Commit Graph

796761 Commits

Author SHA1 Message Date
Martin KaFai Lau
2667a2626f bpf: btf: Add BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
This patch adds BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
to support the function debug info.

BTF_KIND_FUNC_PROTO must not have a name (i.e. !t->name_off)
and it is followed by >= 0 'struct bpf_param' objects to
describe the function arguments.

The BTF_KIND_FUNC must have a valid name and it must
refer back to a BTF_KIND_FUNC_PROTO.

The above is the conclusion after the discussion between
Edward Cree, Alexei, Daniel, Yonghong and Martin.

By combining BTF_KIND_FUNC and BTF_LIND_FUNC_PROTO,
a complete function signature can be obtained.  It will be
used in the later patches to learn the function signature of
a running bpf program.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-20 10:54:38 -08:00
Martin KaFai Lau
b47a0bd23e bpf: btf: Break up btf_type_is_void()
This patch breaks up btf_type_is_void() into
btf_type_is_void() and btf_type_is_fwd().

It also adds btf_type_nosize() to better describe it is
testing a type has nosize info.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-20 10:54:38 -08:00
Daniel Borkmann
bbe5d311be Merge branch 'bpf-zero-hash-seed'
Lorenz Bauer says:

====================
Allow forcing the seed of a hash table to zero, for deterministic
execution during benchmarking and testing.

Changes from v2:
* Change ordering of BPF_F_ZERO_SEED in linux/bpf.h

Comments adressed from v1:
* Add comment to discourage production use to linux/bpf.h
* Require CAP_SYS_ADMIN
====================

Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-20 00:53:41 +01:00
Lorenz Bauer
bf5d68c730 tools: add selftest for BPF_F_ZERO_SEED
Check that iterating two separate hash maps produces the same
order of keys if BPF_F_ZERO_SEED is used.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-20 00:53:40 +01:00
Lorenz Bauer
608114e441 tools: sync linux/bpf.h
Synchronize changes to linux/bpf.h from
* "bpf: allow zero-initializing hash map seed"
* "bpf: move BPF_F_QUERY_EFFECTIVE after map flags"

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-20 00:53:40 +01:00
Lorenz Bauer
2f1833607a bpf: move BPF_F_QUERY_EFFECTIVE after map flags
BPF_F_QUERY_EFFECTIVE is in the middle of the flags valid
for BPF_MAP_CREATE. Move it to its own section to reduce confusion.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-20 00:53:39 +01:00
Lorenz Bauer
96b3b6c909 bpf: allow zero-initializing hash map seed
Add a new flag BPF_F_ZERO_SEED, which forces a hash map
to initialize the seed to zero. This is useful when doing
performance analysis both on individual BPF programs, as
well as the kernel's hash table implementation.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-20 00:53:39 +01:00
Stanislav Fomichev
23499442c3 bpf: libbpf: retry map creation without the name
Since commit 88cda1c9da ("bpf: libbpf: Provide basic API support
to specify BPF obj name"), libbpf unconditionally sets bpf_attr->name
for maps. Pre v4.14 kernels don't know about map names and return an
error about unexpected non-zero data. Retry sys_bpf without a map
name to cover older kernels.

v2 changes:
* check for errno == EINVAL as suggested by Daniel Borkmann

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-20 00:49:32 +01:00
Colin Ian King
592ee43faf bpf: fix null pointer dereference on pointer offload
Pointer offload is being null checked however the following statement
dereferences the potentially null pointer offload when assigning
offload->dev_state.  Fix this by only assigning it if offload is not
null.

Detected by CoverityScan, CID#1475437 ("Dereference after null check")

Fixes: 00db12c3d1 ("bpf: call verifier_prep from its callback in struct bpf_offload_dev")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 20:48:27 -08:00
Stanislav Fomichev
29a9c10e41 bpftool: make libbfd optional
Make it possible to build bpftool without libbfd. libbfd and libopcodes are
typically provided in dev/dbg packages (binutils-dev in debian) which we
usually don't have installed on the fleet machines and we'd like a way to have
bpftool version that works without installing any additional packages.
This excludes support for disassembling jit-ted code and prints an error if
the user tries to use these features.

