linux-stable.git/tools/testing/selftests/bpf, branch linux-6.10.y

selftests/bpf: correctly move 'log' upon successful match

2024-10-04T14:33:24+00:00

commit d0a29cdb6ef95d8a175e09ab2d1334271f047e60 upstream.

Suppose log="foo bar buz" and msg->substr="bar".
In such case current match processing logic would update 'log' as
follows: log += strlen(msg->substr); -> log += 3 -> log=" bar".
However, the intent behind the 'log' update is to make it point after
the successful match, e.g. to make log=" buz" in the example above.

Fixes: 4ef5d6af4935 ("selftests/bpf: no need to track next_match_pos in struct test_loader")
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240820102357.3372779-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Greg Kroah-Hartman

selftests/bpf: Fix incorrect parameters in NULL pointer checking

2024-10-04T14:32:56+00:00

[ Upstream commit c264487e5410e5a72db8a414566ab7d144223e6c ]

Smatch reported the following warning:
    ./tools/testing/selftests/bpf/testing_helpers.c:455 get_xlated_program()
    warn: variable dereferenced before check 'buf' (see line 454)

It seems correct,so let's modify it based on it's suggestion.

Actually,commit b23ed4d74c4d ("selftests/bpf: Fix invalid pointer
check in get_xlated_program()") fixed an issue in the test_verifier.c
once,but it was reverted this time.

Let's solve this issue with the minimal changes possible.

Reported-by: Dan Carpenter 
Closes: https://lore.kernel.org/all/1eb3732f-605a-479d-ba64-cd14250cbf91@stanley.mountain/
Fixes: b4b7a4099b8c ("selftests/bpf: Factor out get_xlated_program() helper")
Signed-off-by: Hao Ge 
Link: https://lore.kernel.org/r/20240820023622.29190-1-hao.ge@linux.dev
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: fix to avoid __msg tag de-duplication by clang

2024-10-04T14:32:55+00:00

[ Upstream commit f00bb757ed630affc951691ddaff206039cbb7ee ]

__msg, __regex and __xlated tags are based on
__attribute__((btf_decl_tag("..."))) annotations.

Clang de-duplicates such annotations, e.g. the following
two sequences of tags are identical in final BTF:

    /* seq A */            /* seq B */
    __tag("foo")           __tag("foo")
    __tag("bar")           __tag("bar")
    __tag("foo")

Fix this by adding a unique suffix for each tag using __COUNTER__
pre-processor macro. E.g. here is a new definition for __msg:

    #define __msg(msg) \
      __attribute__((btf_decl_tag("comment:test_expect_msg=" XSTR(__COUNTER__) "=" msg)))

Using this definition the "seq A" from example above is translated to
BTF as follows:

    [..] DECL_TAG 'comment:test_expect_msg=0=foo' type_id=X component_idx=-1
    [..] DECL_TAG 'comment:test_expect_msg=1=bar' type_id=X component_idx=-1
    [..] DECL_TAG 'comment:test_expect_msg=2=foo' type_id=X component_idx=-1

Surprisingly, this bug affects a single existing test:
verifier_spill_fill/old_stack_misc_vs_cur_ctx_ptr,
where sequence of identical messages was expected in the log.

Fixes: 537c3f66eac1 ("selftests/bpf: add generic BPF program tester-loader")
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240820102357.3372779-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: __arch_* macro to limit test cases to specific archs

2024-10-04T14:32:55+00:00

[ Upstream commit ee7fe84468b1732fe65c5af3836437d54ac4c419 ]

Add annotations __arch_x86_64, __arch_arm64, __arch_riscv64
to specify on which architecture the test case should be tested.
Several __arch_* annotations could be specified at once.
When test case is not run on current arch it is marked as skipped.

For example, the following would be tested only on arm64 and riscv64:

  SEC("raw_tp")
  __arch_arm64
  __arch_riscv64
  __xlated("1: *(u64 *)(r10 - 16) = r1")
  __xlated("2: call")
  __xlated("3: r1 = *(u64 *)(r10 - 16);")
  __success
  __naked void canary_arm64_riscv64(void)
  {
  	asm volatile (
  	"r1 = 1;"
  	"*(u64 *)(r10 - 16) = r1;"
  	"call %[bpf_get_smp_processor_id];"
  	"r1 = *(u64 *)(r10 - 16);"
  	"exit;"
  	:
  	: __imm(bpf_get_smp_processor_id)
  	: __clobber_all);
  }

