Use BPF_F_TEST_STATE_FREQ flag to check that precision
tracking works as expected by comparing every step it takes.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Software event output is only enabled by a few prog types.
This test is to ensure that all supported types are enabled for
bpf_perf_event_output successfully.
Signed-off-by: Allan Zhang <allanzhang@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
test_verifier tests can specify single- and multi-runs tests. Internally
logic of handling them is duplicated. Get rid of it by making single run
retval/data specification to be a first run spec.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Cc: Krzesimir Nowak <krzesimir@kinvolk.io>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Make sure that wide stores are allowed at proper (aligned) addresses.
Note that user_ip6 is naturally aligned on 8-byte boundary, so
correct addresses are user_ip6[0] and user_ip6[2]. msg_src_ip6 is,
however, aligned on a 4-byte bondary, so only msg_src_ip6[1]
can be wide-stored.
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2019-06-19
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) new SO_REUSEPORT_DETACH_BPF setsocktopt, from Martin.
2) BTF based map definition, from Andrii.
3) support bpf_map_lookup_elem for xskmap, from Jonathan.
4) bounded loops and scalar precision logic in the verifier, from Alexei.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 107 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The previous libbpf patch allows user to specify "prog_flags" to bpf
program load APIs. To enable high 32-bit randomization for a test, we need
to set BPF_F_TEST_RND_HI32 in "prog_flags".
To enable such randomization for all tests, we need to make sure all places
are passing BPF_F_TEST_RND_HI32. Changing them one by one is not
convenient, also, it would be better if a test could be switched to
"normal" running mode without code change.
Given the program load APIs used across bpf selftests are mostly:
bpf_prog_load: load from file
bpf_load_program: load from raw insns
A test_stub.c is implemented for bpf seltests, it offers two functions for
testing purpose:
bpf_prog_test_load
bpf_test_load_program
The are the same as "bpf_prog_load" and "bpf_load_program", except they
also set BPF_F_TEST_RND_HI32. Given *_xattr functions are the APIs to
customize any "prog_flags", it makes little sense to put these two
functions into libbpf.
Then, the following CFLAGS are passed to compilations for host programs:
-Dbpf_prog_load=bpf_prog_test_load
-Dbpf_load_program=bpf_test_load_program
They migrate the used load APIs to the test version, hence enable high
32-bit randomization for these tests without changing source code.
Besides all these, there are several testcases are using
"bpf_prog_load_attr" directly, their call sites are updated to pass
BPF_F_TEST_RND_HI32.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
- bpf_fill_ld_abs_vlan_push_pop:
Prevent zext happens inside PUSH_CNT loop. This could happen because
of BPF_LD_ABS (32-bit def) + BPF_JMP (64-bit use), or BPF_LD_ABS +
EXIT (64-bit use of R0). So, change BPF_JMP to BPF_JMP32 and redefine
R0 at exit path to cut off the data-flow from inside the loop.
- bpf_fill_jump_around_ld_abs:
Jump range is limited to 16 bit. every ld_abs is replaced by 6 insns,
but on arches like arm, ppc etc, there will be one BPF_ZEXT inserted
to extend the error value of the inlined ld_abs sequence which then
contains 7 insns. so, set the dividend to 7 so the testcase could
work on all arches.
- bpf_fill_scale1/bpf_fill_scale2:
Both contains ~1M BPF_ALU32_IMM which will trigger ~1M insn patcher
call because of hi32 randomization later when BPF_F_TEST_RND_HI32 is
set for bpf selftests. Insn patcher is not efficient that 1M call to
it will hang computer. So , change to BPF_ALU64_IMM to avoid hi32
randomization.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adjust scale tests to check for new jmp sequence limit.
BPF_JGT had to be changed to BPF_JEQ because the verifier was
too smart. It tracked the known safe range of R0 values
and pruned the search earlier before hitting exact 8192 limit.
bpf_semi_rand_get() was too (un)?lucky.
k = 0; was missing in bpf_fill_scale2.
It was testing a bit shorter sequence of jumps than intended.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch adds verifier tests for the bpf_sk_storage:
1. ARG_PTR_TO_MAP_VALUE_OR_NULL
2. Map and helper compatibility (e.g. disallow bpf_map_loookup_elem)
It also takes this chance to remove the unused struct btf_raw_data
and uses the BTF encoding macros from "test_btf.h".
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
map_fds[16] is the last one index-ed by fixup_map_array_small.
Hence, the MAX_NR_MAPS should be 17 instead.
