Commit graph

2901 commits

Author SHA1 Message Date
Eduard Zingerman
05e474ecbb selftests/bpf: verifier/map_ret_val.c converted to inline assembly
Test verifier/map_ret_val.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-29-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:05 -07:00
Eduard Zingerman
caf345cf12 selftests/bpf: verifier/map_ptr.c converted to inline assembly
Test verifier/map_ptr.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-28-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
583c7ce5be selftests/bpf: verifier/leak_ptr.c converted to inline assembly
Test verifier/leak_ptr.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-27-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
e297875580 selftests/bpf: verifier/ld_ind.c converted to inline assembly
Test verifier/ld_ind.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-26-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
01481e67dd selftests/bpf: verifier/int_ptr.c converted to inline assembly
Test verifier/int_ptr.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-25-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
ecc424827b selftests/bpf: verifier/helper_value_access.c converted to inline assembly
Test verifier/helper_value_access.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-24-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
77aa2563cb selftests/bpf: verifier/helper_restricted.c converted to inline assembly
Test verifier/helper_restricted.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-23-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
fb179fe69e selftests/bpf: verifier/helper_packet_access.c converted to inline assembly
Test verifier/helper_packet_access.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-22-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
b37d776b43 selftests/bpf: verifier/helper_access_var_len.c converted to inline assembly
Test verifier/helper_access_var_len.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-21-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
9553de70a8 selftests/bpf: verifier/div_overflow.c converted to inline assembly
Test verifier/div_overflow.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-20-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
01a0925531 selftests/bpf: verifier/div0.c converted to inline assembly
Test verifier/div0.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-19-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:04 -07:00
Eduard Zingerman
84988478fb selftests/bpf: verifier/direct_stack_access_wraparound.c converted to inline assembly
Test verifier/direct_stack_access_wraparound.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-18-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
a58475a989 selftests/bpf: verifier/ctx_sk_msg.c converted to inline assembly
Test verifier/ctx_sk_msg.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-17-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
a2777eaad5 selftests/bpf: verifier/const_or.c converted to inline assembly
Test verifier/const_or.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-16-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
8f16f3c07e selftests/bpf: verifier/cgroup_storage.c converted to inline assembly
Test verifier/cgroup_storage.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-15-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
b1b6372535 selftests/bpf: verifier/cgroup_skb.c converted to inline assembly
Test verifier/cgroup_skb.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-14-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
047687a7f4 selftests/bpf: verifier/cgroup_inv_retcode.c converted to inline assembly
Test verifier/cgroup_inv_retcode.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-13-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
2f2047c22c selftests/bpf: verifier/cfg.c converted to inline assembly
Test verifier/cfg.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-12-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
b14a702afd selftests/bpf: verifier/bounds_mix_sign_unsign.c converted to inline assembly
Test verifier/bounds_mix_sign_unsign.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-11-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
7605f94b34 selftests/bpf: verifier/bounds_deduction.c converted to inline assembly
Test verifier/bounds_deduction.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-10-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:03 -07:00
Eduard Zingerman
0ccbe4956d selftests/bpf: verifier/basic_stack.c converted to inline assembly
Test verifier/basic_stack.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-9-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
a3c830ae02 selftests/bpf: verifier/array_access.c converted to inline assembly
Test verifier/array_access.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-8-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
9d0f1568ad selftests/bpf: verifier/and.c converted to inline assembly
Test verifier/and.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
55108621a3 selftests/bpf: prog_tests entry point for migrated test_verifier tests
prog_tests/verifier.c would be used as a host for verifier/*.c tests
migrated to use inline assembly and run from test_progs.

The run_test_aux() function mimics the test_verifier behavior
dropping CAP_SYS_ADMIN upon entry.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-6-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
19a8e06f5f selftests/bpf: Tests execution support for test_loader.c
Extends test_loader.c:test_loader__run_subtests() by allowing to
execute BPF_PROG_TEST_RUN bpf command for selected programs.
This is similar to functionality provided by test_verifier.

Adds the following new attributes controlling test_loader behavior:

  __retval(...)
  __retval_unpriv(...)

* If any of these attributes is present, the annotated program would
  be executed using libbpf's bpf_prog_test_run_opts() function.
* If __retval is present, the test run would be done for program
  loaded in privileged mode.
* If __retval_unpriv is present, the test run would be done for
  program loaded in unprivileged mode.
* To mimic test_verifier behavior, the actual run is initiated in
  privileged mode.
* The value returned by a test run is compared against retval
  parameter.

The retval attribute takes one of the following parameters:
- a decimal number
- a hexadecimal number (must start from '0x')
- any of a three special literals (provided for compatibility with
  test_verifier):
  - INT_MIN
  - POINTER_VALUE
  - TEST_DATA_LEN

An example of the attribute usage:

  SEC("socket")
  __description("return 42")
  __success __success_unpriv __retval(42)
  __naked void the_42_test(void)
  {
          asm volatile ("                                 \
          r0 = 42;                                        \
          exit;                                           \
  "       ::: __clobber_all);
  }

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-5-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
1d56ade032 selftests/bpf: Unprivileged tests for test_loader.c
Extends test_loader.c:test_loader__run_subtests() by allowing to
execute tests in unprivileged mode, similar to test_verifier.c.

