Re: [PATCH net] net: restrict SO_REUSEPORT to TCP, UDP and SCTP sockets

[Martin KaFai Lau <martin.lau@linux.dev>]

On 12/31/24 4:44 AM, Eric Dumazet wrote:
> On Tue, Dec 31, 2024 at 1:07 AM Jakub Kicinski <kuba@kernel.org> wrote:
>>
>> On Mon, 30 Dec 2024 19:34:30 +0000 Eric Dumazet wrote:
>>> After blamed commit, crypto sockets could accidentally be destroyed
>>> from RCU callback, as spotted by zyzbot [1].
>>>
>>> Trying to acquire a mutex in RCU callback is not allowed.
>>>
>>> Restrict SO_REUSEPORT socket option to TCP, UDP and SCTP sockets.
>>
>> Looks like fcnal_test.sh and reuseport_addr_any.sh are failing
>> after this patch, we need to adjust their respective binaries.
>> I'll hide this patch from patchwork, even tho it's probably right..
> 
> It seems we should support raw sockets, they already use SOCK_RCU_FREE anyway.
> 
> Although sk_reuseport_attach_bpf() has the following checks :
> 
> if ((sk->sk_type != SOCK_STREAM &&
>       sk->sk_type != SOCK_DGRAM) ||
>      (sk->sk_protocol != IPPROTO_UDP &&
>       sk->sk_protocol != IPPROTO_TCP) ||
>      (sk->sk_family != AF_INET &&
>       sk->sk_family != AF_INET6)) {

I think this should be mostly aligned with what is supported in the bpf 
reuseport_array and sock_map. This can be changed if other sock supported is 
added to the bpf map.

> err = -ENOTSUPP;
> goto err_prog_put;
> }