[PATCH bpf-nex] bpf: Fix an inconsitency between copies of bpf.h.

[PATCH bpf-nex] bpf: Fix an inconsitency between copies of bpf.h.

[Kui-Feng Lee]

struct bpf_lpm_trie_key is inconsistent in two copies of bpf.h.
It cuases a warning message during building the kernel.

Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
---
 include/uapi/linux/bpf.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 934a2a8beb87..1d6085e15fc8 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -79,7 +79,7 @@ struct bpf_insn {
 /* Key of an a BPF_MAP_TYPE_LPM_TRIE entry */
 struct bpf_lpm_trie_key {
 	__u32	prefixlen;	/* up to 32 for AF_INET, 128 for AF_INET6 */
-	__u8	data[];	/* Arbitrary size */
+	__u8	data[0];	/* Arbitrary size */
 };
 
 struct bpf_cgroup_storage_key {
-- 
2.30.2

Re: [PATCH bpf-nex] bpf: Fix an inconsitency between copies of bpf.h.

[Daniel Borkmann]

On 8/22/22 9:52 PM, Kui-Feng Lee wrote:
> struct bpf_lpm_trie_key is inconsistent in two copies of bpf.h.
> It cuases a warning message during building the kernel.
> 
> Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
> ---
>   include/uapi/linux/bpf.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index 934a2a8beb87..1d6085e15fc8 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -79,7 +79,7 @@ struct bpf_insn {
>   /* Key of an a BPF_MAP_TYPE_LPM_TRIE entry */
>   struct bpf_lpm_trie_key {
>   	__u32	prefixlen;	/* up to 32 for AF_INET, 128 for AF_INET6 */
> -	__u8	data[];	/* Arbitrary size */
> +	__u8	data[0];	/* Arbitrary size */
>   };
>   
>   struct bpf_cgroup_storage_key {
> 

This is fixed in bpf tree already, so it will propagate to bpf-next soon.

https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=3024d95a4c521c278a7504ee9e80c57c3a9750e0

Thanks,
Daniel