提交 · 816fba3529040d253cef0047bdef850014e746b9 · openeuler / Kernel

04 12月, 2016 29 次提交

Merge branch 'samples-bpf-automated-cgroup-tests' · 816fba35

由 David S. Miller 提交于 12月 03, 2016

Sargun Dhillon says:

====================
samples, bpf: Refactor; Add automated tests for cgroups

These two patches are around refactoring out some old, reusable code from the
existing test_current_task_under_cgroup_user test, and adding a new, automated
test.

There is some generic cgroupsv2 setup & cleanup code, given that most
environment still don't have it setup by default. With this code, we're able
to pretty easily add an automated test for future cgroupsv2 functionality.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

816fba35

samples, bpf: Add automated test for cgroup filter attachments · 9b474ece

由 Sargun Dhillon 提交于 12月 02, 2016

This patch adds the sample program test_cgrp2_attach2. This program is
similar to test_cgrp2_attach, but it performs automated testing of the
cgroupv2 BPF attached filters. It runs the following checks:
* Simple filter attachment
* Application of filters to child cgroups
* Overriding filters on child cgroups
	* Checking that this still works when the parent filter is removed

The filters that are used here are simply allow all / deny all filters, so
it isn't checking the actual functionality of the filters, but rather
the behaviour  around detachment / attachment. If net_cls is enabled,
this test will fail.
Signed-off-by: NSargun Dhillon <sargun@sargun.me>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

9b474ece

samples, bpf: Refactor test_current_task_under_cgroup - separate out helpers · 1a922fee

由 Sargun Dhillon 提交于 12月 02, 2016

This patch modifies test_current_task_under_cgroup_user. The test has
several helpers around creating a temporary environment for cgroup
testing, and moving the current task around cgroups. This set of
helpers can then be used in other tests.
Signed-off-by: NSargun Dhillon <sargun@sargun.me>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

1a922fee

samples/bpf: silence compiler warnings · 69a9d09b

由 Alexei Starovoitov 提交于 12月 01, 2016

silence some of the clang compiler warnings like:
include/linux/fs.h:2693:9: warning: comparison of unsigned enum expression < 0 is always false
arch/x86/include/asm/processor.h:491:30: warning: taking address of packed member 'sp0' of class or structure 'x86_hw_tss' may result in an unaligned pointer value
include/linux/cgroup-defs.h:326:16: warning: field 'cgrp' with variable sized type 'struct cgroup' not at the end of a struct or class is a GNU extension
since they add too much noise to samples/bpf/ build.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

69a9d09b

netns: fix net_generic() "id - 1" bloat · 6af2d5ff

由 Alexey Dobriyan 提交于 12月 02, 2016

net_generic() function is both a) inline and b) used ~600 times.

It has the following code inside

		...
	ptr = ng->ptr[id - 1];
		...

"id" is never compile time constant so compiler is forced to subtract 1.
And those decrements or LEA [r32 - 1] instructions add up.

We also start id'ing from 1 to catch bugs where pernet sybsystem id
is not initialized and 0. This is quite pointless idea (nothing will
work or immediate interference with first registered subsystem) in
general but it hints what needs to be done for code size reduction.

Namely, overlaying allocation of pointer array and fixed part of
structure in the beginning and using usual base-0 addressing.

Ids are just cookies, their exact values do not matter, so lets start
with 3 on x86_64.