Tested by:
cat > FEATURES_DUMP.bpftool <<EOF
feature-libbfd=0
feature-disassembler-four-args=1
feature-reallocarray=0
feature-libelf=1
feature-libelf-mmap=1
feature-bpf=1
EOF
FEATURES_DUMP=$PWD/FEATURES_DUMP.bpftool make
ldd bpftool | grep libbfd

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 20:45:01 -08:00
Alexei Starovoitov
ae9435f696 Merge branch 'socket-lookup-cg_sock'
Andrey Ignatov says:

====================
This patch set makes bpf_sk_lookup_tcp, bpf_sk_lookup_udp and
bpf_sk_release helpers available in programs of type
BPF_PROG_TYPE_CGROUP_SOCK_ADDR.

Patch 1 is a fix for bpf_sk_lookup_udp that was already merged to bpf
(stable) tree. Here it's prerequisite for patch 3.

Patch 2 is the main patch in the set, it makes the helpers available for
BPF_PROG_TYPE_CGROUP_SOCK_ADDR and provides more details about use-case.

Patch 3 adds selftest for new functionality.

v1->v2:
- remove "Split bpf_sk_lookup" patch since it was already split by:
  commit c8123ead13 ("bpf: Extend the sk_lookup() helper to XDP
  hookpoint.");
- avoid unnecessary bpf_sock_addr_sk_lookup function.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:54:30 -08:00
Andrey Ignatov
9108e3a023 selftest/bpf: Use bpf_sk_lookup_{tcp, udp} in test_sock_addr
Use bpf_sk_lookup_tcp, bpf_sk_lookup_udp and bpf_sk_release helpers from
test_sock_addr programs to make sure they're available and can lookup
and release socket properly for IPv4/IPv4, TCP/UDP.

Reading from a few fields of returned struct bpf_sock is also tested.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:54:29 -08:00
Andrey Ignatov
6c49e65e0d bpf: Support socket lookup in CGROUP_SOCK_ADDR progs
Make bpf_sk_lookup_tcp, bpf_sk_lookup_udp and bpf_sk_release helpers
available in programs of type BPF_PROG_TYPE_CGROUP_SOCK_ADDR.

Such programs operate on sockets and have access to socket and struct
sockaddr passed by user to system calls such as sys_bind, sys_connect,
sys_sendmsg.

It's useful to be able to lookup other sockets from these programs.
E.g. sys_connect may lookup IP:port endpoint and if there is a server
socket bound to that endpoint ("server" can be defined by saddr & sport
being zero), redirect client connection to it by rewriting IP:port in
sockaddr passed to sys_connect.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:54:29 -08:00
Andrey Ignatov
cac6cc2f5a bpf: Fix IPv6 dport byte order in bpf_sk_lookup_udp
Lookup functions in sk_lookup have different expectations about byte
order of provided arguments.

Specifically __inet_lookup, __udp4_lib_lookup and __udp6_lib_lookup
expect dport to be in network byte order and do ntohs(dport) internally.

At the same time __inet6_lookup expects dport to be in host byte order
and correspondingly name the argument hnum.

sk_lookup works correctly with __inet_lookup, __udp4_lib_lookup and
__inet6_lookup with regard to dport. But in __udp6_lib_lookup case it
uses host instead of expected network byte order. It makes result
returned by bpf_sk_lookup_udp for IPv6 incorrect.

The patch fixes byte order of dport passed to __udp6_lib_lookup.

Originally sk_lookup properly handled UDPv6, but not TCPv6. 5ef0ae84f0
fixes TCPv6 but breaks UDPv6.

Fixes: 5ef0ae84f0 ("bpf: Fix IPv6 dport byte-order in bpf_sk_lookup")
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:54:29 -08:00
Nathan Chancellor
ac8acec991 bpf: Remove unused variable in nsim_bpf
Clang warns:

drivers/net/netdevsim/bpf.c:557:30: error: unused variable 'state'
[-Werror,-Wunused-variable]
        struct nsim_bpf_bound_prog *state;
                                    ^
1 error generated.