Adds the following new attributes controlling test_loader behavior:

  __msg_unpriv
  __success_unpriv
  __failure_unpriv

* If any of these attributes is present the test would be loaded in
  unprivileged mode.
* If only "privileged" attributes are present the test would be loaded
  only in privileged mode.
* If both "privileged" and "unprivileged" attributes are present the
  test would be loaded in both modes.
* If test has to be executed in both modes, __msg(text) is specified
  and __msg_unpriv is not specified the behavior is the same as if
  __msg_unpriv(text) is specified.
* For test filtering purposes the name of the program loaded in
  unprivileged mode is derived from the usual program name by adding
  `@unpriv' suffix.

Also adds attribute '__description'. This attribute specifies text to
be used instead of a program name for display and filtering purposes.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
207b1ba301 selftests/bpf: __imm_insn & __imm_const macro for bpf_misc.h
Add two convenience macro for BPF test cases,
allowing the following usage:

  #include <linux/filter.h>

  ...
  asm volatile (
  ...
  ".8byte %[raw_insn];"
  ...
  "r1 += %[st_foo_offset];"
  ...
  :
  : __imm_insn(raw_insn, BPF_RAW_INSN(...)),
    __imm_const(st_foo_offset, offsetof(struct st, foo))
  : __clobber_all);

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
Eduard Zingerman
3e5329e193 selftests/bpf: Report program name on parse_test_spec error
Change test_loader.c:run_subtest() behavior to show BPF program name
when test spec for that program can't be parsed.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 17:02:02 -07:00
David Vernet
6c831c4684 bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGS
KF_RELEASE kfuncs are not currently treated as having KF_TRUSTED_ARGS,
even though they have a superset of the requirements of KF_TRUSTED_ARGS.
Like KF_TRUSTED_ARGS, KF_RELEASE kfuncs require a 0-offset argument, and
don't allow NULL-able arguments. Unlike KF_TRUSTED_ARGS which require
_either_ an argument with ref_obj_id > 0, _or_ (ref->type &
BPF_REG_TRUSTED_MODIFIERS) (and no unsafe modifiers allowed), KF_RELEASE
only allows for ref_obj_id > 0.  Because KF_RELEASE today doesn't
automatically imply KF_TRUSTED_ARGS, some of these requirements are
enforced in different ways that can make the behavior of the verifier
feel unpredictable. For example, a KF_RELEASE kfunc with a NULL-able
argument will currently fail in the verifier with a message like, "arg#0
is ptr_or_null_ expected ptr_ or socket" rather than "Possibly NULL
pointer passed to trusted arg0". Our intention is the same, but the
semantics are different due to implemenetation details that kfunc authors
and BPF program writers should not need to care about.

Let's make the behavior of the verifier more consistent and intuitive by
having KF_RELEASE kfuncs imply the presence of KF_TRUSTED_ARGS. Our
eventual goal is to have all kfuncs assume KF_TRUSTED_ARGS by default
anyways, so this takes us a step in that direction.

Note that it does not make sense to assume KF_TRUSTED_ARGS for all
KF_ACQUIRE kfuncs. KF_ACQUIRE kfuncs can have looser semantics than
KF_RELEASE, with e.g. KF_RCU | KF_RET_NULL. We may want to have
KF_ACQUIRE imply KF_TRUSTED_ARGS _unless_ KF_RCU is specified, but that
can be left to another patch set, and there are no such subtleties to
address for KF_RELEASE.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230325213144.486885-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 16:56:22 -07:00
Kui-Feng Lee
06da9f3bd6 selftests/bpf: Test switching TCP Congestion Control algorithms.
Create a pair of sockets that utilize the congestion control algorithm
under a particular name. Then switch up this congestion control
algorithm to another implementation and check whether newly created
connections using the same cc name now run the new implementation.

Also, try to update a link with a struct_ops that is without
BPF_F_LINK or with a wrong or different name.  These cases should fail
due to the violation of assumptions.  To update a bpf_link of a
struct_ops, it must be replaced with another struct_ops that is
identical in type and name and has the BPF_F_LINK flag.

The other test case is to create links from the same struct_ops more
than once.  It makes sure a struct_ops can be used repeatly.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Link: https://lore.kernel.org/r/20230323032405.3735486-9-kuifeng@meta.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-22 22:53:25 -07:00
Xu Kuohai
1a3148fc17 selftests/bpf: Check when bounds are not in the 32-bit range
Add cases to check if bound is updated correctly when 64-bit value is
not in the 32-bit range.

Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230322213056.2470-2-daniel@iogearbox.net
2023-03-22 16:49:25 -07:00
Daniel Borkmann
7be14c1c90 bpf: Fix __reg_bound_offset 64->32 var_off subreg propagation
Xu reports that after commit 3f50f132d8 ("bpf: Verifier, do explicit ALU32
bounds tracking"), the following BPF program is rejected by the verifier:

   0: (61) r2 = *(u32 *)(r1 +0)          ; R2_w=pkt(off=0,r=0,imm=0)
   1: (61) r3 = *(u32 *)(r1 +4)          ; R3_w=pkt_end(off=0,imm=0)
   2: (bf) r1 = r2
   3: (07) r1 += 1
   4: (2d) if r1 > r3 goto pc+8
   5: (71) r1 = *(u8 *)(r2 +0)           ; R1_w=scalar(umax=255,var_off=(0x0; 0xff))
   6: (18) r0 = 0x7fffffffffffff10
   8: (0f) r1 += r0                      ; R1_w=scalar(umin=0x7fffffffffffff10,umax=0x800000000000000f)
   9: (18) r0 = 0x8000000000000000
  11: (07) r0 += 1
  12: (ad) if r0 < r1 goto pc-2
  13: (b7) r0 = 0
  14: (95) exit

