Re: [PATCH v2] tools/libbpf: signedness bug in btf_dedup_ref_type()

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

Em Thu, Feb 28, 2019 at 08:50:35PM +0300, Dan Carpenter escreveu:
> The "ref_type_id" variable needs to be signed for the error handling
> to work.

Does the infiniband signedness change comes as a bonus? :-)

- Arnaldo
 
> Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> Acked-by: Andrii Nakryiko <andriin@fb.com>
> ---
> v2: Use reverse Christmas tree style
> 
> This goes through the BPF tree probably, although it does apply to
> net-next.
> 
>  drivers/infiniband/ulp/iser/iscsi_iser.h | 2 +-
>  tools/lib/bpf/btf.c                      | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
> index 120b40829560..ee7d3f6a666e 100644
> --- a/drivers/infiniband/ulp/iser/iscsi_iser.h
> +++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
> @@ -197,7 +197,7 @@ struct iser_data_buf {
>  	struct scatterlist *sg;
>  	int                size;
>  	unsigned long      data_len;
> -	unsigned int       dma_nents;
> +	int		   dma_nents;
>  };
>  
>  /* fwd declarations */
> diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> index 68b50e9bbde1..00a2f06e38fd 100644
> --- a/tools/lib/bpf/btf.c
> +++ b/tools/lib/bpf/btf.c
> @@ -2326,7 +2326,8 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
>  	struct btf_type *t, *cand;
>  	/* if we don't find equivalent type, then we are representative type */
>  	__u32 new_id = type_id;
> -	__u32 h, ref_type_id;
> +	int ref_type_id;
> +	__u32 h;
>  
>  	if (d->map[type_id] == BTF_IN_PROGRESS_ID)
>  		return -ELOOP;
> -- 
> 2.17.1

-- 

- Arnaldo