From: Eric Auger <eric.auger@redhat.com>
To: eric.auger.pro@gmail.com, eric.auger@redhat.com, hch@lst.de,
m.szyprowski@samsung.com, robin.murphy@arm.com, mst@redhat.com,
jasowang@redhat.com, virtualization@lists.linux-foundation.org,
iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] virtio/virtio_ring: Fix the dma_max_mapping_size call
Date: Mon, 22 Jul 2019 16:55:09 +0200 [thread overview]
Message-ID: <20190722145509.1284-3-eric.auger@redhat.com> (raw)
In-Reply-To: <20190722145509.1284-1-eric.auger@redhat.com>
Do not call dma_max_mapping_size for devices that have no DMA
mask set, otherwise we can hit a NULL pointer dereference.
This occurs when a virtio-blk-pci device is protected with
a virtual IOMMU.
Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
---
drivers/virtio/virtio_ring.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index c8be1c4f5b55..37c143971211 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -262,7 +262,7 @@ size_t virtio_max_dma_size(struct virtio_device *vdev)
{
size_t max_segment_size = SIZE_MAX;
- if (vring_use_dma_api(vdev))
+ if (vring_use_dma_api(vdev) && vdev->dev.dma_mask)
max_segment_size = dma_max_mapping_size(&vdev->dev);
return max_segment_size;
--
2.20.1
next prev parent reply other threads:[~2019-07-22 14:55 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-22 14:55 [PATCH 0/2] Fix NULL pointer dereference with virtio-blk-pci and virtual IOMMU Eric Auger
2019-07-22 14:55 ` [PATCH 1/2] dma-mapping: Protect dma_addressing_limited against NULL dma_mask Eric Auger
2019-07-22 15:26 ` Christoph Hellwig
2019-07-22 15:46 ` Auger Eric
2019-07-22 14:55 ` Eric Auger [this message]
2019-07-22 15:27 ` [PATCH 2/2] virtio/virtio_ring: Fix the dma_max_mapping_size call Christoph Hellwig
2019-07-22 15:39 ` Michael S. Tsirkin
2019-07-22 15:33 ` Michael S. Tsirkin
2019-07-23 15:38 ` Christoph Hellwig
2019-07-23 15:47 ` Michael S. Tsirkin
2019-07-22 15:36 ` Robin Murphy
2019-07-22 15:45 ` Michael S. Tsirkin
2019-07-23 15:38 ` Christoph Hellwig
2019-07-24 22:10 ` Michael S. Tsirkin
2019-07-25 5:25 ` Christoph Hellwig
2019-07-25 11:53 ` Auger Eric
2019-07-25 13:04 ` Christoph Hellwig
2019-07-25 16:32 ` Auger Eric
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190722145509.1284-3-eric.auger@redhat.com \
--to=eric.auger@redhat.com \
--cc=eric.auger.pro@gmail.com \
--cc=hch@lst.de \
--cc=iommu@lists.linux-foundation.org \
--cc=jasowang@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=m.szyprowski@samsung.com \
--cc=mst@redhat.com \
--cc=robin.murphy@arm.com \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).