And the verifier log says:

  func#0 @0
  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (61) r2 = *(u32 *)(r1 +0)          ; R1=ctx(off=0,imm=0) R2_w=pkt(off=0,r=0,imm=0)
  1: (61) r3 = *(u32 *)(r1 +4)          ; R1=ctx(off=0,imm=0) R3_w=pkt_end(off=0,imm=0)
  2: (bf) r1 = r2                       ; R1_w=pkt(off=0,r=0,imm=0) R2_w=pkt(off=0,r=0,imm=0)
  3: (07) r1 += 1                       ; R1_w=pkt(off=1,r=0,imm=0)
  4: (2d) if r1 > r3 goto pc+8          ; R1_w=pkt(off=1,r=1,imm=0) R3_w=pkt_end(off=0,imm=0)
  5: (71) r1 = *(u8 *)(r2 +0)           ; R1_w=scalar(umax=255,var_off=(0x0; 0xff)) R2_w=pkt(off=0,r=1,imm=0)
  6: (18) r0 = 0x7fffffffffffff10       ; R0_w=9223372036854775568
  8: (0f) r1 += r0                      ; R0_w=9223372036854775568 R1_w=scalar(umin=9223372036854775568,umax=9223372036854775823,s32_min=-240,s32_max=15)
  9: (18) r0 = 0x8000000000000000       ; R0_w=-9223372036854775808
  11: (07) r0 += 1                      ; R0_w=-9223372036854775807
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775807 R1_w=scalar(umin=9223372036854775568,umax=9223372036854775809)
  13: (b7) r0 = 0                       ; R0_w=0
  14: (95) exit

  from 12 to 11: R0_w=-9223372036854775807 R1_w=scalar(umin=9223372036854775810,umax=9223372036854775823,var_off=(0x8000000000000000; 0xffffffff)) R2_w=pkt(off=0,r=1,imm=0) R3_w=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775806
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775806 R1_w=scalar(umin=9223372036854775810,umax=9223372036854775810,var_off=(0x8000000000000000; 0xffffffff))
  13: safe

  [...]

  from 12 to 11: R0_w=-9223372036854775795 R1=scalar(umin=9223372036854775822,umax=9223372036854775823,var_off=(0x8000000000000000; 0xffffffff)) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775794
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775794 R1=scalar(umin=9223372036854775822,umax=9223372036854775822,var_off=(0x8000000000000000; 0xffffffff))
  13: safe

  from 12 to 11: R0_w=-9223372036854775794 R1=scalar(umin=9223372036854775823,umax=9223372036854775823,var_off=(0x8000000000000000; 0xffffffff)) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775793
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775793 R1=scalar(umin=9223372036854775823,umax=9223372036854775823,var_off=(0x8000000000000000; 0xffffffff))
  13: safe

  from 12 to 11: R0_w=-9223372036854775793 R1=scalar(umin=9223372036854775824,umax=9223372036854775823,var_off=(0x8000000000000000; 0xffffffff)) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775792
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775792 R1=scalar(umin=9223372036854775824,umax=9223372036854775823,var_off=(0x8000000000000000; 0xffffffff))
  13: safe

  [...]

The 64bit umin=9223372036854775810 bound continuously bumps by +1 while
umax=9223372036854775823 stays as-is until the verifier complexity limit
is reached and the program gets finally rejected. During this simulation,
the umin also eventually surpasses umax. Looking at the first 'from 12
to 11' output line from the loop, R1 has the following state:

  R1_w=scalar(umin=0x8000000000000002 (9223372036854775810),
              umax=0x800000000000000f (9223372036854775823),
          var_off=(0x8000000000000000;
                           0xffffffff))

The var_off has technically not an inconsistent state but it's very
imprecise and far off surpassing 64bit umax bounds whereas the expected
output with refined known bits in var_off should have been like:

  R1_w=scalar(umin=0x8000000000000002 (9223372036854775810),
              umax=0x800000000000000f (9223372036854775823),
          var_off=(0x8000000000000000;
                                  0xf))

In the above log, var_off stays as var_off=(0x8000000000000000; 0xffffffff)
and does not converge into a narrower mask where more bits become known,
eventually transforming R1 into a constant upon umin=9223372036854775823,
umax=9223372036854775823 case where the verifier would have terminated and
let the program pass.

The __reg_combine_64_into_32() marks the subregister unknown and propagates
64bit {s,u}min/{s,u}max bounds to their 32bit equivalents iff they are within
the 32bit universe. The question came up whether __reg_combine_64_into_32()
should special case the situation that when 64bit {s,u}min bounds have
the same value as 64bit {s,u}max bounds to then assign the latter as
well to the 32bit reg->{s,u}32_{min,max}_value. As can be seen from the
above example however, that is just /one/ special case and not a /generic/
solution given above example would still not be addressed this way and
remain at an imprecise var_off=(0x8000000000000000; 0xffffffff).

