Add three tests to test_verifier/basic_instr that make sure that the
high 32-bits of the destination register is cleared after an ALU32
and/or/xor.
Signed-off-by: Björn Töpel <bjorn.topel@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The current method to compare 64-bit numbers for conditional jump is:
1) Compare the high 32-bit first.
2) If the high 32-bit isn't the same, then goto step 4.
3) Compare the low 32-bit.
4) Check the desired condition.
This method is right for unsigned comparison, but it is buggy for signed
comparison, because it does signed comparison for low 32-bit too.
There is only one sign bit in 64-bit number, that is the MSB in the 64-bit
number, it is wrong to treat low 32-bit as signed number and do the signed
comparison for it.
This patch fixes the bug and adds a testcase in selftests/bpf for such bug.
Signed-off-by: Wang YanQing <udknight@gmail.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>
This tests that:
* a BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE cannot be attached if it
uses either:
* a variable offset to the tracepoint buffer, or
* an offset beyond the size of the tracepoint buffer
* a tracer can modify the buffer provided when attached to a writable
tracepoint in bpf_prog_test_run
Signed-off-by: Matt Mullins <mmullins@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The first test case, for pointer null checks, is equivalent to the
following pseudo-code. It checks that the verifier does not complain on
line 6 and recognizes that ptr isn't null.
1: ptr = bpf_map_lookup_elem(map, &key);
2: ret = subprog(ptr) {
3: return ptr != NULL;
4: }
5: if (ret)
6: value = *ptr;
The second test case, for packet bound checks, is equivalent to the
following pseudo-code. It checks that the verifier does not complain on
line 7 and recognizes that the packet is at least 1 byte long.
1: pkt_end = ctx.pkt_end;
2: ptr = ctx.pkt + 8;
3: ret = subprog(ptr, pkt_end) {
4: return ptr <= pkt_end;
5: }
6: if (ret)
7: value = *(u8 *)ctx.pkt;
Signed-off-by: Paul Chaignon <paul.chaignon@orange.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>
Test that verifier handles new argument types properly, including
uninitialized or partially initialized value, misaligned stack access,
etc.
Example of output:
#456/p ARG_PTR_TO_LONG uninitialized OK
#457/p ARG_PTR_TO_LONG half-uninitialized OK
#458/p ARG_PTR_TO_LONG misaligned OK
#459/p ARG_PTR_TO_LONG size < sizeof(long) OK
#460/p ARG_PTR_TO_LONG initialized OK
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-04-12
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Improve BPF verifier scalability for large programs through two
optimizations: i) remove verifier states that are not useful in pruning,
ii) stop walking parentage chain once first LIVE_READ is seen. Combined
gives approx 20x speedup. Increase limits for accepting large programs
under root, and add various stress tests, from Alexei.
2) Implement global data support in BPF. This enables static global variables
for .data, .rodata and .bss sections to be properly handled which allows
for more natural program development. This also opens up the possibility
to optimize program workflow by compiling ELFs only once and later only
rewriting section data before reload, from Daniel and with test cases and
libbpf refactoring from Joe.
3) Add config option to generate BTF type info for vmlinux as part of the
kernel build process. DWARF debug info is converted via pahole to BTF.
Latter relies on libbpf and makes use of BTF deduplication algorithm which
results in 100x savings compared to DWARF data. Resulting .BTF section is
typically about 2MB in size, from Andrii.
4) Add BPF verifier support for stack access with variable offset from
helpers and add various test cases along with it, from Andrey.
5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header
so that L2 encapsulation can be used for tc tunnels, from Alan.
6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that
users can define a subset of allowed __sk_buff fields that get fed into
the test program, from Stanislav.
7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up
various UBSAN warnings in bpftool, from Yonghong.
8) Generate a pkg-config file for libbpf, from Luca.
9) Dump program's BTF id in bpftool, from Prashant.
10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP
program, from Magnus.
11) kallsyms related fixes for the case when symbols are not present in
BPF selftests and samples, from Daniel
====================
Signed-off-by: David S. Miller <davem@davemloft.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>
Minor comment merge conflict in mlx5.
Staging driver has a fixup due to the skb->xmit_more changes
in 'net-next', but was removed in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Test the case when reg->smax_value is too small/big and can overflow,
and separately min and max values outside of stack bounds.
