Hi,
On 10/9/2024 2:33 AM, Andrii Nakryiko wrote:
> On Tue, Oct 8, 2024 at 2:05 AM Hou Tao <houtao@xxxxxxxxxxxxxxx> wrote:
>> From: Hou Tao <houtao1@xxxxxxxxxx>
>>
>> There is an out-of-bounds read in bpf_link_show_fdinfo() for the sockmap
>> link fd. Fix it by adding the missing BPF_LINK_TYPE invocation for
>> sockmap link
>>
>> Also add comments for bpf_link_type to prevent missing updates in the
>> future.
>>
>> Fixes: 699c23f02c65 ("bpf: Add bpf_link support for sk_msg and sk_skb progs")
>> Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
>> ---
>> include/linux/bpf_types.h | 1 +
>> include/uapi/linux/bpf.h | 3 +++
>> 2 files changed, 4 insertions(+)
>>
>> diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
>> index 9f2a6b83b49e..fa78f49d4a9a 100644
>> --- a/include/linux/bpf_types.h
>> +++ b/include/linux/bpf_types.h
>> @@ -146,6 +146,7 @@ BPF_LINK_TYPE(BPF_LINK_TYPE_XDP, xdp)
>> BPF_LINK_TYPE(BPF_LINK_TYPE_NETFILTER, netfilter)
>> BPF_LINK_TYPE(BPF_LINK_TYPE_TCX, tcx)
>> BPF_LINK_TYPE(BPF_LINK_TYPE_NETKIT, netkit)
>> +BPF_LINK_TYPE(BPF_LINK_TYPE_SOCKMAP, sockmap)
>> #endif
>> #ifdef CONFIG_PERF_EVENTS
>> BPF_LINK_TYPE(BPF_LINK_TYPE_PERF_EVENT, perf)
>> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
>> index e8241b320c6d..4a939c90dc2e 100644
>> --- a/include/uapi/linux/bpf.h
>> +++ b/include/uapi/linux/bpf.h
>> @@ -1121,6 +1121,9 @@ enum bpf_attach_type {
>>
>> #define MAX_BPF_ATTACH_TYPE __MAX_BPF_ATTACH_TYPE
>>
>> +/* Add BPF_LINK_TYPE(type, name) in bpf_types.h to keep bpf_link_type_strs[]
>> + * in sync with the definitions below.
>> + */
>
> Let's also add some static assert making sure that bpf_link_type_strs
> (and probably same for other types) size is equal to
> __MAX_BPF_LINK_TYPE? Comment is good to remind us, but compilation
> error is better.
Good idea. Will check for other candidates for static assert. Will do in v2.
>
>> enum bpf_link_type {
>> BPF_LINK_TYPE_UNSPEC = 0,
>> BPF_LINK_TYPE_RAW_TRACEPOINT = 1,
>> --
>> 2.29.2
>>