Fixes: fb2abb73e5 ("bpf, selftest: test {rd, wr}only flags and direct value access")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add two tests to check that sequence of 1024 jumps is verifiable.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Extend test_verifier with various test cases around the two kernel
extensions, that is, {rd,wr}only map support as well as direct map
value access. All passing, one skipped due to xskmap not present
on test machine:
# ./test_verifier
[...]
#948/p XDP pkt read, pkt_meta' <= pkt_data, bad access 1 OK
#949/p XDP pkt read, pkt_meta' <= pkt_data, bad access 2 OK
#950/p XDP pkt read, pkt_data <= pkt_meta', good access OK
#951/p XDP pkt read, pkt_data <= pkt_meta', bad access 1 OK
#952/p XDP pkt read, pkt_data <= pkt_meta', bad access 2 OK
Summary: 1410 PASSED, 1 SKIPPED, 0 FAILED
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a test to generate 1m ld_imm64 insns to stress the verifier.
Bump the size of fill_ld_abs_vlan_push_pop test from 4k to 29k
and jump_around_ld_abs from 4k to 5.5k.
Larger sizes are not possible due to 16-bit offset encoding
in jump instructions.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Make the BPF_SK_LOOKUP macro take a helper function, to ease
writing tests for new helpers.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
add bpf_spin_lock tests to test_verifier.c that don't require
latest llvm with BTF support
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Use recently introduced bpf_probe_map_type() to skip tests in the
test_verifier if map creation (create_map) fails. It's handled
explicitly for each fixup, i.e. if bpf_create_map returns negative fd,
we probe the kernel for the appropriate map support and skip the
test is map type is not supported.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Use recently introduced bpf_probe_prog_type() to skip tests in the
test_verifier() if bpf_verify_program() fails. The skipped test is
indicated in the output.
Example:
...
679/p bpf_get_stack return R0 within range SKIP (unsupported program
type 5)
680/p ld_abs: invalid op 1 OK
...
Summary: 863 PASSED, 165 SKIPPED, 3 FAILED
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Break up the rest of test_verifier tests into separate
files.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Break up the first 10 kLoC of test verifier test cases
out into smaller files. Looks like git line counting
gets a little flismy above 16 bit integers, so we need
two commits to break up test_verifier.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
test_verifier.c has grown to be very long (almost 16 kLoC),
and it is very conflict prone since we always add tests at
the end.
Try to break it apart a little bit. Allow test snippets
to be defined in separate files and include them automatically
into the huge test array.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds unit tests for new JMP32 instructions.
This patch also added the new BPF_JMP32_REG and BPF_JMP32_IMM macros to
samples/bpf/bpf_insn.h so that JMP32 insn builders are available to tests
under 'samples' directory.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This adds the ability to read gso_segs from a BPF program.
v3: Use BPF_REG_AX instead of BPF_REG_TMP for the temporary register,
as suggested by Martin.
v2: refined Eddie Hao patch to address Alexei feedback.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eddie Hao <eddieh@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add tests for newly added dead code elimination. Both verifier
and BTF tests are added. BTF test infrastructure has to be
extended to be able to account for line info which is eliminated
during dead code removal.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add couple of test_verifier tests to check sanitation of alu op insn
with pointer and scalar type coming from different paths. This also
includes BPF insns of the test reproducer provided by Jann Horn.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add various map value pointer related test cases to test_verifier
kselftest to reflect recent changes and improve test coverage. The
tests include basic masking functionality, unprivileged behavior
on pointer arithmetic which goes oob, mixed bounds tests, negative
unknown scalar but resulting positive offset for access and helper
range, handling of arithmetic from multiple maps, various masking
scenarios with subsequent map value access and others including two
test cases from Jann Horn for prior fixes.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Minor fallout from merge resolution, test_verifier was segfaulting
because the REJECT result was correct, but errstr was NULL. Properly
fix it as in 339bbff2d6.
Fixes: 339bbff2d6 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-12-21
The following pull-request contains BPF updates for your *net-next* tree.
There is a merge conflict in test_verifier.c. Result looks as follows:
[...]
},
{
"calls: cross frame pruning",
.insns = {
[...]
.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
.errstr_unpriv = "function calls to other bpf functions are allowed for root only",
.result_unpriv = REJECT,
.errstr = "!read_ok",
.result = REJECT,
},
{
"jset: functional",
.insns = {
[...]
