diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2018-04-11 10:35:40 +0800 |
|---|---|---|
| committer | Alistair Strachan <astrachan@google.com> | 2019-05-14 17:57:03 -0700 |
| commit | b8efb9dab82bcb5d99de667f0aff23fb2d341c35 (patch) | |
| tree | c80bb8066a5dd7bd2a33a1145e825039aa491a2c /drivers/vhost | |
| parent | 9a4bbdf47809d225c54647945e81bb79a26839e5 (diff) | |
UPSTREAM: vhost: fix vhost_vq_access_ok() log check
[ Upstream commit d14d2b78090c7de0557362b26a4ca591aa6a9faa ]
Commit d65026c6c62e7d9616c8ceb5a53b68bcdc050525 ("vhost: validate log
when IOTLB is enabled") introduced a regression. The logic was
originally:
if (vq->iotlb)
return 1;
return A && B;
After the patch the short-circuit logic for A was inverted:
if (A || vq->iotlb)
return A;
return B;
This patch fixes the regression by rewriting the checks in the obvious
way, no longer returning A when vq->iotlb is non-NULL (which is hard to
understand).
Reported-by: syzbot+65a84dde0214b0387ccd@syzkaller.appspotmail.com
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 72de9891b5f46f1f98e7e6243c47076a4b4daa3c)
Bug: 121166534
Test: Ran cuttlefish with android-4.4 + VSOCKETS, VMWARE_VMCI_VSOCKETS
Signed-off-by: Alistair Strachan <astrachan@google.com>
Change-Id: I63938aaa9f1cf44e4eb1a18693f8c7963eff927e
Diffstat (limited to 'drivers/vhost')
| -rw-r--r-- | drivers/vhost/vhost.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 6f4c7d2d82b4..12a01bc51cd5 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1176,10 +1176,12 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, /* Caller should have vq mutex and device mutex */ int vhost_vq_access_ok(struct vhost_virtqueue *vq) { - int ret = vq_log_access_ok(vq, vq->log_base); + if (!vq_log_access_ok(vq, vq->log_base)) + return 0; - if (ret || vq->iotlb) - return ret; + /* Access validation occurs at prefetch time with IOTLB */ + if (vq->iotlb) + return 1; return vq_access_ok(vq, vq->num, vq->desc, vq->avail, vq->used); } |