On 15.09.2015 18:07, [email protected] wrote:
> From: Marc-André Lureau <[email protected]>
>
> The number of eventfd that can be handled per peer is limited by the
> number of vectors. Return an error when receiving too many of them.
>
> Signed-off-by: Marc-André Lureau <[email protected]>
> ---
> hw/misc/ivshmem.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
> index b9c78cd..63e4c4f 100644
> --- a/hw/misc/ivshmem.c
> +++ b/hw/misc/ivshmem.c
> @@ -569,6 +569,13 @@ static void ivshmem_read(void *opaque, const uint8_t
> *buf, int size)
> }
>
> /* get a new eventfd */
> + if (peer->nb_eventfds >= s->vectors) {
> + error_report("Too many eventfd received, device has %d vectors",
> + s->vectors);
> + close(incoming_fd);
> + return;
> + }
> +
> nth_eventfd = peer->nb_eventfds++;
>
> /* this is an eventfd for a particular peer VM */
>
can the device still operate if we detect these errors at ivshmem_read time?
I am referring also to the other checks happening in ivshmem_read doing
if ([something fails]) {
error_report("abcabc");
/* close(), ... */
return;
}
Can the device stop operating if these conditions happen?
If so, do we have to put the device into a non-operating state, where all
read/writes are ignored? Should there be a ivshmem status flag for ERROR?
Should we exit(1)?
note: I don't know what the "proper" behavior should be, but I am concerned
about the runtime stability of the software which uses the device.
Ciao,
Claudio