The declaration should have been removed in commit b07ade27e9 ("bpf:
pass translate() as a callback and remove its ndo_bpf subcommand").

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:51:13 -08:00
Martin KaFai Lau
a83d6e76a6 bpf: libbpf: Fix bpf_program__next() API
This patch restores the behavior in
commit eac7d84519 ("tools: libbpf: don't return '.text' as a program for multi-function programs")
such that bpf_program__next() does not return pseudo programs in ".text".

Fixes: 0c19a9fbc9 ("libbpf: cleanup after partial failure in bpf_object__pin")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:46:54 -08:00
Joe Stringer
5c86d2125b selftests/bpf: Fix uninitialized duration warning
Daniel Borkmann reports:

test_progs.c: In function ‘main’:
test_progs.c:81:3: warning: ‘duration’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   printf("%s:PASS:%s %d nsec\n", __func__, tag, duration);\
   ^~~~~~
test_progs.c:1706:8: note: ‘duration’ was declared here
  __u32 duration;
        ^~~~~~~~

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-16 17:40:10 -08:00
Alexei Starovoitov
407be8d03e Merge branch 'narrow-loads'
Andrey Ignatov says:

====================
This patch set adds support for narrow loads with offset > 0 to BPF
verifier.

Patch 1 provides more details and is the main patch in the set.
Patches 2 and 3 add new test cases to test_verifier and test_sock_addr
selftests.

v1->v2:
- fix -Wdeclaration-after-statement warning.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 22:30:00 -08:00
Andrey Ignatov
e7605475f5 selftests/bpf: Test narrow loads with off > 0 for bpf_sock_addr
Add more test cases for context bpf_sock_addr to test narrow loads with
offset > 0 for ctx->user_ip4 field (__u32):
* off=1, size=1;
* off=2, size=1;
* off=3, size=1;
* off=2, size=2.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 22:29:59 -08:00
Andrey Ignatov
6c2afb674d selftests/bpf: Test narrow loads with off > 0 in test_verifier
Test the following narrow loads in test_verifier for context __sk_buff:
* off=1, size=1 - ok;
* off=2, size=1 - ok;
* off=3, size=1 - ok;
* off=0, size=2 - ok;
* off=1, size=2 - fail;
* off=0, size=2 - ok;
* off=3, size=2 - fail.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 22:29:59 -08:00
Andrey Ignatov
46f53a65d2 bpf: Allow narrow loads with offset > 0
Currently BPF verifier allows narrow loads for a context field only with
offset zero. E.g. if there is a __u32 field then only the following
loads are permitted:
  * off=0, size=1 (narrow);
  * off=0, size=2 (narrow);
  * off=0, size=4 (full).

On the other hand LLVM can generate a load with offset different than
zero that make sense from program logic point of view, but verifier
doesn't accept it.

E.g. tools/testing/selftests/bpf/sendmsg4_prog.c has code:

  #define DST_IP4			0xC0A801FEU /* 192.168.1.254 */
  ...
  	if ((ctx->user_ip4 >> 24) == (bpf_htonl(DST_IP4) >> 24) &&

where ctx is struct bpf_sock_addr.

Some versions of LLVM can produce the following byte code for it:

       8:       71 12 07 00 00 00 00 00         r2 = *(u8 *)(r1 + 7)
       9:       67 02 00 00 18 00 00 00         r2 <<= 24
      10:       18 03 00 00 00 00 00 fe 00 00 00 00 00 00 00 00         r3 = 4261412864 ll
      12:       5d 32 07 00 00 00 00 00         if r2 != r3 goto +7 <LBB0_6>

where `*(u8 *)(r1 + 7)` means narrow load for ctx->user_ip4 with size=1
and offset=3 (7 - sizeof(ctx->user_family) = 3). This load is currently
rejected by verifier.

