Re: [PATCH v3 bpf-next 1/2] bpf: Add range tracking for BPF_NEG

[Song Liu <songliubraving@meta.com>]

> On Jun 24, 2025, at 5:29 PM, Eduard Zingerman <eddyz87@gmail.com> wrote:
> 
> On Tue, 2025-06-24 at 16:33 -0700, Song Liu wrote:
> 
> [...]
> 
>> diff --git a/tools/testing/selftests/bpf/progs/verifier_value_ptr_arith.c b/tools/testing/selftests/bpf/progs/verifier_value_ptr_arith.c
>> index fcea9819e359..799eccd181b5 100644
>> --- a/tools/testing/selftests/bpf/progs/verifier_value_ptr_arith.c
>> +++ b/tools/testing/selftests/bpf/progs/verifier_value_ptr_arith.c
>> @@ -225,9 +225,7 @@ l2_%=: r0 = 1; \
>> 
>> SEC("socket")
>> __description("map access: known scalar += value_ptr unknown vs unknown (lt)")
>> -__success __failure_unpriv
>> -__msg_unpriv("R1 tried to add from different maps, paths or scalars")
>> -__retval(1)
>> +__success __success_unpriv __retval(1)
>> __naked void ptr_unknown_vs_unknown_lt(void)
>> {
>> asm volatile (" \
>> @@ -265,9 +263,7 @@ l2_%=: r0 = 1; \
>> 
>> SEC("socket")
>> __description("map access: known scalar += value_ptr unknown vs unknown (gt)")
>> -__success __failure_unpriv
>> -__msg_unpriv("R1 tried to add from different maps, paths or scalars")
>> -__retval(1)
>> +__success __success_unpriv __retval(1)
>> __naked void ptr_unknown_vs_unknown_gt(void)
>> {
>> asm volatile (" \
> 
> Apologies for not being clear in previous messages.
> Could you please avoid flipping these tests from __failure_unpriv to __success_unpriv?
> Instead, the tests should be rewritten to conjure an unbound scalar
> value in some different way.

I see. This is indeed the right approach. 

Thanks,
Song