Commit Graph

873496 Commits

Author SHA1 Message Date
Andrii Nakryiko
3dc5e05982 libbpf: Fix memory leak/double free issue
Coverity scan against Github libbpf code found the issue of not freeing memory and
leaving already freed memory still referenced from bpf_program. Fix it by
re-assigning successfully reallocated memory sooner.

Fixes: 2993e0515b ("tools/bpf: add support to read .BTF.ext sections")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-2-andriin@fb.com
2019-11-07 16:20:37 +01:00
Andrii Nakryiko
9656b346b2 libbpf: Fix negative FD close() in xsk_setup_xdp_prog()
Fix issue reported by static analysis (Coverity). If bpf_prog_get_fd_by_id()
fails, xsk_lookup_bpf_maps() will fail as well and clean-up code will attempt
close() with fd=-1. Fix by checking bpf_prog_get_fd_by_id() return result and
exiting early.

Fixes: 10a13bb40e ("libbpf: remove qidconf and better support external bpf programs.")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107054059.313884-1-andriin@fb.com
2019-11-07 16:15:27 +01:00
Ilya Leoshkevich
dab2e9eb18 s390/bpf: Remove unused SEEN_RET0, SEEN_REG_AX and ret0_ip
We don't need them since commit e1cf4befa2 ("bpf, s390x: remove
ld_abs/ld_ind") and commit a3212b8f15 ("bpf, s390x: remove obsolete
exception handling from div/mod").

Also, use BIT(n) instead of 1 << n, because checkpatch says so.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107114033.90505-1-iii@linux.ibm.com
2019-11-07 16:10:01 +01:00
Ilya Leoshkevich
6ad2e1a007 s390/bpf: Wrap JIT macro parameter usages in parentheses
This change does not alter JIT behavior; it only makes it possible to
safely invoke JIT macros with complex arguments in the future.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107113211.90105-1-iii@linux.ibm.com
2019-11-07 16:07:28 +01:00
Ilya Leoshkevich
166f11d11f s390/bpf: Use kvcalloc for addrs array
A BPF program may consist of 1m instructions, which means JIT
instruction-address mapping can be as large as 4m. s390 has
FORCE_MAX_ZONEORDER=9 (for memory hotplug reasons), which means maximum
kmalloc size is 1m. This makes it impossible to JIT programs with more
than 256k instructions.

Fix by using kvcalloc, which falls back to vmalloc for larger
allocations. An alternative would be to use a radix tree, but that is
not supported by bpf_prog_fill_jited_linfo.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107141838.92202-1-iii@linux.ibm.com
2019-11-07 16:05:55 +01:00
Ilya Leoshkevich
7e22077d0c tools, bpf_asm: Warn when jumps are out of range
When compiling larger programs with bpf_asm, it's possible to
accidentally exceed jt/jf range, in which case it won't complain, but
rather silently emit a truncated offset, leading to a "happy debugging"
situation.

Add a warning to help detecting such issues. It could be made an error
instead, but this might break compilation of existing code (which might
be working by accident).

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107100349.88976-1-iii@linux.ibm.com
2019-11-07 16:01:34 +01:00
Martin KaFai Lau
85d31dd070 bpf: Account for insn->off when doing bpf_probe_read_kernel
In the bpf interpreter mode, bpf_probe_read_kernel is used to read
from PTR_TO_BTF_ID's kernel object.  It currently missed considering
the insn->off.  This patch fixes it.

Fixes: 2a02759ef5 ("bpf: Add support for BTF pointers to interpreter")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191107014640.384083-1-kafai@fb.com
2019-11-06 21:52:52 -08:00
Andrii Nakryiko
ed57802121 libbpf: Simplify BPF_CORE_READ_BITFIELD_PROBED usage
Streamline BPF_CORE_READ_BITFIELD_PROBED interface to follow
BPF_CORE_READ_BITFIELD (direct) and BPF_CORE_READ, in general, i.e., just
return read result or 0, if underlying bpf_probe_read() failed.

In practice, real applications rarely check bpf_probe_read() result, because
it has to always work or otherwise it's a bug. So propagating internal
bpf_probe_read() error from this macro hurts usability without providing real
benefits in practice. This patch fixes the issue and simplifies usage,
noticeable even in selftest itself.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191106201500.2582438-1-andriin@fb.com
2019-11-06 13:54:59 -08:00
Andrii Nakryiko
65a052d537 selftests/bps: Clean up removed ints relocations negative tests
As part of 42765ede5c ("selftests/bpf: Remove too strict field offset relo
test cases"), few ints relocations negative (supposed to fail) tests were
removed, but not completely. Due to them being negative, some leftovers in
prog_tests/core_reloc.c went unnoticed. Clean them up.