Verifier code that rejects such loads is in bpf_ctx_narrow_access_ok()
what means any is_valid_access implementation, that uses the function,
works this way, e.g. bpf_skb_is_valid_access() for __sk_buff or
sock_addr_is_valid_access() for bpf_sock_addr.

The patch makes such loads supported. Offset can be in [0; size_default)
but has to be multiple of load size. E.g. for __u32 field the following
loads are supported now:
  * off=0, size=1 (narrow);
  * off=1, size=1 (narrow);
  * off=2, size=1 (narrow);
  * off=3, size=1 (narrow);
  * off=0, size=2 (narrow);
  * off=2, size=2 (narrow);
  * off=0, size=4 (full).

Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 22:29:59 -08:00
Alexei Starovoitov
f2cbf95826 Merge branch 'bpftool-flow-dissector'
Stanislav Fomichev says:

====================
v5 changes:
* FILE -> PATH for load/loadall (can be either file or directory now)
* simpler implementation for __bpf_program__pin_name
* removed p_err for REQ_ARGS checks
* parse_atach_detach_args -> parse_attach_detach_args
* for -> while in bpf_object__pin_{programs,maps} recovery

v4 changes:
* addressed another round of comments/style issues from Jakub Kicinski &
  Quentin Monnet (thanks!)
* implemented bpf_object__pin_maps and bpf_object__pin_programs helpers and
  used them in bpf_program__pin
* added new pin_name to bpf_program so bpf_program__pin
  works with sections that contain '/'
* moved *loadall* command implementation into a separate patch
* added patch that implements *pinmaps* to pin maps when doing
  load/loadall

v3 changes:
* (maybe) better cleanup for partial failure in bpf_object__pin
* added special case in bpf_program__pin for programs with single
  instances

v2 changes:
* addressed comments/style issues from Jakub Kicinski & Quentin Monnet
* removed logic that populates jump table
* added cleanup for partial failure in bpf_object__pin

This patch series adds support for loading and attaching flow dissector
programs from the bpftool:

* first patch fixes flow dissector section name in the selftests (so
  libbpf auto-detection works)
* second patch adds proper cleanup to bpf_object__pin, parts of which are now
  being used to attach all flow dissector progs/maps
* third patch adds special case in bpf_program__pin for programs with
  single instances (we don't create <prog>/0 pin anymore, just <prog>)
* forth patch adds pin_name to the bpf_program struct
  which is now used as a pin name in bpf_program__pin et al
* fifth patch adds *loadall* command that pins all programs, not just
  the first one
* sixth patch adds *pinmaps* argument to load/loadall to let users pin
  all maps of the obj file
* seventh patch adds actual flow_dissector support to the bpftool and
  an example
====================

Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:58:12 -08:00
Stanislav Fomichev
092f089273 bpftool: support loading flow dissector
This commit adds support for loading/attaching/detaching flow
dissector program.

When `bpftool loadall` is called with a flow_dissector prog (i.e. when the
'type flow_dissector' argument is passed), we load and pin all programs.
User is responsible to construct the jump table for the tail calls.

The last argument of `bpftool attach` is made optional for this use
case.

Example:
bpftool prog load tools/testing/selftests/bpf/bpf_flow.o \
        /sys/fs/bpf/flow type flow_dissector \
	pinmaps /sys/fs/bpf/flow

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 0 0 0 0 \
        value pinned /sys/fs/bpf/flow/IP

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 1 0 0 0 \
        value pinned /sys/fs/bpf/flow/IPV6

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 2 0 0 0 \
        value pinned /sys/fs/bpf/flow/IPV6OP

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 3 0 0 0 \
        value pinned /sys/fs/bpf/flow/IPV6FR

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 4 0 0 0 \
        value pinned /sys/fs/bpf/flow/MPLS

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 5 0 0 0 \
        value pinned /sys/fs/bpf/flow/VLAN

bpftool prog attach pinned /sys/fs/bpf/flow/flow_dissector flow_dissector

Tested by using the above lines to load the prog in
the test_flow_dissector.sh selftest.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:11 -08:00
Stanislav Fomichev
3767a94b32 bpftool: add pinmaps argument to the load/loadall
This new additional argument lets users pin all maps from the object at
specified path.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:11 -08:00
Stanislav Fomichev
77380998d9 bpftool: add loadall command
This patch adds new *loadall* command which slightly differs from the
existing *load*. *load* command loads all programs from the obj file,
but pins only the first programs. *loadall* pins all programs from the
obj file under specified directory.