The improvement is needed in __reg_bound_offset() to refine var32_off with
the updated var64_off instead of the prior reg->var_off. The reg_bounds_sync()
code first refines information about the register's min/max bounds via
__update_reg_bounds() from the current var_off, then in __reg_deduce_bounds()
from sign bit and with the potentially learned bits from bounds it'll
update the var_off tnum in __reg_bound_offset(). For example, intersecting
with the old var_off might have improved bounds slightly, e.g. if umax
was 0x7f...f and var_off was (0; 0xf...fc), then new var_off will then
result in (0; 0x7f...fc). The intersected var64_off holds then the
universe which is a superset of var32_off. The point for the latter is
not to broaden, but to further refine known bits based on the intersection
of var_off with 32 bit bounds, so that we later construct the final var_off
from upper and lower 32 bits. The final __update_reg_bounds() can then
potentially still slightly refine bounds if more bits became known from the
new var_off.

After the improvement, we can see R1 converging successively:

  func#0 @0
  0: R1=ctx(off=0,imm=0) R10=fp0
  0: (61) r2 = *(u32 *)(r1 +0)          ; R1=ctx(off=0,imm=0) R2_w=pkt(off=0,r=0,imm=0)
  1: (61) r3 = *(u32 *)(r1 +4)          ; R1=ctx(off=0,imm=0) R3_w=pkt_end(off=0,imm=0)
  2: (bf) r1 = r2                       ; R1_w=pkt(off=0,r=0,imm=0) R2_w=pkt(off=0,r=0,imm=0)
  3: (07) r1 += 1                       ; R1_w=pkt(off=1,r=0,imm=0)
  4: (2d) if r1 > r3 goto pc+8          ; R1_w=pkt(off=1,r=1,imm=0) R3_w=pkt_end(off=0,imm=0)
  5: (71) r1 = *(u8 *)(r2 +0)           ; R1_w=scalar(umax=255,var_off=(0x0; 0xff)) R2_w=pkt(off=0,r=1,imm=0)
  6: (18) r0 = 0x7fffffffffffff10       ; R0_w=9223372036854775568
  8: (0f) r1 += r0                      ; R0_w=9223372036854775568 R1_w=scalar(umin=9223372036854775568,umax=9223372036854775823,s32_min=-240,s32_max=15)
  9: (18) r0 = 0x8000000000000000       ; R0_w=-9223372036854775808
  11: (07) r0 += 1                      ; R0_w=-9223372036854775807
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775807 R1_w=scalar(umin=9223372036854775568,umax=9223372036854775809)
  13: (b7) r0 = 0                       ; R0_w=0
  14: (95) exit

  from 12 to 11: R0_w=-9223372036854775807 R1_w=scalar(umin=9223372036854775810,umax=9223372036854775823,var_off=(0x8000000000000000; 0xf),s32_min=0,s32_max=15,u32_max=15) R2_w=pkt(off=0,r=1,imm=0) R3_w=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775806
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775806 R1_w=-9223372036854775806
  13: safe

  from 12 to 11: R0_w=-9223372036854775806 R1_w=scalar(umin=9223372036854775811,umax=9223372036854775823,var_off=(0x8000000000000000; 0xf),s32_min=0,s32_max=15,u32_max=15) R2_w=pkt(off=0,r=1,imm=0) R3_w=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775805
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775805 R1_w=-9223372036854775805
  13: safe

  [...]

  from 12 to 11: R0_w=-9223372036854775798 R1=scalar(umin=9223372036854775819,umax=9223372036854775823,var_off=(0x8000000000000008; 0x7),s32_min=8,s32_max=15,u32_min=8,u32_max=15) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775797
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775797 R1=-9223372036854775797
  13: safe

  from 12 to 11: R0_w=-9223372036854775797 R1=scalar(umin=9223372036854775820,umax=9223372036854775823,var_off=(0x800000000000000c; 0x3),s32_min=12,s32_max=15,u32_min=12,u32_max=15) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775796
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775796 R1=-9223372036854775796
  13: safe

  from 12 to 11: R0_w=-9223372036854775796 R1=scalar(umin=9223372036854775821,umax=9223372036854775823,var_off=(0x800000000000000c; 0x3),s32_min=12,s32_max=15,u32_min=12,u32_max=15) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775795
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775795 R1=-9223372036854775795
  13: safe

  from 12 to 11: R0_w=-9223372036854775795 R1=scalar(umin=9223372036854775822,umax=9223372036854775823,var_off=(0x800000000000000e; 0x1),s32_min=14,s32_max=15,u32_min=14,u32_max=15) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775794
  12: (ad) if r0 < r1 goto pc-2         ; R0_w=-9223372036854775794 R1=-9223372036854775794
  13: safe

