kernel/linux.git/tools/testing/selftests/bpf/test_loader.c, branch v6.12.80

selftests/bpf: Fix caps for __xlated/jited_unpriv

2025-06-19T13:31:48+00:00

[ Upstream commit cf15cdc0f0f39a5c6315200808ec3e3995b0c2d2 ] Currently, __xlated_unpriv and __jited_unpriv do not work because the BPF syscall will overwrite info.jited_prog_len and info.xlated_prog_len with 0 if the process is not bpf_capable(). This bug was not noticed before, because there is no test that actually uses __xlated_unpriv/__jited_unpriv. To resolve this, simply restore the capabilities earlier (but still after loading the program). Adding this here unconditionally is fine because the function first checks that the capabilities were initialized before attempting to restore them. This will be important later when we add tests that check whether a speculation barrier was inserted in the correct location. Signed-off-by: Luis Gerhorst Fixes: 9c9f73391310 ("selftests/bpf: allow checking xlated programs in verifier_* tests") Fixes: 7d743e4c759c ("selftests/bpf: __jited test tag to check disassembly after jit") Acked-by: Kumar Kartikeya Dwivedi Tested-by: Eduard Zingerman Link: https://lore.kernel.org/r/20250501073603.1402960-2-luis.gerhorst@fau.de Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

selftests/bpf: attach struct_ops maps before test prog runs

2024-08-30T01:15:45+00:00

In test_loader based tests to bpf_map__attach_struct_ops() before call to bpf_prog_test_run_opts() in order to trigger bpf_struct_ops->reg() callbacks on kernel side. This allows to use __retval macro for struct_ops tests. Signed-off-by: Eduard Zingerman Signed-off-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20240829210833.388152-6-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov

selftests/bpf: test_loader.c:get_current_arch() should not return 0

2024-08-23T14:29:02+00:00

At the moment, when test_loader.c:get_current_arch() can't determine the arch, it returns 0. The arch check in run_subtest() looks as follows: if ((get_current_arch() & spec->arch_mask) == 0) { test__skip(); return; } Which means that all test_loader based tests would be skipped if arch could not be determined. get_current_arch() recognizes x86_64, arm64 and riscv64. Which means that CI skips test_loader tests for s390. Fix this by making sure that get_current_arch() always returns non-zero value. In combination with default spec->arch_mask == -1 this should cover all possibilities. Fixes: f406026fefa7 ("selftests/bpf: by default use arch mask allowing all archs") Fixes: 7d743e4c759c ("selftests/bpf: __jited test tag to check disassembly after jit") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240823080644.263943-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: by default use arch mask allowing all archs

2024-08-22T15:35:21+00:00

If test case does not specify architecture via __arch_* macro consider that it should be run for all architectures. Fixes: 7d743e4c759c ("selftests/bpf: __jited test tag to check disassembly after jit") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240822084112.3257995-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: validate xlated same way as jited

2024-08-21T18:03:01+00:00

Both __xlated and __jited work with disassembly. It is logical to have both work in a similar manner. This commit updates __xlated macro handling in test_loader.c by making it expect matches on sequential lines, same way as __jited operates. For example: __xlated("1: *(u64 *)(r10 -16) = r1") ;; matched on line N __xlated("3: r0 = &(void __percpu *)(r0)") ;; matched on line N+1 Also: __xlated("1: *(u64 *)(r10 -16) = r1") ;; matched on line N __xlated("...") ;; not matched __xlated("3: r0 = &(void __percpu *)(r0)") ;; mantched on any ;; line >= N Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240820102357.3372779-10-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: __jited test tag to check disassembly after jit

2024-08-21T18:03:01+00:00

Allow to verify jit behaviour by writing tests as below: SEC("tp") __arch_x86_64 __jited(" endbr64") __jited(" nopl (%rax,%rax)") __jited(" xorq %rax, %rax") ... __naked void some_test(void) { asm volatile (... ::: __clobber_all); } Allow regular expressions in patterns, same way as in __msg. By default assume that each __jited pattern has to be matched on the next consecutive line of the disassembly, e.g.: __jited(" endbr64") # matched on line N __jited(" nopl (%rax,%rax)") # matched on line N+1 If match occurs on a wrong line an error is reported. To override this behaviour use __jited("..."), e.g.: __jited(" endbr64") # matched on line N __jited("...") # not matched __jited(" nopl (%rax,%rax)") # matched on any line >= N Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240820102357.3372779-7-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

selftests/bpf: replace __regex macro with "{{...}}" patterns

2024-08-21T18:03:00+00:00

Upcoming changes require a notation to specify regular expression matches for regular verifier log messages, disassembly of BPF instructions, disassembly of jited instructions. Neither basic nor extended POSIX regular expressions w/o additional escaping are good for this role because of wide use of special characters in disassembly, for example: movq -0x10(%rbp), %rax ;; () are special characters cmpq $0x21, %rax ;; $ is a special character *(u64 *)(r10 -16) = r1 ;; * and () are special characters This commit borrows syntax from LLVM's FileCheck utility. It replaces __regex macro with ability to embed regular expressions in __msg patters using "{{" "}}" pairs for escaping. Syntax for __msg patterns: pattern := ( | regex)* regex := "{{" "}}" For example, pattern "foo{{[0-9]+}}" matches strings like "foo0", "foo007", etc. Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240820102357.3372779-5-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

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

2024-08-21T18:03:00+00:00

__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

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

2024-08-21T18:03:00+00:00

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

selftests/bpf: less spam in the log for message matching

2024-08-21T18:03:00+00:00

When running test_loader based tests in the verbose mode each matched message leaves a trace in the stderr, e.g.: ./test_progs -vvv -t ... validate_msgs:PASS:expect_msg 0 nsec validate_msgs:PASS:expect_msg 0 nsec validate_msgs:PASS:expect_msg 0 nsec validate_msgs:PASS:expect_msg 0 nsec validate_msgs:PASS:expect_msg 0 nsec This is not very helpful when debugging such tests and clobbers the log a lot. Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240820102357.3372779-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

kernel/linux.git/tools/testing/selftests/bpf/test_loader.c, branch v6.12.80

selftests/bpf: Fix caps for __xlated/jited_unpriv

selftests/bpf: attach struct_ops maps before test prog runs

selftests/bpf: test_loader.c:get_current_arch() should not return 0

selftests/bpf: by default use arch mask allowing all archs

selftests/bpf: validate __xlated same way as __jited

selftests/bpf: __jited test tag to check disassembly after jit

selftests/bpf: replace __regex macro with "{{...}}" patterns

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

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

selftests/bpf: less spam in the log for message matching

selftests/bpf: validate xlated same way as jited