The intended usecase is flow_dissector, where we want to load a bunch
of progs, pin them all and after that construct a jump table.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:11 -08:00
Stanislav Fomichev
33a2c75c55 libbpf: add internal pin_name
pin_name is the same as section_name where '/' is replaced
by '_'. bpf_object__pin_programs is converted to use pin_name
to avoid the situation where section_name would require creating another
subdirectory for a pin (as, for example, when calling bpf_object__pin_programs
for programs in sections like "cgroup/connect6").

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:11 -08:00
Stanislav Fomichev
fd734c5cca libbpf: bpf_program__pin: add special case for instances.nr == 1
When bpf_program has only one instance, don't create a subdirectory with
per-instance pin files (<prog>/0). Instead, just create a single pin file
for that single instance. This simplifies object pinning by not creating
unnecessary subdirectories.

This can potentially break existing users that depend on the case
where '/0' is always created. However, I couldn't find any serious
usage of bpf_program__pin inside the kernel tree and I suppose there
should be none outside.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:10 -08:00
Stanislav Fomichev
0c19a9fbc9 libbpf: cleanup after partial failure in bpf_object__pin
bpftool will use bpf_object__pin in the next commits to pin all programs
and maps from the file; in case of a partial failure, we need to get
back to the clean state (undo previous program/map pins).

As part of a cleanup, I've added and exported separate routines to
pin all maps (bpf_object__pin_maps) and progs (bpf_object__pin_programs)
of an object.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:10 -08:00
Stanislav Fomichev
108d50a976 selftests/bpf: rename flow dissector section to flow_dissector
Makes it compatible with the logic that derives program type
from section name in libbpf_prog_type_by_name.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:56:10 -08:00
Alexei Starovoitov
0157edc859 Merge branch 'device-ops-as-cb'
Quentin Monnet says:

====================
For passing device functions for offloaded eBPF programs, there used to
be no place where to store the pointer without making the non-offloaded
programs pay a memory price.

As a consequence, three functions were called with ndo_bpf() through
specific commands. Now that we have struct bpf_offload_dev, and since none
of those operations rely on RTNL, we can turn these three commands into
hooks inside the struct bpf_prog_offload_ops, and pass them as part of
bpf_offload_dev_create().

This patch set changes the offload architecture to do so, and brings the
relevant changes to the nfp and netdevsim drivers.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:55 -08:00
Quentin Monnet
16a8cb5cff bpf: do not pass netdev to translate() and prepare() offload callbacks
The kernel functions to prepare verifier and translate for offloaded
program retrieve "offload" from "prog", and "netdev" from "offload".
Then both "prog" and "netdev" are passed to the callbacks.

Simplify this by letting the drivers retrieve the net device themselves
from the offload object attached to prog - if they need it at all. There
is currently no need to pass the netdev as an argument to those
functions.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:54 -08:00
Quentin Monnet
a40a26322a bpf: pass prog instead of env to bpf_prog_offload_verifier_prep()
Function bpf_prog_offload_verifier_prep(), called from the kernel BPF
verifier to run a driver-specific callback for preparing for the
verification step for offloaded programs, takes a pointer to a struct
bpf_verifier_env object. However, no driver callback needs the whole
structure at this time: the two drivers supporting this, nfp and
netdevsim, only need a pointer to the struct bpf_prog instance held by
env.

Update the callback accordingly, on kernel side and in these two
drivers.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:54 -08:00
Quentin Monnet
eb9119471e bpf: pass destroy() as a callback and remove its ndo_bpf subcommand
As part of the transition from ndo_bpf() to callbacks attached to struct
bpf_offload_dev for some of the eBPF offload operations, move the
functions related to program destruction to the struct and remove the
subcommand that was used to call them through the NDO.

