Re: [PATCH v2 10/10] perf test: Fix dso data tests

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] perf test: NULL pointer dereference on dso__new() failure
- [Medium] perf: NULL pointer dereference when dso__new() fails
--

commit 2688b984099e76fca1d46c74193628a04bf63e97
Author: Namhyung Kim <namhyung@kernel.org>

perf test: Fix dso data tests

This commit fixes the dso data tests by bypassing the ELF check for binary
types so that read/write operations on the test file can proceed properly.

> diff --git a/tools/perf/tests/dso-data.c b/tools/perf/tests/dso-data.c
> index 46bc3f5972600..5a027ffab541b 100644
> --- a/tools/perf/tests/dso-data.c
> +++ b/tools/perf/tests/dso-data.c
> @@ -138,6 +138,9 @@ static int test__dso_data(struct test_suite *test __maybe_unused, int subtest __
>  	dsos__init(&machine.dsos);
>  
>  	dso = dso__new(file);
> +	/* override the binary type for dso data access */
> +	dso__set_binary_type(dso, DSO_BINARY_TYPE__SYSTEM_PATH_DSO);
> +	dso__set_bintype_searched(dso);

[Severity: Medium]
Will this crash if dso__new() fails?

If memory allocation fails and dso__new() returns NULL, these newly added
calls will unconditionally dereference the pointer, causing a segmentation
fault instead of allowing dsos__add() to handle the NULL safely and fail
the test gracefully.

>  	TEST_ASSERT_VAL("Failed to add dso", !dsos__add(&machine.dsos, dso));
>  	TEST_ASSERT_VAL("Failed to access to dso",
>  			dso__data_fd(dso, &machine) >= 0);

[ ... ]

> @@ -225,6 +228,9 @@ static int dsos__create(int cnt, int size, struct dsos *dsos)
>  
>  		TEST_ASSERT_VAL("failed to get dso file", file);
>  		dso = dso__new(file);
> +		/* override the binary type for dso data access */
> +		dso__set_binary_type(dso, DSO_BINARY_TYPE__SYSTEM_PATH_DSO);
> +		dso__set_bintype_searched(dso);

[Severity: Medium]
Similarly, does this bypass the subsequent NULL check for dso?

By unconditionally dereferencing dso, a failure from dso__new() will cause
a crash before reaching the explicit TEST_ASSERT_VAL() check intended to safely
handle this exact allocation failure.

>  		TEST_ASSERT_VAL("failed to get dso", dso);
>  		TEST_ASSERT_VAL("failed to add dso", !dsos__add(dsos, dso));
>  		dso__put(dso);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261006234315.920817-1-namhyung@kernel.org?part=10