  from 12 to 11: R0_w=-9223372036854775794 R1=-9223372036854775793 R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  11: (07) r0 += 1                      ; R0_w=-9223372036854775793
  12: (ad) if r0 < r1 goto pc-2
  last_idx 12 first_idx 12
  parent didn't have regs=1 stack=0 marks: R0_rw=P-9223372036854775801 R1_r=scalar(umin=9223372036854775815,umax=9223372036854775823,var_off=(0x8000000000000000; 0xf),s32_min=0,s32_max=15,u32_max=15) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  last_idx 11 first_idx 11
  regs=1 stack=0 before 11: (07) r0 += 1
  parent didn't have regs=1 stack=0 marks: R0_rw=P-9223372036854775805 R1_rw=scalar(umin=9223372036854775812,umax=9223372036854775823,var_off=(0x8000000000000000; 0xf),s32_min=0,s32_max=15,u32_max=15) R2_w=pkt(off=0,r=1,imm=0) R3_w=pkt_end(off=0,imm=0) R10=fp0
  last_idx 12 first_idx 0
  regs=1 stack=0 before 12: (ad) if r0 < r1 goto pc-2
  regs=1 stack=0 before 11: (07) r0 += 1
  regs=1 stack=0 before 12: (ad) if r0 < r1 goto pc-2
  regs=1 stack=0 before 11: (07) r0 += 1
  regs=1 stack=0 before 12: (ad) if r0 < r1 goto pc-2
  regs=1 stack=0 before 11: (07) r0 += 1
  regs=1 stack=0 before 9: (18) r0 = 0x8000000000000000
  last_idx 12 first_idx 12
  parent didn't have regs=2 stack=0 marks: R0_rw=P-9223372036854775801 R1_r=Pscalar(umin=9223372036854775815,umax=9223372036854775823,var_off=(0x8000000000000000; 0xf),s32_min=0,s32_max=15,u32_max=15) R2=pkt(off=0,r=1,imm=0) R3=pkt_end(off=0,imm=0) R10=fp0
  last_idx 11 first_idx 11
  regs=2 stack=0 before 11: (07) r0 += 1
  parent didn't have regs=2 stack=0 marks: R0_rw=P-9223372036854775805 R1_rw=Pscalar(umin=9223372036854775812,umax=9223372036854775823,var_off=(0x8000000000000000; 0xf),s32_min=0,s32_max=15,u32_max=15) R2_w=pkt(off=0,r=1,imm=0) R3_w=pkt_end(off=0,imm=0) R10=fp0
  last_idx 12 first_idx 0
  regs=2 stack=0 before 12: (ad) if r0 < r1 goto pc-2
  regs=2 stack=0 before 11: (07) r0 += 1
  regs=2 stack=0 before 12: (ad) if r0 < r1 goto pc-2
  regs=2 stack=0 before 11: (07) r0 += 1
  regs=2 stack=0 before 12: (ad) if r0 < r1 goto pc-2
  regs=2 stack=0 before 11: (07) r0 += 1
  regs=2 stack=0 before 9: (18) r0 = 0x8000000000000000
  regs=2 stack=0 before 8: (0f) r1 += r0
  regs=3 stack=0 before 6: (18) r0 = 0x7fffffffffffff10
  regs=2 stack=0 before 5: (71) r1 = *(u8 *)(r2 +0)
  13: safe

  from 4 to 13: safe
  verification time 322 usec
  stack depth 0
  processed 56 insns (limit 1000000) max_states_per_insn 1 total_states 3 peak_states 3 mark_read 1

This also fixes up a test case along with this improvement where we match
on the verifier log. The updated log now has a refined var_off, too.

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: Xu Kuohai <xukuohai@huaweicloud.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230314203424.4015351-2-xukuohai@huaweicloud.com
Link: https://lore.kernel.org/bpf/20230322213056.2470-1-daniel@iogearbox.net
2023-03-22 16:49:25 -07:00
JP Kobryn
830154cdc5 bpf/selftests: coverage for bpf_map_ops errors
These tests expose the issue of being unable to properly check for errors
returned from inlined bpf map helpers that make calls to the bpf_map_ops
functions. At best, a check for zero or non-zero can be done but these
tests show it is not possible to check for a negative value or for a
specific error value.

Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230322194754.185781-2-inwardvessel@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-22 15:11:06 -07:00
Alexei Starovoitov
3b2ec2140f selftests/bpf: Add light skeleton test for kfunc detection.
Add light skeleton test for kfunc detection and denylist it for s390.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230321203854.3035-5-alexei.starovoitov@gmail.com
2023-03-22 09:31:05 -07:00
Tushar Vyavahare
9a321fd330 selftests/xsk: add xdp populate metadata test
Add a new test in copy-mode for testing the copying of metadata from the
buffer in kernel-space to user-space. This is accomplished by adding a
new XDP program and using the bss map to store a counter that is written
to the metadata field. This counter is incremented for every packet so
that the number becomes unique and should be the same as the payload. It
is store in the bss so the value can be reset between runs.

The XDP program populates the metadata and the userspace program checks
the value stored in the metadata field against the payload using the new
is_metadata_correct() function. To turn this verification on or off, add
a new parameter (use_metadata) to the ifobject structure.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230320102705.306187-1-tushar.vyavahare@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-22 09:14:07 -07:00
Jakub Kicinski
c0ba861117 net: skbuff: move the fields BPF cares about directly next to the offset marker
To avoid more possible BPF dependencies with moving bitfields
around keep the fields BPF cares about right next to the offset
marker.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230321014115.997841-4-kuba@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-20 21:57:49 -07:00
Jakub Kicinski
04aae213e7 net: skbuff: rename __pkt_vlan_present_offset to __mono_tc_offset
vlan_present is gone since
commit 354259fa73 ("net: remove skb->vlan_present")
rename the offset field to what BPF is currently looking
for in this byte - mono_delivery_time and tc_at_ingress.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230321014115.997841-2-kuba@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-20 21:57:49 -07:00
Alexei Starovoitov
bb4a6a9237 selftest/bpf: Add a test case for ld_imm64 copy logic.
Add a test case to exercise {btf_id, btf_obj_fd} copy logic between ld_imm64 insns.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230319203014.55866-2-alexei.starovoitov@gmail.com
2023-03-20 09:26:41 -07:00
Manu Bretelle
2be7aa76cc selftests/bpf: Add --json-summary option to test_progs
Currently, test_progs outputs all stdout/stderr as it runs, and when it
is done, prints a summary.