Example of output:
# ./test_verifier
#856/p indirect variable-offset stack access, unbounded OK
#857/p indirect variable-offset stack access, max out of bound OK
#858/p indirect variable-offset stack access, min out of bound OK
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Test that verifier rejects indirect stack access with variable offset in
unprivileged mode and accepts same code in privileged mode.
Since pointer arithmetics is prohibited in unprivileged mode verifier
should reject the program even before it gets to helper call that uses
variable offset, at the time when that variable offset is trying to be
constructed.
Example of output:
# ./test_verifier
...
#859/u indirect variable-offset stack access, priv vs unpriv OK
#859/p indirect variable-offset stack access, priv vs unpriv OK
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Test that verifier rejects indirect access to uninitialized stack with
variable offset.
Example of output:
# ./test_verifier
...
#859/p indirect variable-offset stack access, uninitialized OK
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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>
Test different scenarios of indirect variable-offset stack access: out of
bound access (>0), min_off below initialized part of the stack,
max_off+size above initialized part of the stack, initialized stack.
Example of output:
...
#856/p indirect variable-offset stack access, out of bound OK
#857/p indirect variable-offset stack access, max_off+size > max_initialized OK
#858/p indirect variable-offset stack access, min_off < min_initialized OK
#859/p indirect variable-offset stack access, ok OK
...
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds a test case with an excessive number of call stack frames
in dead code.
Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Tested-by: Xiao Han <xiao.han@orange.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 7640ead939 ("bpf: verifier: make sure callees don't prune
with caller differences") connected up parentage chains of all
frames of the stack. It didn't, however, ensure propagate_liveness()
propagates all liveness information along those chains.
This means pruning happening in the callee may generate explored
states with incomplete liveness for the chains in lower frames
of the stack.
The included selftest is similar to the prior one from commit
7640ead939 ("bpf: verifier: make sure callees don't prune with
caller differences"), where callee would prune regardless of the
difference in r8 state.
Now we also initialize r9 to 0 or 1 based on a result from get_random().
r9 is never read so the walk with r9 = 0 gets pruned (correctly) after
the walk with r9 = 1 completes.
The selftest is so arranged that the pruning will happen in the
callee. Since callee does not propagate read marks of r8, the
explored state at the pruning point prior to the callee will
now ignore r8.
Propagate liveness on all frames of the stack when pruning.
Fixes: f4d7e40a5b ("bpf: introduce function calls (verification)")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make sure that returning a struct sock_common * reference invokes
the reference tracking machinery in the verifier.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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>
Adding verifier tests to ensure the ptr returned from bpf_tcp_sock() and
bpf_sk_fullsock() cannot be accessed after bpf_sk_release() is called.
A few of the tests are derived from a reproducer test by Lorenz Bauer.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Non-zero imm value in the second part of the ldimm64 instruction for
BPF_PSEUDO_MAP_FD is invalid, and thus must be rejected. The map fd
only ever sits in the first instructions' imm field. None of the BPF
loaders known to us are using it, so risk of regression is minimal.
For clarity and consistency, the few insn->{src_reg,imm} occurrences
are rewritten into insn[0].{src_reg,imm}. Add a test case to the BPF
selftest suite as well.
Fixes: 0246e64d9a ("bpf: handle pseudo BPF_LD_IMM64 insn")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add two additional tests for further asserting the
BPF_ALU_NON_POINTER logic with cases that were missed
previously.
Cc: Marek Majkowski <marek@cloudflare.com>
Cc: Arthur Fabre <afabre@cloudflare.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch tests accessing the skb->sk and the new helpers,
bpf_sk_fullsock and bpf_tcp_sock.
The errstr of some existing "reference tracking" tests is changed
with s/bpf_sock/sock/ and s/socket/sock/ where "sock" is from the
verifier's reg_type_str[].
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
RISC-V does, in-general, not have "efficient unaligned access". When
testing the RISC-V BPF JIT, some selftests failed in the verification
due to misaligned access. Annotate these tests with the
F_NEEDS_EFFICIENT_UNALIGNED_ACCESS flag.
Signed-off-by: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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>
We don't have this helper if the kernel was compiled without
CONFIG_BPF_EVENTS. Setting prog_type to BPF_PROG_TYPE_TRACEPOINT
let's verifier correctly skip this test based on the missing
prog_type support in the kernel.
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>
