RE: [EXTERNAL] [PATCH] hv: utils: handle and propagate errors in kvp_register

Long Li
2026-04-14T17:48:07Z

> Make kvp_register() return an error code instead of silently ignoring failures, and
> propagate the error from kvp_handle_handshake() instead of returning success.
>
> This propagates both kzalloc_obj() and hvutil_transport_send() failures to
> kvp_handle_handshake() and thus to kvp_on_msg().
>
> Fixes: 245ba56a52a3 ("Staging: hv: Implement key/value pair (KVP)")
> Cc: stable@vger.kernel.org
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

Reviewed-by: Long Li <longli@microsoft.com>

> ---
> drivers/hv/hv_kvp.c | 25 +++++++++++++------------
> 1 file changed, 13 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c index
> 0d73daf745a7..6180ebe040ff 100644
> --- a/drivers/hv/hv_kvp.c
> +++ b/drivers/hv/hv_kvp.c
> @@ -93,7 +93,7 @@ static void kvp_send_key(struct work_struct *dummy);
> static void kvp_respond_to_host(struct hv_kvp_msg *msg, int error); static void
> kvp_timeout_func(struct work_struct *dummy); static void
> kvp_host_handshake_func(struct work_struct *dummy); -static void
> kvp_register(int);
> +static int kvp_register(int);
>
> static DECLARE_DELAYED_WORK(kvp_timeout_work, kvp_timeout_func); static
> DECLARE_DELAYED_WORK(kvp_host_handshake_work,
> kvp_host_handshake_func); @@ -127,24 +127,26 @@ static void
> kvp_register_done(void)
> hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper); }
>
> -static void
> +static int
> kvp_register(int reg_value)
> {
>
> struct hv_kvp_msg *kvp_msg;
> char *version;
> + int ret;
>
> kvp_msg = kzalloc_obj(*kvp_msg);
> + if (!kvp_msg)
> + return -ENOMEM;
>
> - if (kvp_msg) {
> - version = kvp_msg->body.kvp_register.version;
> - kvp_msg->kvp_hdr.operation = reg_value;
> - strcpy(version, HV_DRV_VERSION);
> + version = kvp_msg->body.kvp_register.version;
> + kvp_msg->kvp_hdr.operation = reg_value;
> + strcpy(version, HV_DRV_VERSION);
>
> - hvutil_transport_send(hvt, kvp_msg, sizeof(*kvp_msg),
> - kvp_register_done);
> - kfree(kvp_msg);
> - }
> + ret = hvutil_transport_send(hvt, kvp_msg, sizeof(*kvp_msg),
> + kvp_register_done);
> + kfree(kvp_msg);
> + return ret;
> }
>
> static void kvp_timeout_func(struct work_struct *dummy) @@ -186,9 +188,8
> @@ static int kvp_handle_handshake(struct hv_kvp_msg *msg)
> */
> pr_debug("KVP: userspace daemon ver. %d connected\n",
> msg->kvp_hdr.operation);
> - kvp_register(dm_reg_value);
>
> - return 0;
> + return kvp_register(dm_reg_value);
> }
>
>