linux.git/net/core, branch v5.10

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2020-12-10T22:29:30+00:00

Alexei Starovoitov says:

====================
pull-request: bpf 2020-12-10

The following pull-request contains BPF updates for your *net* tree.

We've added 21 non-merge commits during the last 12 day(s) which contain
a total of 21 files changed, 163 insertions(+), 88 deletions(-).

The main changes are:

1) Fix propagation of 32-bit signed bounds from 64-bit bounds, from Alexei.

2) Fix ring_buffer__poll() return value, from Andrii.

3) Fix race in lwt_bpf, from Cong.

4) Fix test_offload, from Toke.

5) Various xsk fixes.

Please consider pulling these changes from:

  git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git

Thanks a lot!

Also thanks to reporters, reviewers and testers of commits in this pull-request:

Cong Wang, Hulk Robot, Jakub Kicinski, Jean-Philippe Brucker, John
Fastabend, Magnus Karlsson, Maxim Mikityanskiy, Yonghong Song
====================

Signed-off-by: David S. Miller

net: flow_offload: Fix memory leak for indirect flow block

2020-12-10T00:08:33+00:00

The offending commit introduces a cleanup callback that is invoked
when the driver module is removed to clean up the tunnel device
flow block. But it returns on the first iteration of the for loop.
The remaining indirect flow blocks will never be freed.

Fixes: 1fac52da5942 ("net: flow_offload: consolidate indirect flow_block infrastructure")
CC: Pablo Neira Ayuso 
Signed-off-by: Chris Mi 
Reviewed-by: Roi Dayan

xdp: Remove the xdp_attachment_flags_ok() callback

2020-12-09T15:27:42+00:00

Since commit 7f0a838254bd ("bpf, xdp: Maintain info on attached XDP BPF
programs in net_device"), the XDP program attachment info is now maintained
in the core code. This interacts badly with the xdp_attachment_flags_ok()
check that prevents unloading an XDP program with different load flags than
it was loaded with. In practice, two kinds of failures are seen:

- An XDP program loaded without specifying a mode (and which then ends up
  in driver mode) cannot be unloaded if the program mode is specified on
  unload.

- The dev_xdp_uninstall() hook always calls the driver callback with the
  mode set to the type of the program but an empty flags argument, which
  means the flags_ok() check prevents the program from being removed,
  leading to bpf prog reference leaks.

The original reason this check was added was to avoid ambiguity when
multiple programs were loaded. With the way the checks are done in the core
now, this is quite simple to enforce in the core code, so let's add a check
there and get rid of the xdp_attachment_flags_ok() callback entirely.

Fixes: 7f0a838254bd ("bpf, xdp: Maintain info on attached XDP BPF programs in net_device")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: Daniel Borkmann 
Acked-by: Jakub Kicinski 
Link: https://lore.kernel.org/bpf/160752225751.110217.10267659521308669050.stgit@toke.dk

lwt_bpf: Replace preempt_disable() with migrate_disable()

2020-12-07T19:53:40+00:00

migrate_disable() is just a wrapper for preempt_disable() in
non-RT kernel. It is safe to replace it, and RT kernel will
benefit.

Note that it is introduced since Feb 2020.

Suggested-by: Alexei Starovoitov 
Signed-off-by: Cong Wang 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20201205075946.497763-2-xiyou.wangcong@gmail.com

lwt: Disable BH too in run_lwt_bpf()

2020-12-07T19:53:39+00:00

The per-cpu bpf_redirect_info is shared among all skb_do_redirect()
and BPF redirect helpers. Callers on RX path are all in BH context,
disabling preemption is not sufficient to prevent BH interruption.

In production, we observed strange packet drops because of the race
condition between LWT xmit and TC ingress, and we verified this issue
is fixed after we disable BH.

Although this bug was technically introduced from the beginning, that
is commit 3a0af8fd61f9 ("bpf: BPF for lightweight tunnel infrastructure"),
at that time call_rcu() had to be call_rcu_bh() to match the RCU context.
So this patch may not work well before RCU flavor consolidation has been
completed around v5.0.

Update the comments above the code too, as call_rcu() is now BH friendly.