{
"jset: unknown const compare not taken",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_prandom_u32),
BPF_JMP_IMM(BPF_JSET, BPF_REG_0, 1, 1),
BPF_LDX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
.errstr_unpriv = "!read_ok",
.result_unpriv = REJECT,
.errstr = "!read_ok",
.result = REJECT,
},
[...]
{
"jset: range",
.insns = {
[...]
},
.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
.result_unpriv = ACCEPT,
.result = ACCEPT,
},
The main changes are:
1) Various BTF related improvements in order to get line info
working. Meaning, verifier will now annotate the corresponding
BPF C code to the error log, from Martin and Yonghong.
2) Implement support for raw BPF tracepoints in modules, from Matt.
3) Add several improvements to verifier state logic, namely speeding
up stacksafe check, optimizations for stack state equivalence
test and safety checks for liveness analysis, from Alexei.
4) Teach verifier to make use of BPF_JSET instruction, add several
test cases to kselftests and remove nfp specific JSET optimization
now that verifier has awareness, from Jakub.
5) Improve BPF verifier's slot_type marking logic in order to
allow more stack slot sharing, from Jiong.
6) Add sk_msg->size member for context access and add set of fixes
and improvements to make sock_map with kTLS usable with openssl
based applications, from John.
7) Several cleanups and documentation updates in bpftool as well as
auto-mount of tracefs for "bpftool prog tracelog" command,
from Quentin.
8) Include sub-program tags from now on in bpf_prog_info in order to
have a reliable way for user space to get all tags of the program
e.g. needed for kallsyms correlation, from Song.
9) Add BTF annotations for cgroup_local_storage BPF maps and
implement bpf fs pretty print support, from Roman.
10) Fix bpftool in order to allow for cross-compilation, from Ivan.
11) Update of bpftool license to GPLv2-only + BSD-2-Clause in order
to be compatible with libbfd and allow for Debian packaging,
from Jakub.
12) Remove an obsolete prog->aux sanitation in dump and get rid of
version check for prog load, from Daniel.
13) Fix a memory leak in libbpf's line info handling, from Prashant.
14) Fix cpumap's frame alignment for build_skb() so that skb_shared_info
does not get unaligned, from Jesper.
15) Fix test_progs kselftest to work with older compilers which are less
smart in optimizing (and thus throwing build error), from Stanislav.
16) Cleanup and simplify AF_XDP socket teardown, from Björn.
17) Fix sk lookup in BPF kselftest's test_sock_addr with regards
to netns_id argument, from Andrey.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the test to ensure reads past the end of the sk_msg_md
data structure fail is incorrectly expecting success. Fix this
typo and use correct expected error.
Fixes: 945a47d87c ("bpf: sk_msg, add tests for size field")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Lots of conflicts, by happily all cases of overlapping
changes, parallel adds, things of that nature.
Thanks to Stephen Rothwell, Saeed Mahameed, and others
for their guidance in these resolutions.
Signed-off-by: David S. Miller <davem@davemloft.net>
Validate that the verifier reasons correctly about the bounds
and removes dead code based on results of JSET instruction.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
We seem to have no JSET instruction test, and LLVM does not
generate it at all, so let's add a simple hand-coded test
to make sure JIT implementations are correct.
v2:
- extend test_verifier to handle multiple inputs and
add the sample there (Daniel)
- add a sign extension case
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This adds tests to read the size field to test_verifier.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Verifier is supposed to support sharing stack slot allocated to ptr with
SCALAR_VALUE for privileged program. However this doesn't happen for some
cases.
The reason is verifier is not clearing slot_type STACK_SPILL for all bytes,
it only clears part of them, while verifier is using:
slot_type[0] == STACK_SPILL
as a convention to check one slot is ptr type.
So, the consequence of partial clearing slot_type is verifier could treat a
partially overridden ptr slot, which should now be a SCALAR_VALUE slot,
still as ptr slot, and rejects some valid programs.
Before this patch, test_xdp_noinline.o under bpf selftests, bpf_lxc.o and
bpf_netdev.o under Cilium bpf repo, when built with -mattr=+alu32 are
rejected due to this issue. After this patch, they all accepted.
There is no processed insn number change before and after this patch on
Cilium bpf programs.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
"if (old->allocated_stack > cur->allocated_stack)" check is too conservative.
In some cases explored stack could have allocated more space,
but that stack space was not live.