On x86 it would be skipped:

  #467/2   verifier_nocsr/canary_arm64_riscv64:SKIP

Acked-by: Andrii Nakryiko 
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240722233844.1406874-10-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Andrii Nakryiko 
Stable-dep-of: f00bb757ed63 ("selftests/bpf: fix to avoid __msg tag de-duplication by clang")
Signed-off-by: Sasha Levin

selftests/bpf: allow checking xlated programs in verifier_* tests

2024-10-04T14:32:55+00:00

[ Upstream commit 9c9f7339131030949a8ef111080427ff1a8085b5 ]

Add a macro __xlated("...") for use with test_loader tests.

When such annotations are present for the test case:
- bpf_prog_get_info_by_fd() is used to get BPF program after all
  rewrites are applied by verifier.
- the program is disassembled and patterns specified in __xlated are
  searched for in the disassembly text.

__xlated matching follows the same mechanics as __msg:
each subsequent pattern is matched from the point where
previous pattern ended.

This allows to write tests like below, where the goal is to verify the
behavior of one of the of the transformations applied by verifier:

    SEC("raw_tp")
    __xlated("1: w0 = ")
    __xlated("2: r0 = &(void __percpu *)(r0)")
    __xlated("3: r0 = *(u32 *)(r0 +0)")
    __xlated("4: exit")
    __success __naked void simple(void)
    {
            asm volatile (
            "call %[bpf_get_smp_processor_id];"
            "exit;"
            :
            : __imm(bpf_get_smp_processor_id)
            : __clobber_all);
    }

Acked-by: Andrii Nakryiko 
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240722233844.1406874-9-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Andrii Nakryiko 
Stable-dep-of: f00bb757ed63 ("selftests/bpf: fix to avoid __msg tag de-duplication by clang")
Signed-off-by: Sasha Levin

selftests/bpf: extract test_loader->expect_msgs as a data structure

2024-10-04T14:32:55+00:00

[ Upstream commit 64f01e935ddb26f48baec71883c27878ac4231dc ]

Non-functional change: use a separate data structure to represented
expected messages in test_loader.
This would allow to use the same functionality for expected set of
disassembled instructions in the follow-up commit.

Acked-by: Andrii Nakryiko 
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240722233844.1406874-8-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Andrii Nakryiko 
Stable-dep-of: f00bb757ed63 ("selftests/bpf: fix to avoid __msg tag de-duplication by clang")
Signed-off-by: Sasha Levin

selftests/bpf: no need to track next_match_pos in struct test_loader

2024-10-04T14:32:55+00:00

[ Upstream commit 4ef5d6af493558124b7a6c13cace58b938fe27d4 ]

The call stack for validate_case() function looks as follows:
- test_loader__run_subtests()
  - process_subtest()
    - run_subtest()
      - prepare_case(), which does 'tester->next_match_pos = 0';
      - validate_case(), which increments tester->next_match_pos.

Hence, each subtest is run with next_match_pos freshly set to zero.
Meaning that there is no need to persist this variable in the
struct test_loader, use local variable instead.

Acked-by: Andrii Nakryiko 
Signed-off-by: Eduard Zingerman 
Link: https://lore.kernel.org/r/20240722233844.1406874-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Andrii Nakryiko 
Stable-dep-of: f00bb757ed63 ("selftests/bpf: fix to avoid __msg tag de-duplication by clang")
Signed-off-by: Sasha Levin

selftests/bpf: Support checks against a regular expression

2024-10-04T14:32:54+00:00

[ Upstream commit f06ae6194f278444201e0b041a00192d794f83b6 ]

Add support for __regex and __regex_unpriv macros to check the test
execution output against a regular expression. This is similar to __msg
and __msg_unpriv, however those expect do substring matching.

Signed-off-by: Cupertino Miranda 
Signed-off-by: Andrii Nakryiko 
Acked-by: Eduard Zingerman 
Link: https://lore.kernel.org/bpf/20240617141458.471620-2-cupertino.miranda@oracle.com
Stable-dep-of: f00bb757ed63 ("selftests/bpf: fix to avoid __msg tag de-duplication by clang")
Signed-off-by: Sasha Levin

selftests/bpf: Fix error compiling tc_redirect.c with musl libc

2024-10-04T14:32:54+00:00

[ Upstream commit 21c5f4f55da759c7444a1ef13e90b6e6f674eeeb ]

Linux 5.1 implemented 64-bit time types and related syscalls to address the
Y2038 problem generally across archs. Userspace handling of Y2038 varies
with the libc however. While musl libc uses 64-bit time across all 32-bit
and 64-bit platforms, GNU glibc uses 64-bit time on 64-bit platforms but
defaults to 32-bit time on 32-bit platforms unless they "opt-in" to 64-bit
time or explicitly use 64-bit syscalls and time structures.

