is, a typo on the netdevice
in a comment and fixup proper dump of XDP action code in the
tracepoint exception, from Wang and Jesper.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the tun driver, in absence of an eBPF steering program,
always compute the rxhash in its rx path, even when such value
is later unused due to additional checks (
This changeset moves the all the related checks just before the
__skb_get_hash_symmetric(), so that the latter is no more computed
when unneeded.
Also replace an unneeded RCU section with rcu_access_pointer().
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for tun driver we need to adjust XDP_PASS handling by recalculating
length of the packet if it was passed to the TCP/IP stack
(in case if after xdp's prog run data_end pointer was adjusted)
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Bogus trimming in tun_net_xmit() causes truncated vlan packets.
skb->len is correct whether or not skb_vlan_tag_present() is true. There
is no more reason to adjust the skb length on xmit in this driver than
any other driver. tun_put_user() adds 4 bytes to the total for tagged
packets because it transmits the tag inline to userspace. This is
similar to a nic transmitting the tag inline on the wire.
Reproducing the bug by sending any tagged packet through back-to-back
connected tap interfaces:
socat TUN,tun-type=tap,iff-up,tun-name=in TUN,tun-type=tap,iff-up,tun-name=out &
ip link add link in name in.20 type vlan id 20
ip addr add 10.9.9.9/24 dev in.20
ip link set in.20 up
tshark -nxxi in -f arp -c1 2>/dev/null &
tshark -nxxi out -f arp -c1 2>/dev/null &
ping -c 1 10.9.9.5 >/dev/null 2>&1
The output from the 'in' and 'out' interfaces are different when the
bug is present:
Capturing on 'in'
0000 ff ff ff ff ff ff 76 cf 76 37 d5 0a 81 00 00 14 ......v.v7......
0010 08 06 00 01 08 00 06 04 00 01 76 cf 76 37 d5 0a ..........v.v7..
0020 0a 09 09 09 00 00 00 00 00 00 0a 09 09 05 ..............
Capturing on 'out'
0000 ff ff ff ff ff ff 76 cf 76 37 d5 0a 81 00 00 14 ......v.v7......
0010 08 06 00 01 08 00 06 04 00 01 76 cf 76 37 d5 0a ..........v.v7..
0020 0a 09 09 09 00 00 00 00 00 00 ..........
Fixes: aff3d70a07 ("tun: allow to attach ebpf socket filter")
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changing API ndo_xdp_xmit to take a struct xdp_frame instead of struct
xdp_buff. This brings xdp_return_frame and ndp_xdp_xmit in sync.
This builds towards changing the API further to become a bulk API,
because xdp_buff is not a queue-able object while xdp_frame is.
V4: Adjust for commit 59655a5b6c ("tuntap: XDP_TX can use native XDP")
V7: Adjust for commit d9314c474d ("i40e: add support for XDP_REDIRECT")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changing API xdp_return_frame() to take struct xdp_frame as argument,
seems like a natural choice. But there are some subtle performance
details here that needs extra care, which is a deliberate choice.
When de-referencing xdp_frame on a remote CPU during DMA-TX
completion, result in the cache-line is change to "Shared"
state. Later when the page is reused for RX, then this xdp_frame
cache-line is written, which change the state to "Modified".
This situation already happens (naturally) for, virtio_net, tun and
cpumap as the xdp_frame pointer is the queued object. In tun and
cpumap, the ptr_ring is used for efficiently transferring cache-lines
(with pointers) between CPUs. Thus, the only option is to
de-referencing xdp_frame.
It is only the ixgbe driver that had an optimization, in which it can
avoid doing the de-reference of xdp_frame. The driver already have
TX-ring queue, which (in case of remote DMA-TX completion) have to be
transferred between CPUs anyhow. In this data area, we stored a
struct xdp_mem_info and a data pointer, which allowed us to avoid
de-referencing xdp_frame.
To compensate for this, a prefetchw is used for telling the cache
coherency protocol about our access pattern. My benchmarks show that
this prefetchw is enough to compensate the ixgbe driver.
V7: Adjust for commit d9314c474d ("i40e: add support for XDP_REDIRECT")
V8: Adjust for commit bd658dda42 ("net/mlx5e: Separate dma base address
and offset in dma_sync call")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the IDA infrastructure for getting a cyclic increasing ID number,
that is used for keeping track of each registered allocator per
RX-queue xdp_rxq_info. Instead of using the IDR infrastructure, which
uses a radix tree, use a dynamic rhashtable, for creating ID to
pointer lookup table, because this is faster.
The problem that is being solved here is that, the xdp_rxq_info
pointer (stored in xdp_buff) cannot be used directly, as the
guaranteed lifetime is too short. The info is needed on a
(potentially) remote CPU during DMA-TX completion time . In an
xdp_frame the xdp_mem_info is stored, when it got converted from an
xdp_buff, which is sufficient for the simple page refcnt based recycle
schemes.
For more advanced allocators there is a need to store a pointer to the
registered allocator. Thus, there is a need to guard the lifetime or
validity of the allocator pointer, which is done through this
rhashtable ID map to pointer. The removal and validity of of the
allocator and helper struct xdp_mem_allocator is guarded by RCU. The
allocator will be created by the driver, and registered with
xdp_rxq_info_reg_mem_model().
It is up-to debate who is responsible for freeing the allocator
pointer or invoking the allocator destructor function. In any case,
this must happen via RCU freeing.
Use the IDA infrastructure for getting a cyclic increasing ID number,
that is used for keeping track of each registered allocator per
RX-queue xdp_rxq_info.
V4: Per req of Jason Wang
- Use xdp_rxq_info_reg_mem_model() in all drivers implementing
XDP_REDIRECT, even-though it's not strictly necessary when
allocator==NULL for type MEM_TYPE_PAGE_SHARED (given it's zero).
V6: Per req of Alex Duyck
- Introduce rhashtable_lookup() call in later patch
V8: Address sparse should be static warnings (from kbuild test robot)
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
