From: Xuan Zhuo xuanzhuo@linux.alibaba.com
[ Upstream commit fc6d70f40b3d0b3219e2026d05be0409695f620d ]
When using indirect with packed, we don't check for allocation failures. This patch checks that and fall back on direct.
Fixes: 1ce9e6055fa0 ("virtio_ring: introduce packed ring support") Signed-off-by: Xuan Zhuo xuanzhuo@linux.alibaba.com Link: https://lore.kernel.org/r/20211020112323.67466-3-xuanzhuo@linux.alibaba.com Signed-off-by: Michael S. Tsirkin mst@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/virtio/virtio_ring.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 3035bb6f54585..d1f47327f6cfe 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -1065,6 +1065,8 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
head = vq->packed.next_avail_idx; desc = alloc_indirect_packed(total_sg, gfp); + if (!desc) + return -ENOMEM;
if (unlikely(vq->vq.num_free < 1)) { pr_debug("Can't add buf len 1 - avail = 0\n"); @@ -1176,6 +1178,7 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq, unsigned int i, n, c, descs_used, err_idx; __le16 head_flags, flags; u16 head, id, prev, curr, avail_used_flags; + int err;
START_USE(vq);
@@ -1191,9 +1194,14 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
BUG_ON(total_sg == 0);
- if (virtqueue_use_indirect(_vq, total_sg)) - return virtqueue_add_indirect_packed(vq, sgs, total_sg, - out_sgs, in_sgs, data, gfp); + if (virtqueue_use_indirect(_vq, total_sg)) { + err = virtqueue_add_indirect_packed(vq, sgs, total_sg, out_sgs, + in_sgs, data, gfp); + if (err != -ENOMEM) + return err; + + /* fall back on direct */ + }
head = vq->packed.next_avail_idx; avail_used_flags = vq->packed.avail_used_flags;