It is non-trivial for tooling to parse that output and extract meaningful
information from it.

This change adds a new option, `--json-summary`/`-J` that let the caller
specify a file where `test_progs{,-no_alu32}` can write a summary of the
run in a json format that can later be parsed by tooling.

Currently, it creates a summary section with successes/skipped/failures
followed by a list of failed tests and subtests.

A test contains the following fields:
- name: the name of the test
- number: the number of the test
- message: the log message that was printed by the test.
- failed: A boolean indicating whether the test failed or not. Currently
we only output failed tests, but in the future, successful tests could
be added.
- subtests: A list of subtests associated with this test.

A subtest contains the following fields:
- name: same as above
- number: sanme as above
- message: the log message that was printed by the subtest.
- failed: same as above but for the subtest

An example run and json content below:
```
$ sudo ./test_progs -a $(grep -v '^#' ./DENYLIST.aarch64 | awk '{print
$1","}' | tr -d '\n') -j -J /tmp/test_progs.json
$ jq < /tmp/test_progs.json | head -n 30
{
  "success": 29,
  "success_subtest": 23,
  "skipped": 3,
  "failed": 28,
  "results": [
    {
      "name": "bpf_cookie",
      "number": 10,
      "message": "test_bpf_cookie:PASS:skel_open 0 nsec\n",
      "failed": true,
      "subtests": [
        {
          "name": "multi_kprobe_link_api",
          "number": 2,
          "message": "kprobe_multi_link_api_subtest:PASS:load_kallsyms 0 nsec\nlibbpf: extern 'bpf_testmod_fentry_test1' (strong): not resolved\nlibbpf: failed to load object 'kprobe_multi'\nlibbpf: failed to load BPF skeleton 'kprobe_multi': -3\nkprobe_multi_link_api_subtest:FAIL:fentry_raw_skel_load unexpected error: -3\n",
          "failed": true
        },
        {
          "name": "multi_kprobe_attach_api",
          "number": 3,
          "message": "libbpf: extern 'bpf_testmod_fentry_test1' (strong): not resolved\nlibbpf: failed to load object 'kprobe_multi'\nlibbpf: failed to load BPF skeleton 'kprobe_multi': -3\nkprobe_multi_attach_api_subtest:FAIL:fentry_raw_skel_load unexpected error: -3\n",
          "failed": true
        },
        {
          "name": "lsm",
          "number": 8,
          "message": "lsm_subtest:PASS:lsm.link_create 0 nsec\nlsm_subtest:FAIL:stack_mprotect unexpected stack_mprotect: actual 0 != expected -1\n",
          "failed": true
        }
```

The file can then be used to print a summary of the test run and list of
failing tests/subtests:

```
$ jq -r < /tmp/test_progs.json '"Success: \(.success)/\(.success_subtest), Skipped: \(.skipped), Failed: \(.failed)"'

Success: 29/23, Skipped: 3, Failed: 28
$ jq -r < /tmp/test_progs.json '.results | map([
    if .failed then "#\(.number) \(.name)" else empty end,
    (
        . as {name: $tname, number: $tnum} | .subtests | map(
            if .failed then "#\($tnum)/\(.number) \($tname)/\(.name)" else empty end
        )
    )
]) | flatten | .[]' | head -n 20
 #10 bpf_cookie
 #10/2 bpf_cookie/multi_kprobe_link_api
 #10/3 bpf_cookie/multi_kprobe_attach_api
 #10/8 bpf_cookie/lsm
 #15 bpf_mod_race
 #15/1 bpf_mod_race/ksym (used_btfs UAF)
 #15/2 bpf_mod_race/kfunc (kfunc_btf_tab UAF)
 #36 cgroup_hierarchical_stats
 #61 deny_namespace
 #61/1 deny_namespace/unpriv_userns_create_no_bpf
 #73 fexit_stress
 #83 get_func_ip_test
 #99 kfunc_dynptr_param
 #99/1 kfunc_dynptr_param/dynptr_data_null
 #99/4 kfunc_dynptr_param/dynptr_data_null
 #100 kprobe_multi_bench_attach
 #100/1 kprobe_multi_bench_attach/kernel
 #100/2 kprobe_multi_bench_attach/modules
 #101 kprobe_multi_test
 #101/1 kprobe_multi_test/skel_api
```

