Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael Tsirkin:
 "Several small bugfixes all over the place.

  Most notably, fixes the vsock allocation with GFP_KERNEL in atomic
  context, which has been triggering warnings for lots of testers"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost/scsi: null-ptr-dereference in vhost_scsi_get_req()
  vsock/virtio: use GFP_ATOMIC under RCU read lock
  virtio_console: fix misc probe bugs
  virtio_ring: tag event_triggered as racy for KCSAN
  vdpa/octeon_ep: Fix format specifier for pointers in debug messages

1 files changed, 15 insertions, 12 deletions

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 7db9bbdfb038..718fa4e0b31e 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -1029,20 +1029,23 @@ vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 		/* virtio-scsi spec requires byte 0 of the lun to be 1 */
 		vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 	} else {
-		struct vhost_scsi_tpg **vs_tpg, *tpg;
-
-		vs_tpg = vhost_vq_get_backend(vq);	/* validated at handler entry */
-
-		tpg = READ_ONCE(vs_tpg[*vc->target]);
-		if (unlikely(!tpg)) {
-			vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
-		} else {
-			if (tpgp)
-				*tpgp = tpg;
-			ret = 0;
+		struct vhost_scsi_tpg **vs_tpg, *tpg = NULL;
+
+		if (vc->target) {
+			/* validated at handler entry */
+			vs_tpg = vhost_vq_get_backend(vq);
+			tpg = READ_ONCE(vs_tpg[*vc->target]);
+			if (unlikely(!tpg)) {
+				vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
+				goto out;
+			}
 		}
-	}
 
+		if (tpgp)
+			*tpgp = tpg;
+		ret = 0;
+	}
+out:
 	return ret;
 }