linux.git/net/core/sysctl_net_core.c, branch v6.6

networking: Update to register_net_sysctl_sz

2023-08-15T22:26:18+00:00

Move from register_net_sysctl to register_net_sysctl_sz for all the
networking related files. Do this while making sure to mirror the NULL
assignments with a table_size of zero for the unprivileged users.

We need to move to the new function in preparation for when we change
SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do
so would erroneously allow ARRAY_SIZE() to be called on a pointer. We
hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all
the relevant net sysctl registering functions to register_net_sysctl_sz
in subsequent commits.

An additional size function was added to the following files in order to
calculate the size of an array that is defined in another file:
    include/net/ipv6.h
    net/ipv6/icmp.c
    net/ipv6/route.c
    net/ipv6/sysctl_net_ipv6.c

Signed-off-by: Joel Granados 
Signed-off-by: Luis Chamberlain

net/sysctl: Rename kvfree_rcu() to kvfree_rcu_mightsleep()

2023-04-05T13:48:04+00:00

The kfree_rcu() and kvfree_rcu() macros' single-argument forms are
deprecated.  Therefore switch to the new kfree_rcu_mightsleep() and
kvfree_rcu_mightsleep() variants. The goal is to avoid accidental use
of the single-argument forms, which can introduce functionality bugs in
atomic contexts and latency bugs in non-atomic contexts.

Acked-by: Jakub Kicinski 
Cc: Eric Dumazet 
Cc: David S. Miller 
Signed-off-by: Uladzislau Rezki (Sony) 
Signed-off-by: Paul E. McKenney 
Signed-off-by: Joel Fernandes (Google)

net: make default_rps_mask a per netns attribute

2023-02-20T11:22:54+00:00

That really was meant to be a per netns attribute from the beginning.

The idea is that once proper isolation is in place in the main
namespace, additional demux in the child namespaces will be redundant.
Let's make child netns default rps mask empty by default.

To avoid bloating the netns with a possibly large cpumask, allocate
it on-demand during the first write operation.

Signed-off-by: Paolo Abeni 
Signed-off-by: David S. Miller

net: introduce default_rps_mask netns attribute

2023-02-10T01:45:55+00:00

If RPS is enabled, this allows configuring a default rps
mask, which is effective since receive queue creation time.

A default RPS mask allows the system admin to ensure proper
isolation, avoiding races at network namespace or device
creation time.

The default RPS mask is initially empty, and can be
modified via a newly added sysctl entry.

Signed-off-by: Paolo Abeni 
Reviewed-by: Simon Horman 
Reviewed-by: Eric Dumazet 
Signed-off-by: Jakub Kicinski

net-sysctl: factor out cpumask parsing helper

2023-02-10T01:45:55+00:00

Will be used by the following patch to avoid code
duplication. No functional changes intended.

The only difference is that now flow_limit_cpu_sysctl() will
always compute the flow limit mask on each read operation,
even when read() will not return any byte to user-space.

Note that the new helper is placed under a new #ifdef at
the file start to better fit the usage in the later patch

Signed-off-by: Paolo Abeni 
Reviewed-by: Simon Horman 
Reviewed-by: Eric Dumazet 
Signed-off-by: Jakub Kicinski

sysctl: expose all net/core sysctls inside netns

2023-01-06T12:41:52+00:00

All were not visible to the non-priv users inside netns. However,
with 4ecb90090c84 ("sysctl: allow override of /proc/sys/net with
CAP_NET_ADMIN"), these vars are protected from getting modified.
A proc with capable(CAP_NET_ADMIN) can change the values so
not having them visible inside netns is just causing nuisance to
process that check certain values (e.g. net.core.somaxconn) and
see different behavior in root-netns vs. other-netns

Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Soheil Hassas Yeganeh 
Signed-off-by: Mahesh Bandewar 
Acked-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller

net: sysctl: remove unused variable long_max

2022-09-07T14:31:19+00:00

The variable long_max is replaced by bpf_jit_limit_max and no longer be
used. So remove it.

No functional change.

Signed-off-by: Liu Shixin 
Signed-off-by: David S. Miller

net: Fix data-races around weight_p and dev_weight_[rt]x_bias.

2022-08-24T12:46:57+00:00

While reading weight_p, it can be changed concurrently.  Thus, we need
to add READ_ONCE() to its reader.

Also, dev_[rt]x_weight can be read/written at the same time.  So, we
need to use READ_ONCE() and WRITE_ONCE() for its access.  Moreover, to
use the same weight_p while changing dev_[rt]x_weight, we add a mutex
in proc_do_dev_weight().

Fixes: 3d48b53fb2ae ("net: dev_weight: TX/RX orthogonality")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: David S. Miller

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

2022-05-23T23:07:14+00:00

Daniel Borkmann says:

====================
pull-request: bpf-next 2022-05-23

We've added 113 non-merge commits during the last 26 day(s) which contain
a total of 121 files changed, 7425 insertions(+), 1586 deletions(-).

The main changes are:

1) Speed up symbol resolution for kprobes multi-link attachments, from Jiri Olsa.

2) Add BPF dynamic pointer infrastructure e.g. to allow for dynamically sized ringbuf
   reservations without extra memory copies, from Joanne Koong.

3) Big batch of libbpf improvements towards libbpf 1.0 release, from Andrii Nakryiko.

4) Add BPF link iterator to traverse links via seq_file ops, from Dmitrii Dolgov.

5) Add source IP address to BPF tunnel key infrastructure, from Kaixi Fan.

6) Refine unprivileged BPF to disable only object-creating commands, from Alan Maguire.

7) Fix JIT blinding of ld_imm64 when they point to subprogs, from Alexei Starovoitov.

8) Add BPF access to mptcp_sock structures and their meta data, from Geliang Tang.

9) Add new BPF helper for access to remote CPU's BPF map elements, from Feng Zhou.

10) Allow attaching 64-bit cookie to BPF link of fentry/fexit/fmod_ret, from Kui-Feng Lee.

11) Follow-ups to typed pointer support in BPF maps, from Kumar Kartikeya Dwivedi.

12) Add busy-poll test cases to the XSK selftest suite, from Magnus Karlsson.

13) Improvements in BPF selftest test_progs subtest output, from Mykola Lysenko.

14) Fill bpf_prog_pack allocator areas with illegal instructions, from Song Liu.

15) Add generic batch operations for BPF map-in-map cases, from Takshak Chahande.

16) Make bpf_jit_enable more user friendly when permanently on 1, from Tiezhu Yang.

17) Fix an array overflow in bpf_trampoline_get_progs(), from Yuntao Wang.

====================

Link: https://lore.kernel.org/r/20220523223805.27931-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

net: add skb_defer_max sysctl

2022-05-16T10:33:59+00:00

commit 68822bdf76f1 ("net: generalize skb freeing
deferral to per-cpu lists") added another per-cpu
cache of skbs. It was expected to be small,
and an IPI was forced whenever the list reached 128
skbs.

We might need to be able to control more precisely
queue capacity and added latency.

An IPI is generated whenever queue reaches half capacity.

Default value of the new limit is 64.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller