[PATCH] nvme-tcp: check that full ICResp is received

[Sagi Grimberg]

On 23/01/2025 19:48, Caleb Sander Mateos wrote:
> nvme_tcp_init_connection() attempts to receive an ICResp PDU but only
> checks that the return value from recvmsg() is non-negative. If the
> sender closes the TCP connection or sends fewer than 128 bytes, this
> check will pass even though the full PDU wasn't received.
>
> Ensure the full ICResp PDU is received by checking that recvmsg()
> returns the expected 128 bytes.
>
> Additionally set the MSG_WAITALL flag for recvmsg(), as a sender could
> split the ICResp over multiple TCP frames. Without MSG_WAITALL,
> recvmsg() could return prematurely with only part of the PDU.

Thanks Caleb, this looks good.

I think we want to adjust the title to express that this is a bug fix, 
as well
as adding a fixes tag - so it can be picked up by stable kernels as back as
possible.

The title can perhaps be:
nvme-tcp: Fix possible connection establishment failure when receiving 
partial ICResp PDUs