Signed-off-by: Dongdong Wang 
Signed-off-by: Alexei Starovoitov 
Reviewed-by: Cong Wang 
Link: https://lore.kernel.org/bpf/20201205075946.497763-1-xiyou.wangcong@gmail.com

net: skbuff: ensure LSE is pullable before decrementing the MPLS ttl

2020-12-03T19:13:21+00:00

skb_mpls_dec_ttl() reads the LSE without ensuring that it is contained in
the skb "linear" area. Fix this calling pskb_may_pull() before reading the
current ttl.

Found by code inspection.

Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC")
Reported-by: Marcelo Ricardo Leitner 
Signed-off-by: Davide Caratti 
Link: https://lore.kernel.org/r/53659f28be8bc336c113b5254dc637cc76bbae91.1606987074.git.dcaratti@redhat.com
Signed-off-by: Jakub Kicinski

xdp: Handle MEM_TYPE_XSK_BUFF_POOL correctly in xdp_return_buff()

2020-11-30T22:00:26+00:00

It turns out that it does exist a path where xdp_return_buff() is
being passed an XDP buffer of type MEM_TYPE_XSK_BUFF_POOL. This path
is when AF_XDP zero-copy mode is enabled, and a buffer is redirected
to a DEVMAP with an attached XDP program that drops the buffer.

This change simply puts the handling of MEM_TYPE_XSK_BUFF_POOL back
into xdp_return_buff().

Fixes: 82c41671ca4f ("xdp: Simplify xdp_return_{frame, frame_rx_napi, buff}")
Reported-by: Maxim Mikityanskiy 
Signed-off-by: Björn Töpel 
Signed-off-by: Daniel Borkmann 
Acked-by: Maxim Mikityanskiy 
Link: https://lore.kernel.org/bpf/20201127171726.123627-1-bjorn.topel@gmail.com

Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2020-11-28T20:04:57+00:00

Daniel Borkmann says:

====================
pull-request: bpf 2020-11-28

1) Do not reference the skb for xsk's generic TX side since when looped
   back into RX it might crash in generic XDP, from Björn Töpel.

2) Fix umem cleanup on a partially set up xsk socket when being destroyed,
   from Magnus Karlsson.

3) Fix an incorrect netdev reference count when failing xsk_bind() operation,
   from Marek Majtyka.

4) Fix bpftool to set an error code on failed calloc() in build_btf_type_table(),
   from Zhen Lei.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Add MAINTAINERS entry for BPF LSM
  bpftool: Fix error return value in build_btf_type_table
  net, xsk: Avoid taking multiple skbuff references
  xsk: Fix incorrect netdev reference count
  xsk: Fix umem cleanup bug at socket destruct
  MAINTAINERS: Update XDP and AF_XDP entries
====================

Link: https://lore.kernel.org/r/20201128005104.1205-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

sock: set sk_err to ee_errno on dequeue from errq

2020-11-27T19:07:06+00:00

When setting sk_err, set it to ee_errno, not ee_origin.

Commit f5f99309fa74 ("sock: do not set sk_err in
sock_dequeue_err_skb") disabled updating sk_err on errq dequeue,
which is correct for most error types (origins):

  -       sk->sk_err = err;

Commit 38b257938ac6 ("sock: reset sk_err when the error queue is
empty") reenabled the behavior for IMCP origins, which do require it:

  +       if (icmp_next)
  +               sk->sk_err = SKB_EXT_ERR(skb_next)->ee.ee_origin;

But read from ee_errno.

Fixes: 38b257938ac6 ("sock: reset sk_err when the error queue is empty")
Reported-by: Ayush Ranjan 
Signed-off-by: Willem de Bruijn 
Acked-by: Soheil Hassas Yeganeh 
Link: https://lore.kernel.org/r/20201126151220.2819322-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski

devlink: Make sure devlink instance and port are in same net namespace

2020-11-26T01:26:34+00:00

When devlink reload operation is not used, netdev of an Ethernet port may
be present in different net namespace than the net namespace of the
devlink instance.

Ensure that both the devlink instance and devlink port netdev are located
in same net namespace.

Fixes: 070c63f20f6c ("net: devlink: allow to change namespaces during reload")
Signed-off-by: Parav Pandit 
Signed-off-by: Jakub Kicinski