On Wed, 27 Oct 2021 10:21:04 +0800 Jason Wang <jasowang@xxxxxxxxxx> wrote: > This patch validate the used buffer length provided by the device > before trying to use it. This is done by record the in buffer length > in a new field in desc_state structure during virtqueue_add(), then we > can fail the virtqueue_get_buf() when we find the device is trying to > give us a used buffer length which is greater than the in buffer > length. > > Since some drivers have already done the validation by themselves, > this patch tries to makes the core validation optional. For the driver > that doesn't want the validation, it can set the > suppress_used_validation to be true (which could be overridden by > force_used_validation module parameter). To be more efficient, a > dedicate array is used for storing the validate used length, this > helps to eliminate the cache stress if validation is done by the > driver. > > Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> Hi Jason! Our CI has detected, that virtio-vsock became unusable with this patch on s390x. I didn't test on x86 yet. The guest kernel says something like: vmw_vsock_virtio_transport virtio1: tx: used len 44 is larger than in buflen 0 Did you, or anybody else, see something like this on platforms other that s390x? I had a quick look at this code, and I speculate that it probably uncovers a pre-existig bug, rather than introducing a new one. If somebody is already working on this please reach out to me. Regards, Halil _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