Remove function __bpf_offload_ndo(), which is no longer used.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:54 -08:00
Quentin Monnet
b07ade27e9 bpf: pass translate() as a callback and remove its ndo_bpf subcommand
As part of the transition from ndo_bpf() to callbacks attached to struct
bpf_offload_dev for some of the eBPF offload operations, move the
functions related to code translation to the struct and remove the
subcommand that was used to call them through the NDO.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:54 -08:00
Quentin Monnet
00db12c3d1 bpf: call verifier_prep from its callback in struct bpf_offload_dev
In a way similar to the change previously brought to the verify_insn
hook and to the finalize callback, switch to the newly added ops in
struct bpf_prog_offload for calling the functions used to prepare driver
verifiers.

Since the dev_ops pointer in struct bpf_prog_offload is no longer used
by any callback, we can now remove it from struct bpf_prog_offload.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:54 -08:00
Quentin Monnet
6dc18fa6f4 bpf: call finalize() from its callback in struct bpf_offload_dev
In a way similar to the change previously brought to the verify_insn
hook, switch to the newly added ops in struct bpf_prog_offload for
calling the functions used to perform final verification steps for
offloaded programs.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:53 -08:00
Quentin Monnet
341b3e7b7b bpf: call verify_insn from its callback in struct bpf_offload_dev
We intend to remove the dev_ops in struct bpf_prog_offload, and to only
keep the ops in struct bpf_offload_dev instead, which is accessible from
more locations for passing function pointers.

But dev_ops is used for calling the verify_insn hook. Switch to the
newly added ops in struct bpf_prog_offload instead.

To avoid table lookups for each eBPF instruction to verify, we remember
the offdev attached to a netdev and modify bpf_offload_find_netdev() to
avoid performing more than once a lookup for a given offload object.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:53 -08:00
Quentin Monnet
1385d755cf bpf: pass a struct with offload callbacks to bpf_offload_dev_create()
For passing device functions for offloaded eBPF programs, there used to
be no place where to store the pointer without making the non-offloaded
programs pay a memory price.

As a consequence, three functions were called with ndo_bpf() through
specific commands. Now that we have struct bpf_offload_dev, and since
none of those operations rely on RTNL, we can turn these three commands
into hooks inside the struct bpf_prog_offload_ops, and pass them as part
of bpf_offload_dev_create().

This commit effectively passes a pointer to the struct to
bpf_offload_dev_create(). We temporarily have two struct
bpf_prog_offload_ops instances, one under offdev->ops and one under
offload->dev_ops. The next patches will make the transition towards the
former, so that offload->dev_ops can be removed, and callbacks relying
on ndo_bpf() added to offdev->ops as well.

While at it, rename "nfp_bpf_analyzer_ops" as "nfp_bpf_dev_ops" (and
similarly for netdevsim).

Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:53 -08:00
Quentin Monnet
1da6f57338 nfp: bpf: move nfp_bpf_analyzer_ops from verifier.c to offload.c
We are about to add several new callbacks to the struct, all of them
defined in offload.c. Move the struct bpf_prog_offload_ops object in
that file. As a consequence, nfp_verify_insn() and nfp_finalize() can no
longer be static.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-10 15:39:53 -08:00
Nitin Hande
c8123ead13 bpf: Extend the sk_lookup() helper to XDP hookpoint.
This patch proposes to extend the sk_lookup() BPF API to the
XDP hookpoint. The sk_lookup() helper supports a lookup
on incoming packet to find the corresponding socket that will
receive this packet. Current support for this BPF API is
at the tc hookpoint. This patch will extend this API at XDP
hookpoint. A XDP program can map the incoming packet to the
5-tuple parameter and invoke the API to find the corresponding
socket structure.