The test case improves from 19 to 15 processed insns
and improvement on real programs is significant as well:
before after
bpf_lb-DLB_L3.o 1940 1831
bpf_lb-DLB_L4.o 3089 3029
bpf_lb-DUNKNOWN.o 1065 1064
bpf_lxc-DDROP_ALL.o 28052 26309
bpf_lxc-DUNKNOWN.o 35487 33517
bpf_netdev.o 10864 9713
bpf_overlay.o 6643 6184
bpf_lcx_jit.o 38437 37335
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Edward Cree <ecree@solarflare.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Teach test_verifier to parse verifier output for insn processed
and compare with expected number.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Edward Cree <ecree@solarflare.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently for liveness and state pruning the register parentage
chains don't include states of the callee. This makes some sense
as the callee can't access those registers. However, this means
that READs done after the callee returns will not propagate into
the states of the callee. Callee will then perform pruning
disregarding differences in caller state.
Example:
0: (85) call bpf_user_rnd_u32
1: (b7) r8 = 0
2: (55) if r0 != 0x0 goto pc+1
3: (b7) r8 = 1
4: (bf) r1 = r8
5: (85) call pc+4
6: (15) if r8 == 0x1 goto pc+1
7: (05) *(u64 *)(r9 - 8) = r3
8: (b7) r0 = 0
9: (95) exit
10: (15) if r1 == 0x0 goto pc+0
11: (95) exit
Here we acquire unknown state with call to get_random() [1]. Then
we store this random state in r8 (either 0 or 1) [1 - 3], and make
a call on line 5. Callee does nothing but a trivial conditional
jump (to create a pruning point). Upon return caller checks the
state of r8 and either performs an unsafe read or not.
Verifier will first explore the path with r8 == 1, creating a pruning
point at [11]. The parentage chain for r8 will include only callers
states so once verifier reaches [6] it will mark liveness only on states
in the caller, and not [11]. Now when verifier walks the paths with
r8 == 0 it will reach [11] and since REG_LIVE_READ on r8 was not
propagated there it will prune the walk entirely (stop walking
the entire program, not just the callee). Since [6] was never walked
with r8 == 0, [7] will be considered dead and replaced with "goto -1"
causing hang at runtime.
This patch weaves the callee's explored states onto the callers
parentage chain. Rough parentage for r8 would have looked like this
before:
[0] [1] [2] [3] [4] [5] [10] [11] [6] [7]
| | ,---|----. | | |
sl0: sl0: / sl0: \ sl0: sl0: sl0:
fr0: r8 <-- fr0: r8<+--fr0: r8 `fr0: r8 ,fr0: r8<-fr0: r8
\ fr1: r8 <- fr1: r8 /
\__________________/
after:
[0] [1] [2] [3] [4] [5] [10] [11] [6] [7]
| | | | | |
sl0: sl0: sl0: sl0: sl0: sl0:
fr0: r8 <-- fr0: r8 <- fr0: r8 <- fr0: r8 <-fr0: r8<-fr0: r8
fr1: r8 <- fr1: r8
Now the mark from instruction 6 will travel through callees states.
Note that we don't have to connect r0 because its overwritten by
callees state on return and r1 - r5 because those are not alive
any more once a call is made.
v2:
- don't connect the callees registers twice (Alexei: suggestion & code)
- add more details to the comment (Ed & Alexei)
v1: don't unnecessarily link caller saved regs (Jiong)
Fixes: f4d7e40a5b ("bpf: introduce function calls (verification)")
Reported-by: David Beckett <david.beckett@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-12-11
The following pull-request contains BPF updates for your *net-next* tree.
It has three minor merge conflicts, resolutions:
1) tools/testing/selftests/bpf/test_verifier.c
Take first chunk with alignment_prevented_execution.
2) net/core/filter.c
[...]
case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
case bpf_ctx_range(struct __sk_buff, wire_len):
return false;
[...]
3) include/uapi/linux/bpf.h
Take the second chunk for the two cases each.
The main changes are:
1) Add support for BPF line info via BTF and extend libbpf as well
as bpftool's program dump to annotate output with BPF C code to
facilitate debugging and introspection, from Martin.
2) Add support for BPF_ALU | BPF_ARSH | BPF_{K,X} in interpreter
and all JIT backends, from Jiong.
3) Improve BPF test coverage on archs with no efficient unaligned
access by adding an "any alignment" flag to the BPF program load
to forcefully disable verifier alignment checks, from David.
4) Add a new bpf_prog_test_run_xattr() API to libbpf which allows for
proper use of BPF_PROG_TEST_RUN with data_out, from Lorenz.
5) Extend tc BPF programs to use a new __sk_buff field called wire_len
for more accurate accounting of packets going to wire, from Petar.