Fixes: 42765ede5c ("selftests/bpf: Remove too strict field offset relo test cases")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191106173659.1978131-1-andriin@fb.com
2019-11-06 13:45:06 -08:00
Daniel Borkmann
f23c7ce341 Merge branch 'bpf-libbpf-bitfield-size-relo'
Andrii Nakryiko says:

====================
This patch set adds support for reading bitfields in a relocatable manner
through a set of relocations emitted by Clang, corresponding libbpf support
for those relocations, as well as abstracting details into
BPF_CORE_READ_BITFIELD/BPF_CORE_READ_BITFIELD_PROBED macro.

We also add support for capturing relocatable field size, so that BPF program
code can adjust its logic to actual amount of data it needs to operate on,
even if it changes between kernels. New convenience macro is added to
bpf_core_read.h (bpf_core_field_size(), in the same family of macro as
bpf_core_read() and bpf_core_field_exists()). Corresponding set of selftests
are added to excercise this logic and validate correctness in a variety of
scenarios.

Some of the overly strict logic of matching fields is relaxed to support wider
variety of scenarios. See patch #1 for that.

Patch #1 removes few overly strict test cases.
Patch #2 adds support for bitfield-related relocations.
Patch #3 adds some further adjustments to support generic field size
relocations and introduces bpf_core_field_size() macro.
Patch #4 tests bitfield reading.
Patch #5 tests field size relocations.

v1 -> v2:
  - added direct memory read-based macro and tests for bitfield reads.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-11-04 16:07:02 +01:00
Andrii Nakryiko
0b163565b9 selftests/bpf: Add field size relocation tests
Add test verifying correctness and logic of field size relocation support in
libbpf.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-6-andriin@fb.com
2019-11-04 16:06:56 +01:00
Andrii Nakryiko
8b1cb1c960 selftest/bpf: Add relocatable bitfield reading tests
Add a bunch of selftests verifying correctness of relocatable bitfield reading
support in libbpf. Both bpf_probe_read()-based and direct read-based bitfield
macros are tested. core_reloc.c "test_harness" is extended to support raw
tracepoint and new typed raw tracepoints as test BPF program types.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-5-andriin@fb.com
2019-11-04 16:06:56 +01:00
Andrii Nakryiko
94f060e984 libbpf: Add support for field size relocations
Add bpf_core_field_size() macro, capturing a relocation against field size.
Adjust bits of internal libbpf relocation logic to allow capturing size
relocations of various field types: arrays, structs/unions, enums, etc.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-4-andriin@fb.com
2019-11-04 16:06:56 +01:00
Andrii Nakryiko
ee26dade0e libbpf: Add support for relocatable bitfields
Add support for the new field relocation kinds, necessary to support
relocatable bitfield reads. Provide macro for abstracting necessary code doing
full relocatable bitfield extraction into u64 value. Two separate macros are
provided:
- BPF_CORE_READ_BITFIELD macro for direct memory read-enabled BPF programs
(e.g., typed raw tracepoints). It uses direct memory dereference to extract
bitfield backing integer value.
- BPF_CORE_READ_BITFIELD_PROBED macro for cases where bpf_probe_read() needs
to be used to extract same backing integer value.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-3-andriin@fb.com
2019-11-04 16:06:56 +01:00
Andrii Nakryiko
42765ede5c selftests/bpf: Remove too strict field offset relo test cases
As libbpf is going to gain support for more field relocations, including field
size, some restrictions about exact size match are going to be lifted. Remove
test cases that explicitly test such failures.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-2-andriin@fb.com
2019-11-04 16:06:56 +01:00
David S. Miller
1574cf83c7 mlx5-updates-2019-11-01
Misc updates for mlx5 netdev and core driver
 
 1) Steering Core: Replace CRC32 internal implementation with standard
    kernel lib.
 2) Steering Core: Support IPv4 and IPv6 mixed matcher.
 3) Steering Core: Lockless FTE read lookups
 4) TC: Bit sized fields rewrite support.
 5) FPGA: Standalone FPGA support.
 6) SRIOV: Reset VF parameters configurations on SRIOV disable.
 7) netdev: Dump WQs wqe descriptors on CQE with error events.
 8) MISC Cleanups.
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Merge tag 'mlx5-updates-2019-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mahameed says:

