On Tue, Oct 8, 2024 at 6:32 PM Hou Tao <houtao@xxxxxxxxxxxxxxx> wrote:
>
> 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.
When updating include/uapi/linux/bpf.h
pls update tools/../bpf.h in the same patch as well.
pw-bot: cr
