Re: [PATCH v2 bpf 1/1] xskmap: reject TX-only AF_XDP sockets

[bot+bpf-ci]

> commit 6df1a89cfba973e50ce1bcafe9ffe818f3de7c06
> Author: Linpu Yu <linpu5433@xxxxxxxxx>
>
>     xskmap: reject TX-only AF_XDP sockets
>
>     XSKMAP entries are used as redirect targets for incoming XDP frames.
>     A TX-only AF_XDP socket lacks an Rx ring and cannot handle redirected
>     traffic, but xsk_map_update_elem() currently allows such sockets to
>     be inserted into the map.
>
>     Redirecting packets to such a socket on the veth generic-XDP path
>     causes a kernel crash in xsk_generic_rcv().
>
>     Reject TX-only sockets during XSKMAP updates to avoid the crash.
>     They remain fully operational for pure Tx purposes outside XSKMAP.
>
>     Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP")
                     ^^^^

Is this the correct commit to fix? The original commit fbfc504a24f5
introduced xskmap WITH a check (xsk_is_setup_for_bpf_map) that prevented
TX-only sockets from being inserted. It looks like commit 968be23ceaca
("xsk: Fix possible segfault at xskmap entry insertion") later removed
this check, which allowed TX-only sockets without Rx rings to be
inserted into the map, causing the kernel crash.

Should the Fixes tag reference 968be23ceaca instead?

>     Reported-by: Juefei Pu <tomapufckgml@xxxxxxxxx>
>     Reported-by: Yuan Tan <yuantan098@xxxxxxxxx>
>     Reported-by: Xin Liu <bird@xxxxxxxxxx>
>     Signed-off-by: Yifan Wu <yifanwucs@xxxxxxxxx>
>     Signed-off-by: Linpu Yu <linpu5433@xxxxxxxxx>

[ ... ]


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