====================
mlx5-updates-2019-11-01

Misc updates for mlx5 netdev and core driver

1) Steering Core: Replace CRC32 internal implementation with standard
   kernel lib.
2) Steering Core: Support IPv4 and IPv6 mixed matcher.
3) Steering Core: Lockless FTE read lookups
4) TC: Bit sized fields rewrite support.
5) FPGA: Standalone FPGA support.
6) SRIOV: Reset VF parameters configurations on SRIOV disable.
7) netdev: Dump WQs wqe descriptors on CQE with error events.
8) MISC Cleanups.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 19:23:49 -08:00
YueHaibing
a37ac8ae66 mISDN: remove unused variable 'faxmodulation_s'
drivers/isdn/hardware/mISDN/mISDNisar.c:30:17:
 warning: faxmodulation_s defined but not used [-Wunused-const-variable=]

It is never used, so can be removed.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 19:10:30 -08:00
Vincent Cheng
3a6ba7dc77 ptp: Add a ptp clock driver for IDT ClockMatrix.
The IDT ClockMatrix (TM) family includes integrated devices that provide
eight PLL channels.  Each PLL channel can be independently configured as a
frequency synthesizer, jitter attenuator, digitally controlled
oscillator (DCO), or a digital phase lock loop (DPLL).  Typically
these devices are used as timing references and clock sources for PTP
applications.  This patch adds support for the device.

Co-developed-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Vincent Cheng <vincent.cheng.xh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:35:40 -08:00
Vincent Cheng
5c5e7aac63 dt-bindings: ptp: Add device tree binding for IDT ClockMatrix based PTP clock
Add device tree binding doc for the IDT ClockMatrix PTP clock.

Signed-off-by: Vincent Cheng <vincent.cheng.xh@renesas.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:35:40 -08:00
Francesco Ruggeri
fac6fce9bd net: icmp6: provide input address for traceroute6
traceroute6 output can be confusing, in that it shows the address
that a router would use to reach the sender, rather than the address
the packet used to reach the router.
Consider this case:

        ------------------------ N2
         |                    |
       ------              ------  N3  ----
       | R1 |              | R2 |------|H2|
       ------              ------      ----
         |                    |
        ------------------------ N1
                  |
                 ----
                 |H1|
                 ----

where H1's default route is through R1, and R1's default route is
through R2 over N2.
traceroute6 from H1 to H2 shows R2's address on N1 rather than on N2.

The script below can be used to reproduce this scenario.

traceroute6 output without this patch:

traceroute to 2000:103::4 (2000:103::4), 30 hops max, 80 byte packets
 1  2000:101::1 (2000:101::1)  0.036 ms  0.008 ms  0.006 ms
 2  2000:101::2 (2000:101::2)  0.011 ms  0.008 ms  0.007 ms
 3  2000:103::4 (2000:103::4)  0.013 ms  0.010 ms  0.009 ms

traceroute6 output with this patch:

traceroute to 2000:103::4 (2000:103::4), 30 hops max, 80 byte packets
 1  2000:101::1 (2000:101::1)  0.056 ms  0.019 ms  0.006 ms
 2  2000:102::2 (2000:102::2)  0.013 ms  0.008 ms  0.008 ms
 3  2000:103::4 (2000:103::4)  0.013 ms  0.009 ms  0.009 ms

#!/bin/bash
#
#        ------------------------ N2
#         |                    |
#       ------              ------  N3  ----
#       | R1 |              | R2 |------|H2|
#       ------              ------      ----
#         |                    |
#        ------------------------ N1
#                  |
#                 ----
#                 |H1|
#                 ----
#
# N1: 2000:101::/64
# N2: 2000:102::/64
# N3: 2000:103::/64
#
# R1's host part of address: 1
# R2's host part of address: 2
# H1's host part of address: 3
# H2's host part of address: 4
#
# For example:
# the IPv6 address of R1's interface on N2 is 2000:102::1/64
#
# Nets are implemented by macvlan interfaces (bridge mode) over
# dummy interfaces.
#

# Create net namespaces
ip netns add host1
ip netns add host2
ip netns add rtr1
ip netns add rtr2

# Create nets
ip link add net1 type dummy; ip link set net1 up
ip link add net2 type dummy; ip link set net2 up
ip link add net3 type dummy; ip link set net3 up

# Add interfaces to net1, move them to their nemaspaces
ip link add link net1 dev host1net1 type macvlan mode bridge
ip link set host1net1 netns host1
ip link add link net1 dev rtr1net1 type macvlan mode bridge
ip link set rtr1net1 netns rtr1
ip link add link net1 dev rtr2net1 type macvlan mode bridge
ip link set rtr2net1 netns rtr2

# Add interfaces to net2, move them to their nemaspaces
ip link add link net2 dev rtr1net2 type macvlan mode bridge
ip link set rtr1net2 netns rtr1
ip link add link net2 dev rtr2net2 type macvlan mode bridge
ip link set rtr2net2 netns rtr2

# Add interfaces to net3, move them to their nemaspaces
ip link add link net3 dev rtr2net3 type macvlan mode bridge
ip link set rtr2net3 netns rtr2
ip link add link net3 dev host2net3 type macvlan mode bridge
ip link set host2net3 netns host2