Signed-off-by: Nitin Hande <Nitin.Hande@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 10:14:54 +01:00
David Ahern
bf598a8f0f bpftool: Improve handling of ENOENT on map dumps
bpftool output is not user friendly when dumping a map with only a few
populated entries:

    $ bpftool map
    1: devmap  name tx_devmap  flags 0x0
            key 4B  value 4B  max_entries 64  memlock 4096B
    2: array  name tx_idxmap  flags 0x0
            key 4B  value 4B  max_entries 64  memlock 4096B

    $ bpftool map dump id 1
    key:
    00 00 00 00
    value:
    No such file or directory
    key:
    01 00 00 00
    value:
    No such file or directory
    key:
    02 00 00 00
    value:
    No such file or directory
    key: 03 00 00 00  value: 03 00 00 00

Handle ENOENT by keeping the line format sane and dumping
"<no entry>" for the value

    $ bpftool map dump id 1
    key: 00 00 00 00  value: <no entry>
    key: 01 00 00 00  value: <no entry>
    key: 02 00 00 00  value: <no entry>
    key: 03 00 00 00  value: 03 00 00 00
    ...

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 10:03:59 +01:00
Sowmini Varadhan
435f90a338 selftests/bpf: add a test case for sock_ops perf-event notification
This patch provides a tcp_bpf based eBPF sample. The test

- ncat(1) as the TCP client program to connect() to a port
  with the intention of triggerring SYN retransmissions: we
  first install an iptables DROP rule to make sure ncat SYNs are
  resent (instead of aborting instantly after a TCP RST)

- has a bpf kernel module that sends a perf-event notification for
  each TCP retransmit, and also tracks the number of such notifications
  sent in the global_map

The test passes when the number of event notifications intercepted
in user-space matches the value in the global_map.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 09:40:17 +01:00
Sowmini Varadhan
a5a3a828cd bpf: add perf event notificaton support for sock_ops
This patch allows eBPF programs that use sock_ops to send perf
based event notifications using bpf_perf_event_output(). Our main
use case for this is the following:

  We would like to monitor some subset of TCP sockets in user-space,
  (the monitoring application would define 4-tuples it wants to monitor)
  using TCP_INFO stats to analyze reported problems. The idea is to
  use those stats to see where the bottlenecks are likely to be ("is
  it application-limited?" or "is there evidence of BufferBloat in
  the path?" etc).

  Today we can do this by periodically polling for tcp_info, but this
  could be made more efficient if the kernel would asynchronously
  notify the application via tcp_info when some "interesting"
  thresholds (e.g., "RTT variance > X", or "total_retrans > Y" etc)
  are reached. And to make this effective, it is better if
  we could apply the threshold check *before* constructing the
  tcp_info netlink notification, so that we don't waste resources
  constructing notifications that will be discarded by the filter.

This work solves the problem by adding perf event based notification
support for sock_ops. The eBPF program can thus be designed to apply
any desired filters to the bpf_sock_ops and trigger a perf event
notification based on the evaluation from the filter. The user space
component can use these perf event notifications to either read any
state managed by the eBPF program, or issue a TCP_INFO netlink call
if desired.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 09:37:58 +01:00
Daniel Borkmann
185067a86a Merge branch 'bpf-max-pkt-offset'
Jiong Wang says:

====================
The maximum packet offset accessed by one BPF program is useful
information.

Because sometimes there could be packet split and it is possible for some
reasons (for example performance) we want to reject the BPF program if the
maximum packet size would trigger such split. Normally, MTU value is
treated as the maximum packet size, but one BPF program does not always
access the whole packet, it could only access the head portion of the data.

We could let verifier calculate the maximum packet offset ever used and
record it inside prog auxiliar information structure as a new field
"max_pkt_offset".
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 09:16:33 +01:00
Jiong Wang
cf599f5031 nfp: bpf: relax prog rejection through max_pkt_offset
NFP is refusing to offload programs whenever the MTU is set to a value
larger than the max packet bytes that fits in NFP Cluster Target Memory
(CTM). However, a eBPF program doesn't always need to access the whole
packet data.

