| Message ID | 1484060780-15592-2-git-send-email-hch@lst.de (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | Mike Snitzer |
| Headers | show |
On Tue, Jan 10, 2017 at 04:06:06PM +0100, Christoph Hellwig wrote: > Most users of BLOCK_PC requests allocate the sense buffer on the stack, > so to avoid DMA to the stack copy them to a field in the heap allocated > virtblk_req structure. Without that any attempt at SCSI passthrough I/O, > including the SG_IO ioctl from userspace will crash the kernel. Note that > this includes running tools like hdparm even when the host does not have > SCSI passthrough enabled. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- Isn't that one already queued in Jens' tree? Byte, Johannes
On Wed, Jan 11, 2017 at 09:26:46AM +0100, Johannes Thumshirn wrote:
> Isn't that one already queued in Jens' tree?
Yes, it's now queued up. Patch 2 was submitted as well and should
hopefully go into the next 4.10 RC.
--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 5545a67..3c3b8f6 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -56,6 +56,7 @@ struct virtblk_req { struct virtio_blk_outhdr out_hdr; struct virtio_scsi_inhdr in_hdr; u8 status; + u8 sense[SCSI_SENSE_BUFFERSIZE]; struct scatterlist sg[]; }; @@ -102,7 +103,8 @@ static int __virtblk_add_req(struct virtqueue *vq, } if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) { - sg_init_one(&sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE); + memcpy(vbr->sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE); + sg_init_one(&sense, vbr->sense, SCSI_SENSE_BUFFERSIZE); sgs[num_out + num_in++] = &sense; sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr)); sgs[num_out + num_in++] = &inhdr;
Most users of BLOCK_PC requests allocate the sense buffer on the stack, so to avoid DMA to the stack copy them to a field in the heap allocated virtblk_req structure. Without that any attempt at SCSI passthrough I/O, including the SG_IO ioctl from userspace will crash the kernel. Note that this includes running tools like hdparm even when the host does not have SCSI passthrough enabled. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/block/virtio_blk.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)