# Configure interfaces and routes in host1
ip netns exec host1 ip link set lo up
ip netns exec host1 ip link set host1net1 up
ip netns exec host1 ip -6 addr add 2000:101::3/64 dev host1net1
ip netns exec host1 ip -6 route add default via 2000:101::1

# Configure interfaces and routes in rtr1
ip netns exec rtr1 ip link set lo up
ip netns exec rtr1 ip link set rtr1net1 up
ip netns exec rtr1 ip -6 addr add 2000:101::1/64 dev rtr1net1
ip netns exec rtr1 ip link set rtr1net2 up
ip netns exec rtr1 ip -6 addr add 2000:102::1/64 dev rtr1net2
ip netns exec rtr1 ip -6 route add default via 2000:102::2
ip netns exec rtr1 sysctl net.ipv6.conf.all.forwarding=1

# Configure interfaces and routes in rtr2
ip netns exec rtr2 ip link set lo up
ip netns exec rtr2 ip link set rtr2net1 up
ip netns exec rtr2 ip -6 addr add 2000:101::2/64 dev rtr2net1
ip netns exec rtr2 ip link set rtr2net2 up
ip netns exec rtr2 ip -6 addr add 2000:102::2/64 dev rtr2net2
ip netns exec rtr2 ip link set rtr2net3 up
ip netns exec rtr2 ip -6 addr add 2000:103::2/64 dev rtr2net3
ip netns exec rtr2 sysctl net.ipv6.conf.all.forwarding=1

# Configure interfaces and routes in host2
ip netns exec host2 ip link set lo up
ip netns exec host2 ip link set host2net3 up
ip netns exec host2 ip -6 addr add 2000:103::4/64 dev host2net3
ip netns exec host2 ip -6 route add default via 2000:103::2

# Ping host2 from host1
ip netns exec host1 ping6 -c5 2000:103::4

# Traceroute host2 from host1
ip netns exec host1 traceroute6 2000:103::4

# Delete nets
ip link del net3
ip link del net2
ip link del net1

# Delete namespaces
ip netns del rtr2
ip netns del rtr1
ip netns del host2
ip netns del host1

Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Original-patch-by: Honggang Xu <hxu@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:26:53 -08:00
Tuong Lien
06e7c70c6e tipc: improve message bundling algorithm
As mentioned in commit e95584a889 ("tipc: fix unlimited bundling of
small messages"), the current message bundling algorithm is inefficient
that can generate bundles of only one payload message, that causes
unnecessary overheads for both the sender and receiver.

This commit re-designs the 'tipc_msg_make_bundle()' function (now named
as 'tipc_msg_try_bundle()'), so that when a message comes at the first
place, we will just check & keep a reference to it if the message is
suitable for bundling. The message buffer will be put into the link
backlog queue and processed as normal. Later on, when another one comes
we will make a bundle with the first message if possible and so on...
This way, a bundle if really needed will always consist of at least two
payload messages. Otherwise, we let the first buffer go its way without
any need of bundling, so reduce the overheads to zero.

Moreover, since now we have both the messages in hand, we can even
optimize the 'tipc_msg_bundle()' function, make bundle of a very large
(size ~ MSS) and small messages which is not with the current algorithm
e.g. [1400-byte message] + [10-byte message] (MTU = 1500).

Acked-by: Ying Xue <ying.xue@windreiver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:26:15 -08:00
Francesco Ruggeri
2adf81c0f7 net: icmp: use input address in traceroute
Even with icmp_errors_use_inbound_ifaddr set, traceroute returns the
primary address of the interface the packet was received on, even if
the path goes through a secondary address. In the example:

                    1.0.3.1/24
 ---- 1.0.1.3/24    1.0.1.1/24 ---- 1.0.2.1/24    1.0.2.4/24 ----
 |H1|--------------------------|R1|--------------------------|H2|
 ----            N1            ----            N2            ----

where 1.0.3.1/24 is R1's primary address on N1, traceroute from
H1 to H2 returns:

traceroute to 1.0.2.4 (1.0.2.4), 30 hops max, 60 byte packets
 1  1.0.3.1 (1.0.3.1)  0.018 ms  0.006 ms  0.006 ms
 2  1.0.2.4 (1.0.2.4)  0.021 ms  0.007 ms  0.007 ms

After applying this patch, it returns:

traceroute to 1.0.2.4 (1.0.2.4), 30 hops max, 60 byte packets
 1  1.0.1.1 (1.0.1.1)  0.033 ms  0.007 ms  0.006 ms
 2  1.0.2.4 (1.0.2.4)  0.011 ms  0.007 ms  0.007 ms

Original-patch-by: Bill Fenner <fenner@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:25:18 -08:00
David S. Miller
c219a16622 Merge branch 'optimize-openvswitch-flow-looking-up'
Tonghao Zhang says:

====================
optimize openvswitch flow looking up

This series patch optimize openvswitch for performance or simplify
codes.

