selftests/tc-testing: update test definitions for local resources

With resources localized on a per test basis, some tests definitions
either contain redundant commands, were wrong or could be simplified.
Update all of them to match the new requirements.

Tested-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests/tc-testings: add sample action deleting test case

Test 3872: Delete sample action with valid index
Test a394: Delete sample action with invalid index

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched: act_sample: fix divide by zero in the traffic path

the control path of 'sample' action does not validate the value of 'rate'
provided by the user, but then it uses it as divisor in the traffic path.
Validate it in tcf_sample_init(), and return -EINVAL with a proper extack
message in case that value is zero, to fix a splat with the script below:

# tc f a dev test0 egress matchall action sample rate 0 group 1 index 2
# tc -s a s action sample
total acts 1

action order 0: sample rate 1/0 group 1 pipe
index 2 ref 1 bind 1 installed 19 sec used 19 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
# ping 192.0.2.1 -I test0 -c1 -q

divide error: 0000 [#1] SMP PTI
CPU: 1 PID: 6192 Comm: ping Not tainted 5.1.0-rc2.diag2+ #591
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
RIP: 0010:tcf_sample_act+0x9e/0x1e0 [act_sample]
Code: 6a f1 85 c0 74 0d 80 3d 83 1a 00 00 00 0f 84 9c 00 00 00 4d 85 e4 0f 84 85 00 00 00 e8 9b d7 9c f1 44 8b 8b e0 00 00 00 31 d2 <41> f7 f1 85 d2 75 70 f6 85 83 00 00 00 10 48 8b 45 10 8b 88 08 01
RSP: 0018:ffffae320190ba30 EFLAGS: 00010246
RAX: 00000000b0677d21 RBX: ffff8af1ed9ec000 RCX: 0000000059a9fe49
RDX: 0000000000000000 RSI: 000000000c7e33b7 RDI: ffff8af23daa0af0
RBP: ffff8af1ee11b200 R08: 0000000074fcaf7e R09: 0000000000000000
R10: 0000000000000050 R11: ffffffffb3088680 R12: ffff8af232307f80
R13: 0000000000000003 R14: ffff8af1ed9ec000 R15: 0000000000000000
FS: 00007fe9c6d2f740(0000) GS:ffff8af23da80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff6772f000 CR3: 00000000746a2004 CR4: 00000000001606e0
Call Trace:
tcf_action_exec+0x7c/0x1c0
tcf_classify+0x57/0x160
__dev_queue_xmit+0x3dc/0xd10
ip_finish_output2+0x257/0x6d0
ip_output+0x75/0x280
ip_send_skb+0x15/0x40
raw_sendmsg+0xae3/0x1410
sock_sendmsg+0x36/0x40
__sys_sendto+0x10e/0x140
__x64_sys_sendto+0x24/0x30
do_syscall_64+0x60/0x210
entry_SYSCALL_64_after_hwframe+0x49/0xbe
[...]
Kernel panic - not syncing: Fatal exception in interrupt

Add a TDC selftest to document that 'rate' is now being validated.

Reported-by: Matteo Croce <mcroce@redhat.com>
Fixes: 5c5670fae430 ("net/sched: Introduce sample tc action")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Yotam Gigi <yotam.gi@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched: act_sample: validate the control action inside init()

the following script:

# tc qdisc add dev crash0 clsact
# tc filter add dev crash0 egress matchall \
> action sample rate 1024 group 4 pass index 90
# tc actions replace action sample \
> rate 1024 group 4 goto chain 42 index 90 cookie c1a0c1a0
# tc actions show action sample

had the following output:

Error: Failed to init TC action chain.
We have an error talking to the kernel
total acts 1

action order 0: sample rate 1/1024 group 4 goto chain 42
index 90 ref 2 bind 1
cookie c1a0c1a0

Then, the first packet transmitted by crash0 made the kernel crash:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
#PF error: [normal kernel read fault]
PGD 8000000079966067 P4D 8000000079966067 PUD 7987b067 PMD 0
Oops: 0000 [#1] SMP PTI
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.0.0-rc4.gotochain_crash+ #536
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:tcf_action_exec+0xb8/0x100
Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3
RSP: 0018:ffffbee60033fad0 EFLAGS: 00010246
RAX: 000000002000002a RBX: ffff99d7ae6e3b00 RCX: 00000000e555df9b
RDX: 0000000000000000 RSI: 00000000b0352718 RDI: ffff99d7fda1fcf0
RBP: ffffbee60033fb70 R08: 0000000070731ab1 R09: 0000000000000400
R10: 0000000000000000 R11: ffff99d7ac733838 R12: ffff99d7f3c2be00
R13: ffff99d7f3c2be08 R14: 0000000000000001 R15: ffff99d7f3c2b600
FS: 0000000000000000(0000) GS:ffff99d7fda00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000797de006 CR4: 00000000001606f0
Call Trace:
tcf_classify+0x58/0x120
__dev_queue_xmit+0x40a/0x890
? ndisc_next_option+0x50/0x50
? ___neigh_create+0x4d5/0x680
? ip6_finish_output2+0x1b5/0x590
ip6_finish_output2+0x1b5/0x590
? ip6_output+0x68/0x110
ip6_output+0x68/0x110
? nf_hook.constprop.28+0x79/0xc0
ndisc_send_skb+0x248/0x2e0
ndisc_send_ns+0xf8/0x200
? addrconf_dad_work+0x389/0x4b0
addrconf_dad_work+0x389/0x4b0
? __switch_to_asm+0x34/0x70
? process_one_work+0x195/0x380
? addrconf_dad_completed+0x370/0x370
process_one_work+0x195/0x380
worker_thread+0x30/0x390
? process_one_work+0x380/0x380
kthread+0x113/0x130
? kthread_park+0x90/0x90
ret_from_fork+0x35/0x40
Modules linked in: act_sample psample veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 crct10dif_pclmul crc32_pclmul ghash_clmulni_intel mbcache jbd2 snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device aesni_intel crypto_simd snd_pcm cryptd glue_helper snd_timer joydev snd pcspkr virtio_balloon i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect virtio_net sysimgblt fb_sys_fops net_failover ttm failover virtio_blk virtio_console drm ata_piix serio_raw crc32c_intel libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod
CR2: 0000000000000000

Validating the control action within tcf_sample_init() proved to fix the
above issue. A TDC selftest is added to verify the correct behavior.

Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain")
Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tc-testing: add sample action tests

Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>