From: Roman Kisel <[email protected]> Sent: Wednesday, August 27, 2025 
6:06 PM
> 
> The early failure path in __vmbus_establish_gpadl() doesn't deallocate
> msginfo if the buffer fails to decrypt.
> 
> Fix the leak by breaking out the cleanup code into a separate function
> and calling it where required.
> 
> Fixes: d4dccf353db80 ("Drivers: hv: vmbus: Mark vmbus ring buffer visible to 
> host in Isolation VM")
> Reported-by: Michael Kelley <[email protected]>
> Closes: 
> https://lore.kernel.org/linux-hyperv/sn6pr02mb41573796f9787f67e0e97049d4...@sn6pr02mb4157.namprd02.prod.outlook.com/
>  > Signed-off-by: Roman Kisel <[email protected]>

Reviewed-by: Michael Kelley <[email protected]>

> ---
>  drivers/hv/channel.c | 24 ++++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
> index 1621b95263a5..70270202209b 100644
> --- a/drivers/hv/channel.c
> +++ b/drivers/hv/channel.c
> @@ -410,6 +410,21 @@ static int create_gpadl_header(enum hv_gpadl_type type,
> void *kbuffer,
>       return 0;
>  }
> 
> +static void vmbus_free_channel_msginfo(struct vmbus_channel_msginfo *msginfo)
> +{
> +     struct vmbus_channel_msginfo *submsginfo, *tmp;
> +
> +     if (!msginfo)
> +             return;
> +
> +     list_for_each_entry_safe(submsginfo, tmp, &msginfo->submsglist,
> +                              msglistentry) {
> +             kfree(submsginfo);
> +     }
> +
> +     kfree(msginfo);
> +}
> +
>  /*
>   * __vmbus_establish_gpadl - Establish a GPADL for a buffer or ringbuffer
>   *
> @@ -429,7 +444,7 @@ static int __vmbus_establish_gpadl(struct vmbus_channel 
> *channel,
>       struct vmbus_channel_gpadl_header *gpadlmsg;
>       struct vmbus_channel_gpadl_body *gpadl_body;
>       struct vmbus_channel_msginfo *msginfo = NULL;
> -     struct vmbus_channel_msginfo *submsginfo, *tmp;
> +     struct vmbus_channel_msginfo *submsginfo;
>       struct list_head *curr;
>       u32 next_gpadl_handle;
>       unsigned long flags;
> @@ -459,6 +474,7 @@ static int __vmbus_establish_gpadl(struct vmbus_channel 
> *channel,
>                       dev_warn(&channel->device_obj->device,
>                               "Failed to set host visibility for new GPADL 
> %d.\n",
>                               ret);
> +                     vmbus_free_channel_msginfo(msginfo);
>                       return ret;
>               }
>       }
> @@ -535,12 +551,8 @@ static int __vmbus_establish_gpadl(struct vmbus_channel 
> *channel,
>       spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
>       list_del(&msginfo->msglistentry);
>       spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
> -     list_for_each_entry_safe(submsginfo, tmp, &msginfo->submsglist,
> -                              msglistentry) {
> -             kfree(submsginfo);
> -     }
> 
> -     kfree(msginfo);
> +     vmbus_free_channel_msginfo(msginfo);
> 
>       if (ret) {
>               /*
> --
> 2.43.0
> 


Reply via email to