Patch 1, 2, 4: Port Pravin B Shelar patches to
linux upstream with little changes.

Patch 5, 6, 7: Optimize the flow looking up and
simplify the flow hash.

Patch 8, 9: are bugfix.

The performance test is on Intel Xeon E5-2630 v4.
The test topology is show as below:

+-----------------------------------+
|   +---------------------------+   |
|   | eth0   ovs-switch    eth1 |   | Host0
|   +---------------------------+   |
+-----------------------------------+
      ^                       |
      |                       |
      |                       |
      |                       |
      |                       v
+-----+----+             +----+-----+
| netperf  | Host1       | netserver| Host2
+----------+             +----------+

We use netperf send the 64B packets, and insert 255+ flow-mask:
$ ovs-dpctl add-flow ovs-switch "in_port(1),eth(dst=00:01:00:00:00:00/ff:ff:ff:ff:ff:01),eth_type(0x0800),ipv4(frag=no)" 2
...
$ ovs-dpctl add-flow ovs-switch "in_port(1),eth(dst=00:ff:00:00:00:00/ff:ff:ff:ff:ff:ff),eth_type(0x0800),ipv4(frag=no)" 2
$
$ netperf -t UDP_STREAM -H 2.2.2.200 -l 40 -- -m 18

* Without series patch, throughput 8.28Mbps
* With series patch, throughput 46.05Mbps

v6:
some coding style fixes

v5:
rewrite patch 8, release flow-mask when freeing flow

v4:
access ma->count with READ_ONCE/WRITE_ONCE API. More information,
see patch 5 comments.

v3:
update ma point when realloc mask_array in patch 5

v2:
simplify codes. e.g. use kfree_rcu instead of call_rcu
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:04 -08:00
Tonghao Zhang
eec62eadd1 net: openvswitch: simplify the ovs_dp_cmd_new
use the specified functions to init resource.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:04 -08:00
Tonghao Zhang
4c76bf696a net: openvswitch: don't unlock mutex when changing the user_features fails
Unlocking of a not locked mutex is not allowed.
Other kernel thread may be in critical section while
we unlock it because of setting user_feature fail.

Fixes: 95a7233c4 ("net: openvswitch: Set OvS recirc_id from tc chain index")
Cc: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:04 -08:00
Tonghao Zhang
50b0e61b32 net: openvswitch: fix possible memleak on destroy flow-table
When we destroy the flow tables which may contain the flow_mask,
so release the flow mask struct.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
0a3e01371d net: openvswitch: add likely in flow_lookup
The most case *index < ma->max, and flow-mask is not NULL.
We add un/likely for performance.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
515b65a4b9 net: openvswitch: simplify the flow_hash
Simplify the code and remove the unnecessary BUILD_BUG_ON.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
57f7d7b916 net: openvswitch: optimize flow-mask looking up
The full looking up on flow table traverses all mask array.
If mask-array is too large, the number of invalid flow-mask
increase, performance will be drop.

One bad case, for example: M means flow-mask is valid and NULL
of flow-mask means deleted.

+-------------------------------------------+
| M | NULL | ...                  | NULL | M|
+-------------------------------------------+

In that case, without this patch, openvswitch will traverses all
mask array, because there will be one flow-mask in the tail. This
patch changes the way of flow-mask inserting and deleting, and the
mask array will be keep as below: there is not a NULL hole. In the
fast path, we can "break" "for" (not "continue") in flow_lookup
when we get a NULL flow-mask.

         "break"
            v
+-------------------------------------------+
| M | M |  NULL |...           | NULL | NULL|
+-------------------------------------------+

This patch don't optimize slow or control path, still using ma->max
to traverse. Slow path:
* tbl_mask_array_realloc
* ovs_flow_tbl_lookup_exact
* flow_mask_find

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
a7f35e78e7 net: openvswitch: optimize flow mask cache hash collision
Port the codes to linux upstream and with little changes.

Pravin B Shelar, says:
| In case hash collision on mask cache, OVS does extra flow
| lookup. Following patch avoid it.

Link: 0e6efbe271
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
1689754de6 net: openvswitch: shrink the mask array if necessary
When creating and inserting flow-mask, if there is no available
flow-mask, we realloc the mask array. When removing flow-mask,
if necessary, we shrink mask array.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
4bc63b1b53 net: openvswitch: convert mask list in mask array
Port the codes to linux upstream and with little changes.