6) Improve bpftool to allow dumping the trace pipe from it and add
several improvements in bash completion and map/prog dump,
from Quentin.
7) Optimize arm64 BPF JIT to always emit movn/movk/movk sequence for
kernel addresses and add a dedicated BPF JIT backend allocator,
from Ard.
8) Add a BPF helper function for IR remotes to report mouse movements,
from Sean.
9) Various cleanups in BPF prog dump e.g. to make UAPI bpf_prog_info
member naming consistent with existing conventions, from Yonghong
and Song.
10) Misc cleanups and improvements in allowing to pass interface name
via cmdline for xdp1 BPF example, from Matteo.
11) Fix a potential segfault in BPF sample loader's kprobes handling,
from Daniel T.
12) Fix SPDX license in libbpf's README.rst, from Andrey.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use bpf_prog_type instead of bpf_map_type when passing prog_type.
-Wenum-conversion might be unhappy about it:
error: implicit conversion from enumeration type
'enum bpf_map_type' to different enumeration type
'enum bpf_prog_type'
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
I get a segfault without it, other fixups always do dereference, and
without dereference I don't understand how it can ever work.
Fixes: 7c85c448e7 ("selftests/bpf: test_verifier, check bpf_map_lookup_elem access in bpf prog")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, the destination register is marked as unknown for 32-bit
sub-register move (BPF_MOV | BPF_ALU) whenever the source register type is
SCALAR_VALUE.
This is too conservative that some valid cases will be rejected.
Especially, this may turn a constant scalar value into unknown value that
could break some assumptions of verifier.
For example, test_l4lb_noinline.c has the following C code:
struct real_definition *dst
1: if (!get_packet_dst(&dst, &pckt, vip_info, is_ipv6))
2: return TC_ACT_SHOT;
3:
4: if (dst->flags & F_IPV6) {
get_packet_dst is responsible for initializing "dst" into valid pointer and
return true (1), otherwise return false (0). The compiled instruction
sequence using alu32 will be:
412: (54) (u32) r7 &= (u32) 1
413: (bc) (u32) r0 = (u32) r7
414: (95) exit
insn 413, a BPF_MOV | BPF_ALU, however will turn r0 into unknown value even
r7 contains SCALAR_VALUE 1.
This causes trouble when verifier is walking the code path that hasn't
initialized "dst" inside get_packet_dst, for which case 0 is returned and
we would then expect verifier concluding line 1 in the above C code pass
the "if" check, therefore would skip fall through path starting at line 4.
Now, because r0 returned from callee has became unknown value, so verifier
won't skip analyzing path starting at line 4 and "dst->flags" requires
dereferencing the pointer "dst" which actually hasn't be initialized for
this path.
This patch relaxed the code marking sub-register move destination. For a
SCALAR_VALUE, it is safe to just copy the value from source then truncate
it into 32-bit.
A unit test also included to demonstrate this issue. This test will fail
before this patch.
This relaxation could let verifier skipping more paths for conditional
comparison against immediate. It also let verifier recording a more
accurate/strict value for one register at one state, if this state end up
with going through exit without rejection and it is used for state
comparison later, then it is possible an inaccurate/permissive value is
better. So the real impact on verifier processed insn number is complex.
But in all, without this fix, valid program could be rejected.
>From real benchmarking on kernel selftests and Cilium bpf tests, there is
no impact on processed instruction number when tests ares compiled with
default compilation options. There is slightly improvements when they are
compiled with -mattr=+alu32 after this patch.
Also, test_xdp_noinline/-mattr=+alu32 now passed verification. It is
rejected before this fix.
Insn processed before/after this patch:
default -mattr=+alu32
Kernel selftest
===
test_xdp.o 371/371 369/369
test_l4lb.o 6345/6345 5623/5623
test_xdp_noinline.o 2971/2971 rejected/2727
test_tcp_estates.o 429/429 430/430
Cilium bpf
===
bpf_lb-DLB_L3.o: 2085/2085 1685/1687
bpf_lb-DLB_L4.o: 2287/2287 1986/1982
bpf_lb-DUNKNOWN.o: 690/690 622/622
bpf_lxc.o: 95033/95033 N/A
bpf_netdev.o: 7245/7245 N/A
bpf_overlay.o: 2898/2898 3085/2947
NOTE:
- bpf_lxc.o and bpf_netdev.o compiled by -mattr=+alu32 are rejected by
verifier due to another issue inside verifier on supporting alu32
binary.