Verifier has always calculated maximum direct packet access (DPA) offset,
and kept it in max_pkt_offset inside prog auxiliar information. This patch
relax prog rejection based on max_pkt_offset.

Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 09:16:32 +01:00
Jiong Wang
e647815a4d bpf: let verifier to calculate and record max_pkt_offset
In check_packet_access, update max_pkt_offset after the offset has passed
__check_packet_access.

It should be safe to use u32 for max_pkt_offset as explained in code
comment.

Also, when there is tail call, the max_pkt_offset of the called program is
unknown, so conservatively set max_pkt_offset to MAX_PACKET_OFF for such
case.

Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-09 09:16:31 +01:00
Shannon Nelson
bce6a14996 bpf_load: add map name to load_maps error message
To help when debugging bpf/xdp load issues, have the load_map()
error message include the number and name of the map that
failed.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-07 22:34:54 +01:00
Quentin Monnet
8302b9bd31 tools: bpftool: adjust rlimit RLIMIT_MEMLOCK when loading programs, maps
The limit for memory locked in the kernel by a process is usually set to
64 kbytes by default. This can be an issue when creating large BPF maps
and/or loading many programs. A workaround is to raise this limit for
the current process before trying to create a new BPF map. Changing the
hard limit requires the CAP_SYS_RESOURCE and can usually only be done by
root user (for non-root users, a call to setrlimit fails (and sets
errno) and the program simply goes on with its rlimit unchanged).

There is no API to get the current amount of memory locked for a user,
therefore we cannot raise the limit only when required. One solution,
used by bcc, is to try to create the map, and on getting a EPERM error,
raising the limit to infinity before giving another try. Another
approach, used in iproute2, is to raise the limit in all cases, before
trying to create the map.

Here we do the same as in iproute2: the rlimit is raised to infinity
before trying to load programs or to create maps with bpftool.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-07 22:22:21 +01:00
Quentin Monnet
f96afa767b selftests/bpf: enable (uncomment) all tests in test_libbpf.sh
libbpf is now able to load successfully test_l4lb_noinline.o and
samples/bpf/tracex3_kern.o.

For the test_l4lb_noinline, uncomment related tests from test_libbpf.c
and remove the associated "TODO".

For tracex3_kern.o, instead of loading a program from samples/bpf/ that
might not have been compiled at this stage, try loading a program from
BPF selftests. Since this test case is about loading a program compiled
without the "-target bpf" flag, change the Makefile to compile one
program accordingly (instead of passing the flag for compiling all
programs).

Regarding test_xdp_noinline.o: in its current shape the program fails to
load because it provides no version section, but the loader needs one.
The test was added to make sure that libbpf could load XDP programs even
if they do not provide a version number in a dedicated section. But
libbpf is already capable of doing that: in our case loading fails
because the loader does not know that this is an XDP program (it does
not need to, since it does not attach the program). So trying to load
test_xdp_noinline.o does not bring much here: just delete this subtest.

For the record, the error message obtained with tracex3_kern.o was
fixed by commit e3d91b0ca5 ("tools/libbpf: handle issues with bpf ELF
objects containing .eh_frames")

I have not been abled to reproduce the "libbpf: incorrect bpf_call
opcode" error for test_l4lb_noinline.o, even with the version of libbpf
present at the time when test_libbpf.sh and test_libbpf_open.c were
created.

RFC -> v1:
- Compile test_xdp without the "-target bpf" flag, and try to load it
  instead of ../../samples/bpf/tracex3_kern.o.
- Delete test_xdp_noinline.o subtest.

Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-07 22:20:56 +01:00
YueHaibing
f601a85bd7 net: hns3: Remove set but not used variable 'reset_level'
Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_err.c: In function 'hclge_log_and_clear_ppp_error':
drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_err.c:821:24: warning:
 variable 'reset_level' set but not used [-Wunused-but-set-variable]
  enum hnae3_reset_type reset_level = HNAE3_NONE_RESET;

It never used since introduction in commit
01865a50d7 ("net: hns3: Add enable and process hw errors of TM scheduler")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 11:46:37 -08:00