Signed-off-by: Manu Bretelle <chantr4@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230317163256.3809328-1-chantr4@gmail.com
2023-03-17 16:00:33 -07:00
Alexei Starovoitov
95fdf6e313 selftests/bpf: Add test for bpf_ksym_exists().
Add load and run time test for bpf_ksym_exists() and check that the verifier
performs dead code elimination for non-existing kfunc.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230317201920.62030-5-alexei.starovoitov@gmail.com
2023-03-17 15:46:02 -07:00
Alexander Lobakin
5640b6d894 selftests/bpf: fix "metadata marker" getting overwritten by the netstack
Alexei noticed xdp_do_redirect test on BPF CI started failing on
BE systems after skb PP recycling was enabled:

test_xdp_do_redirect:PASS:prog_run 0 nsec
test_xdp_do_redirect:PASS:pkt_count_xdp 0 nsec
test_xdp_do_redirect:PASS:pkt_count_zero 0 nsec
test_xdp_do_redirect:FAIL:pkt_count_tc unexpected pkt_count_tc: actual
220 != expected 9998
test_max_pkt_size:PASS:prog_run_max_size 0 nsec
test_max_pkt_size:PASS:prog_run_too_big 0 nsec
close_netns:PASS:setns 0 nsec
 #289 xdp_do_redirect:FAIL
Summary: 270/1674 PASSED, 30 SKIPPED, 1 FAILED

and it doesn't happen on LE systems.
Ilya then hunted it down to:

 #0  0x0000000000aaeee6 in neigh_hh_output (hh=0x83258df0,
skb=0x88142200) at linux/include/net/neighbour.h:503
 #1  0x0000000000ab2cda in neigh_output (skip_cache=false,
skb=0x88142200, n=<optimized out>) at linux/include/net/neighbour.h:544
 #2  ip6_finish_output2 (net=net@entry=0x88edba00, sk=sk@entry=0x0,
skb=skb@entry=0x88142200) at linux/net/ipv6/ip6_output.c:134
 #3  0x0000000000ab4cbc in __ip6_finish_output (skb=0x88142200, sk=0x0,
net=0x88edba00) at linux/net/ipv6/ip6_output.c:195
 #4  ip6_finish_output (net=0x88edba00, sk=0x0, skb=0x88142200) at
linux/net/ipv6/ip6_output.c:206

xdp_do_redirect test places a u32 marker (0x42) right before the Ethernet
header to check it then in the XDP program and return %XDP_ABORTED if it's
not there. Neigh xmit code likes to round up hard header length to speed
up copying the header, so it overwrites two bytes in front of the Eth
header. On LE systems, 0x42 is one byte at `data - 4`, while on BE it's
`data - 1`, what explains why it happens only there.
It didn't happen previously due to that %XDP_PASS meant the page will be
discarded and replaced by a new one, but now it can be recycled as well,
while bpf_test_run code doesn't reinitialize the content of recycled
pages. This mark is limited to this particular test and its setup though,
so there's no need to predict 1000 different possible cases. Just move
it 4 bytes to the left, still keeping it 32 bit to match on more bytes.

Fixes: 9c94bbf9a8 ("xdp: recycle Page Pool backed skbs built from XDP frames")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/CAADnVQ+B_JOU+EpP=DKhbY9yXdN6GiRPnpTTXfEZ9sNkUeb-yQ@mail.gmail.com
Reported-by: Ilya Leoshkevich <iii@linux.ibm.com> # + debugging
Link: https://lore.kernel.org/bpf/8341c1d9f935f410438e79d3bd8a9cc50aefe105.camel@linux.ibm.com
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230316175051.922550-3-aleksander.lobakin@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-16 22:20:09 -07:00
David Vernet
1b403ce77d bpf: Remove bpf_cpumask_kptr_get() kfunc
Now that struct bpf_cpumask is RCU safe, there's no need for this kfunc.
Rather than doing the following:

private(MASK) static struct bpf_cpumask __kptr *global;

int BPF_PROG(prog, s32 cpu, ...)
{
	struct bpf_cpumask *cpumask;

	bpf_rcu_read_lock();
	cpumask = bpf_cpumask_kptr_get(&global);
	if (!cpumask) {
		bpf_rcu_read_unlock();
		return -1;
	}
	bpf_cpumask_setall(cpumask);
	...
	bpf_cpumask_release(cpumask);
	bpf_rcu_read_unlock();
}

Programs can instead simply do (assume same global cpumask):

int BPF_PROG(prog, ...)
{
	struct bpf_cpumask *cpumask;

	bpf_rcu_read_lock();
	cpumask = global;
	if (!cpumask) {
		bpf_rcu_read_unlock();
		return -1;
	}
	bpf_cpumask_setall(cpumask);
	...
	bpf_rcu_read_unlock();
}

In other words, no extra atomic acquire / release, and less boilerplate
code.

This patch removes both the kfunc, as well as its selftests and
documentation.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230316054028.88924-5-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-16 12:28:30 -07:00
David Vernet
a5a197df58 bpf/selftests: Test using global cpumask kptr with RCU
Now that struct bpf_cpumask * is considered an RCU-safe type according
to the verifier, we should add tests that validate its common usages.
This patch adds those tests to the cpumask test suite. A subsequent
changes will remove bpf_cpumask_kptr_get(), and will adjust the selftest
and BPF documentation accordingly.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230316054028.88924-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-16 12:28:30 -07:00
Martin KaFai Lau
226efec2b0 selftests/bpf: Fix a fd leak in an error path in network_helpers.c
In __start_server, it leaks a fd when setsockopt(SO_REUSEPORT) fails.
This patch fixes it.