Pravin B Shelar, says:
| mask caches index of mask in mask_list. On packet recv OVS
| need to traverse mask-list to get cached mask. Therefore array
| is better for retrieving cached mask. This also allows better
| cache replacement algorithm by directly checking mask's existence.

Link: d49fc3ff53
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
Tonghao Zhang
04b7d136d0 net: openvswitch: add flow-mask cache for performance
The idea of this optimization comes from a patch which
is committed in 2014, openvswitch community. The author
is Pravin B Shelar. In order to get high performance, I
implement it again. Later patches will use it.

Pravin B Shelar, says:
| On every packet OVS needs to lookup flow-table with every
| mask until it finds a match. The packet flow-key is first
| masked with mask in the list and then the masked key is
| looked up in flow-table. Therefore number of masks can
| affect packet processing performance.

Link: 5604935e4e
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:18:03 -08:00
David S. Miller
ae8a76fb8b Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-11-02

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

We've added 30 non-merge commits during the last 7 day(s) which contain
a total of 41 files changed, 1864 insertions(+), 474 deletions(-).

The main changes are:

1) Fix long standing user vs kernel access issue by introducing
   bpf_probe_read_user() and bpf_probe_read_kernel() helpers, from Daniel.

2) Accelerated xskmap lookup, from Björn and Maciej.

3) Support for automatic map pinning in libbpf, from Toke.

4) Cleanup of BTF-enabled raw tracepoints, from Alexei.

5) Various fixes to libbpf and selftests.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-02 15:29:58 -07:00
David S. Miller
d31e95585c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The only slightly tricky merge conflict was the netdevsim because the
mutex locking fix overlapped a lot of driver reload reorganization.

The rest were (relatively) trivial in nature.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-02 13:54:56 -07:00
Alexei Starovoitov
358fdb4562 Merge branch 'bpf_probe_read_user'
Daniel Borkmann says:

====================
This set adds probe_read_{user,kernel}(), probe_read_str_{user,kernel}()
helpers, fixes probe_write_user() helper and selftests. For details please
see individual patches.

Thanks!

v2 -> v3:
  - noticed two more things that are fixed in here:
   - bpf uapi helper description used 'int size' for *_str helpers, now u32
   - we need TASK_SIZE_MAX + guard page on x86-64 in patch 2 otherwise
     we'll trigger the 00c42373d3 warn as well, so full range covered now
v1 -> v2:
  - standardize unsafe_ptr terminology in uapi header comment (Andrii)
  - probe_read_{user,kernel}[_str] naming scheme (Andrii)
  - use global data in last test case, remove relaxed_maps (Andrii)
  - add strict non-pagefault kernel read funcs to avoid warning in
    kernel probe read helpers (Alexei)
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-11-02 12:45:15 -07:00
Daniel Borkmann
fa553d9b57 bpf, testing: Add selftest to read/write sockaddr from user space
Tested on x86-64 and Ilya was also kind enough to give it a spin on
s390x, both passing with probe_user:OK there. The test is using the
newly added bpf_probe_read_user() to dump sockaddr from connect call
into .bss BPF map and overrides the user buffer via bpf_probe_write_user():

  # ./test_progs
  [...]
  #17 pkt_md_access:OK
  #18 probe_user:OK
  #19 prog_run_xattr:OK
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/90f449d8af25354e05080e82fc6e2d3179da30ea.1572649915.git.daniel@iogearbox.net
2019-11-02 12:45:08 -07:00
Daniel Borkmann
50f9aa44ca bpf, testing: Convert prog tests to probe_read_{user, kernel}{, _str} helper
Use probe read *_{kernel,user}{,_str}() helpers instead of bpf_probe_read()
or bpf_probe_read_user_str() for program tests where appropriate.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/4a61d4b71ce3765587d8ef5cb93afa18515e5b3e.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:13 -07:00
Daniel Borkmann
251e2d337a bpf, samples: Use bpf_probe_read_user where appropriate
Use bpf_probe_read_user() helper instead of bpf_probe_read() for samples that
attach to kprobes probing on user addresses.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/5b0144b3f8e031ec5e2438bd7de8d7877e63bf2f.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:13 -07:00
Daniel Borkmann
6e07a63412 bpf: Switch BPF probe insns to bpf_probe_read_kernel
Commit 2a02759ef5 ("bpf: Add support for BTF pointers to interpreter")
explicitly states that the pointer to BTF object is a pointer to a kernel
object or NULL. Therefore we should also switch to using the strict kernel
probe helper which is restricted to kernel addresses only when architectures
have non-overlapping address spaces.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/d2b90827837685424a4b8008dfe0460558abfada.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Daniel Borkmann
6ae08ae3de bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers
The current bpf_probe_read() and bpf_probe_read_str() helpers are broken
in that they assume they can be used for probing memory access for kernel
space addresses /as well as/ user space addresses.