Code size savings (oh boy): -4.2 KB

As usual, ignore the initial compiler stupidity part of the table.

	add/remove: 0/0 grow/shrink: 12/670 up/down: 89/-4297 (-4208)
	function                                     old     new   delta
	tipc_nametbl_insert_publ                    1250    1270     +20
	nlmclnt_lookup_host                          686     703     +17
	nfsd4_encode_fattr                          5930    5941     +11
	nfs_get_client                              1050    1061     +11
	register_pernet_operations                   333     342      +9
	tcf_mirred_init                              843     849      +6
	tcf_bpf_init                                1143    1149      +6
	gss_setup_upcall                             990     994      +4
	idmap_name_to_id                             432     434      +2
	ops_init                                     274     275      +1
	nfsd_inject_forget_client                    259     260      +1
	nfs4_alloc_client                            612     613      +1
	tunnel_key_walker                            164     163      -1

		...

	tipc_bcbase_select_primary                   392     360     -32
	mac80211_hwsim_new_radio                    2808    2767     -41
	ipip6_tunnel_ioctl                          2228    2186     -42
	tipc_bcast_rcv                               715     672     -43
	tipc_link_build_proto_msg                   1140    1089     -51
	nfsd4_lock                                  3851    3796     -55
	tipc_mon_rcv                                1012     956     -56
	Total: Before=156643951, After=156639743, chg -0.00%
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

6af2d5ff

netns: add dummy struct inside "struct net_generic" · 9bfc7b99

由 Alexey Dobriyan 提交于 12月 02, 2016

This is precursor to fixing "[id - 1]" bloat inside net_generic().

Name "s" is chosen to complement name "u" often used for dummy unions.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

9bfc7b99

netns: publish net_generic correctly · 1a9a0592

由 Alexey Dobriyan 提交于 12月 02, 2016

Publishing net_generic pointer is done with silly mistake: new array is
published BEFORE setting freshly acquired pernet subsystem pointer.

	memcpy
	rcu_assign_pointer
	kfree_rcu
	ng->ptr[id - 1] = data;

This bug was introduced with commit dec827d1
("[NETNS]: The generic per-net pointers.") in the glorious days of
chopping networking stack into containers proper 8.5 years ago (whee...)

How it didn't trigger for so long?
Well, you need quite specific set of conditions:

*) race window opens once per pernet subsystem addition
   (read: modprobe or boot)

*) not every pernet subsystem is eligible (need ->id and ->size)

*) not every pernet subsystem is vulnerable (need incorrect or absense
   of ordering of register_pernet_sybsys() and actually using net_generic())

*) to hide the bug even more, default is to preallocate 13 pointers which
   is actually quite a lot. You need IPv6, netfilter, bridging etc together
   loaded to trigger reallocation in the first place. Trimmed down
   config are OK.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

1a9a0592

netlink: 2-clause nla_ok() · 4f7df337

由 Alexey Dobriyan 提交于 12月 02, 2016

nla_ok() consists of 3 clauses:

	1) int rem >= (int)sizeof(struct nlattr)

	2) u16 nla_len >= sizeof(struct nlattr)

	3) u16 nla_len <= int rem

The statement is that clause (1) is redundant.

What it does is ensuring that "rem" is a positive number,
so that in clause (3) positive number will be compared to positive number
with no problems.

However, "u16" fully fits into "int" and integers do not change value
when upcasting even to signed type. Negative integers will be rejected
by clause (3) just fine. Small positive integers will be rejected
by transitivity of comparison operator.

NOTE: all of the above DOES NOT apply to nlmsg_ok() where ->nlmsg_len is
u32(!), so 3 clauses AND A CAST TO INT are necessary.

Obligatory space savings report: -1.6 KB

	$ ./scripts/bloat-o-meter ../vmlinux-000* ../vmlinux-001*
	add/remove: 0/0 grow/shrink: 3/63 up/down: 35/-1692 (-1657)
	function                                     old     new   delta
	validate_scan_freqs                          142     155     +13
	tcf_em_tree_validate                         867     879     +12
	dcbnl_ieee_del                               328     338     +10
	netlbl_cipsov4_add_common.isra               218     215      -3
		...
	ovs_nla_put_actions                          888     806     -82
	netlbl_cipsov4_add_std                      1648    1566     -82
	nl80211_parse_sched_scan                    2889    2780    -109
	ip_tun_from_nlattr                          3086    2945    -141
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

4f7df337

staging: wilc1000: use reset to set mac header · fe211cd8