One specific area is the standard setsockopt() call, SO_TIMESTAMPNS option
used for timestamping, and the related output 'struct timespec'. GNU glibc
defaults as above, also exposing the SO_TIMESTAMPNS_NEW flag to explicitly
use a 64-bit call and 'struct __kernel_timespec'. Since these are not
exposed or needed with musl libc, their use in tc_redirect.c leads to
compile errors building for mips64el/musl:

  tc_redirect.c: In function 'rcv_tstamp':
  tc_redirect.c:425:32: error: 'SO_TIMESTAMPNS_NEW' undeclared (first use in this function); did you mean 'SO_TIMESTAMPNS'?
    425 |             cmsg->cmsg_type == SO_TIMESTAMPNS_NEW)
        |                                ^~~~~~~~~~~~~~~~~~
        |                                SO_TIMESTAMPNS
  tc_redirect.c:425:32: note: each undeclared identifier is reported only once for each function it appears in
  tc_redirect.c: In function 'test_inet_dtime':
  tc_redirect.c:491:49: error: 'SO_TIMESTAMPNS_NEW' undeclared (first use in this function); did you mean 'SO_TIMESTAMPNS'?
    491 |         err = setsockopt(listen_fd, SOL_SOCKET, SO_TIMESTAMPNS_NEW,
        |                                                 ^~~~~~~~~~~~~~~~~~
        |                                                 SO_TIMESTAMPNS

However, using SO_TIMESTAMPNS_NEW isn't strictly needed, nor is Y2038 being
explicitly tested. The timestamp checks in tc_redirect.c are simple: the
packet receive timestamp is non-zero and processed/handled in less than 5
seconds.

Switch to using the standard setsockopt() call and SO_TIMESTAMPNS option to
ensure compatibility across glibc and musl libc. In the worst-case, there
is a 5-second window 14 years from now where tc_redirect tests may fail on
32-bit systems. However, we should reasonably expect glibc to adopt a
64-bit mandate rather than the current "opt-in" policy before the Y2038
roll-over.

Fixes: ce6f6cffaeaa ("selftests/bpf: Wait for the netstamp_needed_key static key to be turned on")
Fixes: c803475fd8dd ("bpf: selftests: test skb->tstamp in redirect_neigh")
Signed-off-by: Tony Ambardar 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/031d656c058b4e55ceae56ef49c4e1729b5090f3.1722244708.git.tony.ambardar@gmail.com
Signed-off-by: Sasha Levin

selftests/bpf: Fix compile if backtrace support missing in libc

2024-10-04T14:32:54+00:00

[ Upstream commit c9a83e76b5a96801a2c7ea0a79ca77c356d8b38d ]

Include GNU  header only with glibc and provide weak, stubbed
backtrace functions as a fallback in test_progs.c. This allows for non-GNU
replacements while avoiding compile errors (e.g. with musl libc) like:

  test_progs.c:13:10: fatal error: execinfo.h: No such file or directory
     13 | #include  /* backtrace */
        |          ^~~~~~~~~~~~
  test_progs.c: In function 'crash_handler':
  test_progs.c:1034:14: error: implicit declaration of function 'backtrace' [-Werror=implicit-function-declaration]
   1034 |         sz = backtrace(bt, ARRAY_SIZE(bt));
        |              ^~~~~~~~~
  test_progs.c:1045:9: error: implicit declaration of function 'backtrace_symbols_fd' [-Werror=implicit-function-declaration]
   1045 |         backtrace_symbols_fd(bt, sz, STDERR_FILENO);
        |         ^~~~~~~~~~~~~~~~~~~~

Fixes: 9fb156bb82a3 ("selftests/bpf: Print backtrace on SIGSEGV in test_progs")
Signed-off-by: Tony Ambardar 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/aa6dc8e23710cb457b278039d0081de7e7b4847d.1722244708.git.tony.ambardar@gmail.com
Signed-off-by: Sasha Levin