However, plain use of probe_kernel_read() for both cases will attempt to
always access kernel space address space given access is performed under
KERNEL_DS and some archs in-fact have overlapping address spaces where a
kernel pointer and user pointer would have the /same/ address value and
therefore accessing application memory via bpf_probe_read{,_str}() would
read garbage values.

Lets fix BPF side by making use of recently added 3d7081822f ("uaccess:
Add non-pagefault user-space read functions"). Unfortunately, the only way
to fix this status quo is to add dedicated bpf_probe_read_{user,kernel}()
and bpf_probe_read_{user,kernel}_str() helpers. The bpf_probe_read{,_str}()
helpers are kept as-is to retain their current behavior.

The two *_user() variants attempt the access always under USER_DS set, the
two *_kernel() variants will -EFAULT when accessing user memory if the
underlying architecture has non-overlapping address ranges, also avoiding
throwing the kernel warning via 00c42373d3 ("x86-64: add warning for
non-canonical user access address dereferences").

Fixes: a5e8c07059 ("bpf: add bpf_probe_read_str helper")
Fixes: 2541517c32 ("tracing, perf: Implement BPF programs attached to kprobes")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/796ee46e948bc808d54891a1108435f8652c6ca4.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Daniel Borkmann
eb1b668874 bpf: Make use of probe_user_write in probe write helper
Convert the bpf_probe_write_user() helper to probe_user_write() such that
writes are not attempted under KERNEL_DS anymore which is buggy as kernel
and user space pointers can have overlapping addresses. Also, given we have
the access_ok() check inside probe_user_write(), the helper doesn't need
to do it twice.

Fixes: 96ae522795 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/841c461781874c07a0ee404a454c3bc0459eed30.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Daniel Borkmann
75a1a607bb uaccess: Add strict non-pagefault kernel-space read function
Add two new probe_kernel_read_strict() and strncpy_from_unsafe_strict()
helpers which by default alias to the __probe_kernel_read() and the
__strncpy_from_unsafe(), respectively, but can be overridden by archs
which have non-overlapping address ranges for kernel space and user
space in order to bail out with -EFAULT when attempting to probe user
memory including non-canonical user access addresses [0]:

  4-level page tables:
    user-space mem: 0x0000000000000000 - 0x00007fffffffffff
    non-canonical:  0x0000800000000000 - 0xffff7fffffffffff

  5-level page tables:
    user-space mem: 0x0000000000000000 - 0x00ffffffffffffff
    non-canonical:  0x0100000000000000 - 0xfeffffffffffffff

The idea is that these helpers are complementary to the probe_user_read()
and strncpy_from_unsafe_user() which probe user-only memory. Both added
helpers here do the same, but for kernel-only addresses.

Both set of helpers are going to be used for BPF tracing. They also
explicitly avoid throwing the splat for non-canonical user addresses from
00c42373d3 ("x86-64: add warning for non-canonical user access address
dereferences").

For compat, the current probe_kernel_read() and strncpy_from_unsafe() are
left as-is.

  [0] Documentation/x86/x86_64/mm.txt

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: x86@kernel.org
Link: https://lore.kernel.org/bpf/eefeefd769aa5a013531f491a71f0936779e916b.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Daniel Borkmann
1d1585ca0f uaccess: Add non-pagefault user-space write function
Commit 3d7081822f ("uaccess: Add non-pagefault user-space read functions")
missed to add probe write function, therefore factor out a probe_write_common()
helper with most logic of probe_kernel_write() except setting KERNEL_DS, and
add a new probe_user_write() helper so it can be used from BPF side.

Again, on some archs, the user address space and kernel address space can
co-exist and be overlapping, so in such case, setting KERNEL_DS would mean
that the given address is treated as being in kernel address space.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/bpf/9df2542e68141bfa3addde631441ee45503856a8.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Alexei Starovoitov
e1cb7d2d60 Merge branch 'map-pinning'
Toke Høiland-Jørgensen says:

====================
This series adds support to libbpf for reading 'pinning' settings from BTF-based
map definitions. It introduces a new open option which can set the pinning path;
if no path is set, /sys/fs/bpf is used as the default. Callers can customise the
pinning between open and load by setting the pin path per map, and still get the
automatic reuse feature.

The semantics of the pinning is similar to the iproute2 "PIN_GLOBAL" setting,
and the eventual goal is to move the iproute2 implementation to be based on
libbpf and the functions introduced in this series.

