Re: [PATCH 1/3] selftests/bpf: Route generated test headers to OUTPUT

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] Unescaped path injection in `sed` with the `@` delimiter can cause verifier tests to be silently skipped if the build path contains an `@` character.
- [Low] Generated test headers moved to $(OUTPUT) are not cleaned during out-of-tree builds because EXTRA_CLEAN is not updated.
--

--- Patch [1]: [PATCH 1/3] selftests/bpf: Route generated test headers to OUTPUT ---
commit 63d1e1deab06130ae6d45a6e98fd6e8bf85c23ef
Author: Ricardo B. Marlière (SUSE) <ricardo@marliere.net>

selftests/bpf: Route generated test headers to OUTPUT

This commit updates the Makefile to write generated test-runner enumeration
headers, verifier test lists, and signing certificate headers to $(OUTPUT)
instead of the source tree during out-of-tree builds. It modifies the
target prerequisites to ensure the output subdirectories are created before
generating these headers.

> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index b642ee489ea64..b289183475d4c 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile

[ ... ]

> @@ -923,14 +923,14 @@ $(eval $(call DEFINE_TEST_RUNNER,test_maps))
>  # It is much simpler than test_maps/test_progs and sufficiently different from
>  # them (e.g., test.h is using completely pattern), that it's worth just
>  # explicitly defining all the rules explicitly.
> -verifier/tests.h: verifier/*.c
> -	$(shell ( cd verifier/; \
> +$(OUTPUT)/verifier/tests.h: verifier/*.c | $(OUTPUT)
> +	$(shell mkdir -p $(OUTPUT)/verifier && ( \
>  		  echo '/* Generated header, do not edit */'; \
>  		  echo '#ifdef FILL_ARRAY'; \
> -		  ls *.c 2> /dev/null | sed -e 's@\(.*\)@#include \"\1\"@'; \
> +		  ls verifier/*.c 2> /dev/null | sed -e 's@\(.*\)@#include "$(CURDIR)/\1"@'; \

[Severity: Medium]
Does this change introduce a regression if the build path $(CURDIR) contains
an @ character?

If the user's working directory contains an @ symbol (such as in Jenkins
workspaces like @tmp), sed fails with a syntax error because @ is used
as the replacement delimiter.

Since the failure occurs within a subshell (...) > $(OUTPUT)/verifier/tests.h,
Make ignores the failure and writes an empty test array to the header.

Will this cause the verifier test suite to compile successfully but run zero
tests?

>  		  echo '#endif' \
> -		) > verifier/tests.h)
> -$(OUTPUT)/test_verifier: test_verifier.c verifier/tests.h $(BPFOBJ) | $(OUTPUT)
> +		) > $(OUTPUT)/verifier/tests.h)
> +$(OUTPUT)/test_verifier: test_verifier.c $(OUTPUT)/verifier/tests.h $(BPFOBJ) | $(OUTPUT)
>  	$(call msg,BINARY,,$@)
>  	$(Q)$(CC) $(CFLAGS) $(filter %.a %.o %.c,$^) $(LDLIBS) -o $@

[Severity: Low]
With the generated test headers moving to $(OUTPUT), will they be left behind
during a clean build?

Looking at EXTRA_CLEAN further down in tools/testing/selftests/bpf/Makefile:

EXTRA_CLEAN := $(SCRATCH_DIR) $(HOST_SCRATCH_DIR)			\
	prog_tests/tests.h map_tests/tests.h verifier/tests.h		\
	...

Since EXTRA_CLEAN still hardcodes the old relative paths, does this mean
`make clean O=out` will miss the newly relocated headers in the output
directory?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260728-selftests-bpf_oot-v1-0-05feb15d94db@marliere.net?part=1