- Each cilium bpf program could generate several processed insn number,
above number is sum of them.
v1->v2:
- Restrict the change on SCALAR_VALUE.
- Update benchmark numbers on Cilium bpf tests.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Several conflicts, seemingly all over the place.
I used Stephen Rothwell's sample resolutions for many of these, if not
just to double check my own work, so definitely the credit largely
goes to him.
The NFP conflict consisted of a bug fix (moving operations
past the rhashtable operation) while chaning the initial
argument in the function call in the moved code.
The net/dsa/master.c conflict had to do with a bug fix intermixing of
making dsa_master_set_mtu() static with the fixing of the tagging
attribute location.
cls_flower had a conflict because the dup reject fix from Or
overlapped with the addition of port range classifiction.
__set_phy_supported()'s conflict was relatively easy to resolve
because Andrew fixed it in both trees, so it was just a matter
of taking the net-next copy. Or at least I think it was :-)
Joe Stringer's fix to the handling of netns id 0 in bpf_sk_lookup()
intermixed with changes on how the sdif and caller_net are calculated
in these code paths in net-next.
The remaining BPF conflicts were largely about the addition of the
__bpf_md_ptr stuff in 'net' overlapping with adjustments and additions
to the relevant data structure where the MD pointer macros are used.
Signed-off-by: David S. Miller <davem@davemloft.net>
"arsh32 on imm" and "arsh32 on reg" now are accepted. Also added two new
testcases to make sure arsh32 won't be treated as arsh64 during
interpretation or JIT code-gen for which case the high bits will be moved
into low halve that the testcases could catch them.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
pathological bpf programs may try to force verifier to explode in
the number of branch states:
20: (d5) if r1 s<= 0x24000028 goto pc+0
21: (b5) if r0 <= 0xe1fa20 goto pc+2
22: (d5) if r1 s<= 0x7e goto pc+0
23: (b5) if r0 <= 0xe880e000 goto pc+0
24: (c5) if r0 s< 0x2100ecf4 goto pc+0
25: (d5) if r1 s<= 0xe880e000 goto pc+1
26: (c5) if r0 s< 0xf4041810 goto pc+0
27: (d5) if r1 s<= 0x1e007e goto pc+0
28: (b5) if r0 <= 0xe86be000 goto pc+0
29: (07) r0 += 16614
30: (c5) if r0 s< 0x6d0020da goto pc+0
31: (35) if r0 >= 0x2100ecf4 goto pc+0
Teach verifier to recognize always taken and always not taken branches.
This analysis is already done for == and != comparison.
Expand it to all other branches.
It also helps real bpf programs to be verified faster:
before after
bpf_lb-DLB_L3.o 2003 1940
bpf_lb-DLB_L4.o 3173 3089
bpf_lb-DUNKNOWN.o 1080 1065
bpf_lxc-DDROP_ALL.o 29584 28052
bpf_lxc-DUNKNOWN.o 36916 35487
bpf_netdev.o 11188 10864
bpf_overlay.o 6679 6643
bpf_lcx_jit.o 39555 38437
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The pkt_len field in qdisc_skb_cb stores the skb length as it will
appear on the wire after segmentation. For byte accounting, this value
is more accurate than skb->len. It is computed on entry to the TC
layer, so only valid there.
Allow read access to this field from BPF tc classifier and action
programs. The implementation is analogous to tc_classid, aside from
restricting to read access.
To distinguish it from skb->len and self-describe export as wire_len.
Changes v1->v2
- Rename pkt_len to wire_len
Signed-off-by: Petar Penkov <ppenkov@google.com>
Signed-off-by: Vlad Dumitrescu <vladum@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
If a testcase has alignment problems but is expected to be ACCEPT,
verify it using F_NEEDS_EFFICIENT_UNALIGNED_ACCESS too.
Maybe in the future if we add some architecture specific code to elide
the unaligned memory access warnings during the test, we can execute
these as well.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Use F_NEEDS_EFFICIENT_UNALIGNED_ACCESS in more tests where the
expected result is REJECT.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make it set the flag argument to bpf_verify_program() which will relax
the alignment restrictions.
Now all such test cases will go properly through the verifier even on
inefficient unaligned access architectures.
On inefficient unaligned access architectures do not try to run such
programs, instead mark the test case as passing but annotate the
result similarly to how it is done now in the presence of this flag.
So, we get complete full coverage for all REJECT test cases, and at
least verifier level coverage for ACCEPT test cases.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Alexei Starovoitov