Changelog:

v6:
  - Fix leak of struct bpf_object in selftest
  - Make struct bpf_map arg const in bpf_map__is_pinned() and bpf_map__get_pin_path()

v5:
  - Don't pin maps with pinning set, but with a value of LIBBPF_PIN_NONE
  - Add a few more selftests:
    - Should not pin map with pinning set, but value LIBBPF_PIN_NONE
    - Should fail to load a map with an invalid pinning value
    - Should fail to re-use maps with parameter mismatch
  - Alphabetise libbpf.map
  - Whitespace and typo fixes

v4:
  - Don't check key_type_id and value_type_id when checking for map reuse
    compatibility.
  - Move building of map->pin_path into init_user_btf_map()
  - Get rid of 'pinning' attribute in struct bpf_map
  - Make sure we also create parent directory on auto-pin (new patch 3).
  - Abort the selftest on error instead of attempting to continue.
  - Support unpinning all pinned maps with bpf_object__unpin_maps(obj, NULL)
  - Support pinning at map->pin_path with bpf_object__pin_maps(obj, NULL)
  - Make re-pinning a map at the same path a noop
  - Rename the open option to pin_root_path
  - Add a bunch more self-tests for pin_maps(NULL) and unpin_maps(NULL)
  - Fix a couple of smaller nits

v3:
  - Drop bpf_object__pin_maps_opts() and just use an open option to customise
    the pin path; also don't touch bpf_object__{un,}pin_maps()
  - Integrate pinning and reuse into bpf_object__create_maps() instead of having
    multiple loops though the map structure
  - Make errors in map reuse and pinning fatal to the load procedure
  - Add selftest to exercise pinning feature
  - Rebase series to latest bpf-next

v2:
  - Drop patch that adds mounting of bpffs
  - Only support a single value of the pinning attribute
  - Add patch to fixup error handling in reuse_fd()
  - Implement the full automatic pinning and map reuse logic on load
====================

Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-11-02 12:35:12 -07:00
Toke Høiland-Jørgensen
2f4a32cc83 selftests: Add tests for automatic map pinning
This adds a new BPF selftest to exercise the new automatic map pinning
code.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157269298209.394725.15420085139296213182.stgit@toke.dk
2019-11-02 12:35:07 -07:00
Toke Høiland-Jørgensen
57a00f4164 libbpf: Add auto-pinning of maps when loading BPF objects
This adds support to libbpf for setting map pinning information as part of
the BTF map declaration, to get automatic map pinning (and reuse) on load.
The pinning type currently only supports a single PIN_BY_NAME mode, where
each map will be pinned by its name in a path that can be overridden, but
defaults to /sys/fs/bpf.

Since auto-pinning only does something if any maps actually have a
'pinning' BTF attribute set, we default the new option to enabled, on the
assumption that seamless pinning is what most callers want.

When a map has a pin_path set at load time, libbpf will compare the map
pinned at that location (if any), and if the attributes match, will re-use
that map instead of creating a new one. If no existing map is found, the
newly created map will instead be pinned at the location.

Programs wanting to customise the pinning can override the pinning paths
using bpf_map__set_pin_path() before calling bpf_object__load() (including
setting it to NULL to disable pinning of a particular map).

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157269298092.394725.3966306029218559681.stgit@toke.dk
2019-11-02 12:35:07 -07:00
Toke Høiland-Jørgensen
196f8487f5 libbpf: Move directory creation into _pin() functions
The existing pin_*() functions all try to create the parent directory
before pinning. Move this check into the per-object _pin() functions
instead. This ensures consistent behaviour when auto-pinning is
added (which doesn't go through the top-level pin_maps() function), at the
cost of a few more calls to mkdir().

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157269297985.394725.5882630952992598610.stgit@toke.dk
2019-11-02 12:35:07 -07:00
Toke Høiland-Jørgensen
4580b25fce libbpf: Store map pin path and status in struct bpf_map
Support storing and setting a pin path in struct bpf_map, which can be used
for automatic pinning. Also store the pin status so we can avoid attempts
to re-pin a map that has already been pinned (or reused from a previous
pinning).

The behaviour of bpf_object__{un,}pin_maps() is changed so that if it is
called with a NULL path argument (which was previously illegal), it will
(un)pin only those maps that have a pin_path set.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157269297876.394725.14782206533681896279.stgit@toke.dk
2019-11-02 12:35:07 -07:00
Toke Høiland-Jørgensen
d1b4574a4b libbpf: Fix error handling in bpf_map__reuse_fd()
bpf_map__reuse_fd() was calling close() in the error path before returning
an error value based on errno. However, close can change errno, so that can
lead to potentially misleading error messages. Instead, explicitly store
errno in the err variable before each goto.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157269297769.394725.12634985106772698611.stgit@toke.dk
2019-11-02 12:35:06 -07:00