Re: [PATCH bpf-next v3 7/9] bpf, arm64: Fix private stack leak when JIT failed

On 2026/7/25 23:55, [email protected] wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> 
> Pre-existing issues:
> - [Medium] Memory leak of the BPF private stack in the PowerPC JIT compiler upon JIT failure.
> --
> 
> --- Patch [7]: [PATCH bpf-next v3 7/9] bpf, arm64: Fix private stack leak when JIT failed ---
> commit 8de8b0f7fc232dba7540d3099301a4c55f3544c0
> Author: Pu Lehui <[email protected]>
> 
> bpf, arm64: Fix private stack leak when JIT failed
> 
> This patch fixes a memory leak in the ARM64 BPF JIT compiler. When JIT
> compilation fails, the private stack percpu memory was being leaked because
> the cleanup check evaluated to false after a pointer was left dangling. The
> fix sets the pointer to NULL to ensure proper cleanup.
> 
>> diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
>> index f4e4d4578e38a..6e036acf80d8b 100644
>> --- a/arch/arm64/net/bpf_jit_comp.c
>> +++ b/arch/arm64/net/bpf_jit_comp.c
>> @@ -2311,6 +2311,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_pr
>>   		bpf_arch_text_copy(&ro_header->size, &header->size,
>>   				   sizeof(header->size));
>>   		bpf_jit_binary_pack_free(ro_header, header);
>> +		ro_header = NULL;
> 
> [Severity: Medium]
> This is a pre-existing issue, but while fixing this memory leak for arm64,
> it appears that the PowerPC JIT compiler has the exact same problem.
> 
> In arch/powerpc/net/bpf_jit_comp.c:bpf_int_jit_compile():
> 
> 		if (bpf_jit_build_body(fp, code_base, fcode_base, &cgctx, addrs, pass,
> 				       extra_pass)) {
> 			bpf_arch_text_copy(&fhdr->size, &hdr->size, sizeof(hdr->size));
> 			bpf_jit_binary_pack_free(fhdr, hdr);
> 			goto out_err;
> 		}
> 
> When jumping to the error cleanup path, the JIT binary is freed but the image
> pointer remains non-NULL.
> 
> Then in the cleanup path:
> 
> out_addrs:
> 		if (!image && priv_stack_ptr) {
> 			fp->aux->priv_stack_ptr = NULL;
> 			free_percpu(priv_stack_ptr);
> 		}
> 
> Because the image pointer is still non-NULL, this check evaluates to false.
> Can this also cause the private stack percpu memory to be leaked in the
> PowerPC JIT? Should a similar fix be applied there?
> 
>>   	}
>>   	goto out_off;
>>   }
> 

will fix if have new version, or will send new patch