Fixes: eed92afdd1 ("bpf: selftest: Test batching and bpf_(get|set)sockopt in bpf tcp iter")
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230316000726.1016773-2-martin.lau@linux.dev
2023-03-16 18:12:59 +01:00
Martin KaFai Lau
ed01385c0d selftests/bpf: Use ASSERT_EQ instead ASSERT_OK for testing memcmp result
In tcp_hdr_options test, it ensures the received tcp hdr option
and the sk local storage have the expected values. It uses memcmp
to check that. Testing the memcmp result with ASSERT_OK is confusing
because ASSERT_OK will print out the errno which is not set.
This patch uses ASSERT_EQ to check for 0 instead.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230316000726.1016773-1-martin.lau@linux.dev
2023-03-16 18:12:59 +01:00
Viktor Malik
aa3d65de4b bpf/selftests: Test fentry attachment to shadowed functions
Adds a new test that tries to attach a program to fentry of two
functions of the same name, one located in vmlinux and the other in
bpf_testmod.

To avoid conflicts with existing tests, a new function
"bpf_fentry_shadow_test" was created both in vmlinux and in bpf_testmod.

The previous commit fixed a bug which caused this test to fail. The
verifier would always use the vmlinux function's address as the target
trampoline address, hence trying to create two trampolines for a single
address, which is forbidden.

The test (similarly to other fentry/fexit tests) is not working on arm64
at the moment.

Signed-off-by: Viktor Malik <vmalik@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/5fe2f364190b6f79b085066ed7c5989c5bc475fa.1678432753.git.vmalik@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-15 18:38:30 -07:00
Alexei Starovoitov
3c2611bac0 selftests/bpf: Fix trace_virtqueue_add_sgs test issue with LLVM 17.
LLVM commit https://reviews.llvm.org/D143726 introduced hoistMinMax optimization
that transformed
  (i < VIRTIO_MAX_SGS) && (i < out_sgs)
into
  i < MIN(VIRTIO_MAX_SGS, out_sgs)

and caused the verifier to stop recognizing such loop as bounded.

Which resulted in the following test failure:

libbpf: prog 'trace_virtqueue_add_sgs': BPF program load failed: Bad address
libbpf: prog 'trace_virtqueue_add_sgs': -- BEGIN PROG LOAD LOG --
The sequence of 8193 jumps is too complex.
verification time 789206 usec
stack depth 56
processed 156446 insns (limit 1000000) max_states_per_insn 7 total_states 1746 peak_states 1701 mark_read 12
-- END PROG LOAD LOG --
libbpf: prog 'trace_virtqueue_add_sgs': failed to load: -14
libbpf: failed to load object 'loop6.bpf.o'

Workaround the verifier limitation for now with inline asm that
prevents this particular optimization.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-14 15:28:11 -07:00
Alexander Lobakin
487deb3e33 selftests/bpf: robustify test_xdp_do_redirect with more payload magics
Currently, the test relies on that only dropped ("xmitted") frames will
be recycled and if a frame became an skb, it will be freed later by the
stack and never come back to its page_pool.
So, it easily gets broken by trying to recycle skbs[0]:

  test_xdp_do_redirect:PASS:pkt_count_xdp 0 nsec
  test_xdp_do_redirect:FAIL:pkt_count_zero unexpected pkt_count_zero:
actual 9936 != expected 2
  test_xdp_do_redirect:PASS:pkt_count_tc 0 nsec

That huge mismatch happened because after the TC ingress hook zeroes the
magic, the page gets recycled when skb is freed, not returned to the MM
layer. "Live frames" mode initializes only new pages and keeps the
recycled ones as is by design, so they appear with zeroed magic on the
Rx path again.
Expand the possible magic values from two: 0 (was "xmitted"/dropped or
did hit the TC hook) and 0x42 (hit the input XDP prog) to three: the new
one will mark frames hit the TC hook, so that they will elide both
@pkt_count_zero and @pkt_count_xdp. They can then be recycled to their
page_pool or returned to the page allocator, this won't affect the
counters anyhow. Just make sure to mark them as "input" (0x42) when they
appear on the Rx path again.
Also make an enum from those magics, so that they will be always visible
and can be changed in just one place anytime. This also eases adding any
new marks later on.

Link: https://github.com/kernel-patches/bpf/actions/runs/4386538411/jobs/7681081789
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20230313215553.1045175-2-aleksander.lobakin@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-14 15:20:04 -07:00
Alexei Starovoitov
f25fd60882 selftests/bpf: Add various tests to check helper access into ptr_to_btf_id.
Add various tests to check helper access into ptr_to_btf_id.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230313235845.61029-4-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-13 23:08:21 -07:00
Ross Zwisler
ab4c15feb2 selftests/bpf: use canonical ftrace path
The canonical location for the tracefs filesystem is at
/sys/kernel/tracing.

But, from Documentation/trace/ftrace.rst:

  Before 4.1, all ftrace tracing control files were within the debugfs
  file system, which is typically located at /sys/kernel/debug/tracing.
  For backward compatibility, when mounting the debugfs file system,
  the tracefs file system will be automatically mounted at:

  /sys/kernel/debug/tracing

Many tests in the bpf selftest code still refer to this older debugfs
path, so let's update them to avoid confusion.

Signed-off-by: Ross Zwisler <zwisler@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20230313205628.1058720-3-zwisler@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-13 21:51:30 -07:00