Re: [PATCH v2] selftests/seccomp: fix pointer type mismatch in UPROBE test

[Shuah Khan <skhan@linuxfoundation.org>]

On 11/25/25 04:20, Nirbhay Sharma wrote:
> 
> 
> On 10/26/25 2:42 PM, Nirbhay Sharma wrote:
>> Fix compilation error in UPROBE_setup caused by pointer type mismatch
>> in the ternary expression when compiled with -fcf-protection. The
>> probed_uprobe function pointer has the __attribute__((nocf_check))
>> attribute, which causes the conditional operator to fail when combined
>> with the regular probed_uretprobe function pointer:
>>
>>    seccomp_bpf.c:5175:74: error: pointer type mismatch in conditional
>>    expression [-Wincompatible-pointer-types]
>>
>> Cast both function pointers to 'const void *' to match the expected
>> parameter type of get_uprobe_offset(), resolving the type mismatch
>> while preserving the function selection logic.
>>
>> This error appears with compilers that enable Control Flow Integrity
>> (CFI) protection via -fcf-protection, such as Clang 19.1.2 (default
>> on Fedora).
>>
>> Signed-off-by: Nirbhay Sharma <nirbhay.lkd@gmail.com>
>> ---
>>   tools/testing/selftests/seccomp/seccomp_bpf.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
>> index 874f17763536..e13ffe18ef95 100644
>> --- a/tools/testing/selftests/seccomp/seccomp_bpf.c
>> +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
>> @@ -5172,7 +5172,8 @@ FIXTURE_SETUP(UPROBE)
>>           ASSERT_GE(bit, 0);
>>       }
>> -    offset = get_uprobe_offset(variant->uretprobe ? probed_uretprobe : probed_uprobe);
>> +    offset = get_uprobe_offset(variant->uretprobe ?
>> +        (const void *)probed_uretprobe : (const void *)probed_uprobe);
>>       ASSERT_GE(offset, 0);
>>       if (variant->uretprobe)
> 
> Hi all,
> 
> I'm following up on this patch that fixes the pointer type mismatch in
> UPROBE_setup when building with -fcf-protection. It resolves the
> incompatible-pointer-types error seen with Clang 19.
> 
> Please let me know if there are any comments or some changes needed.
> 

Hi Kees,

Is it okay to take this patch through my tree?

thanks,
-- Shuah