virtio_ring: Fix mem leak with vring_new_virtqueue()

The functions vring_new_virtqueue() and __vring_new_virtqueue() are used
with split rings, and any allocations within these functions are managed
outside of the .we_own_ring flag. The commit cbeedb72b9 ("virtio_ring:
allocate desc state for split ring separately") allocates the desc state
within the __vring_new_virtqueue() but frees it only when the .we_own_ring
flag is set. This leads to a memory leak when freeing such allocated
virtqueues with the vring_del_virtqueue() function.

Fix this by moving the desc_state free code outside the flag and only
for split rings. Issue was discovered during testing with remoteproc
and virtio_rpmsg.

Fixes: cbeedb72b9 ("virtio_ring: allocate desc state for split ring separately")
Signed-off-by: Suman Anna <s-anna@ti.com>
Link: https://lore.kernel.org/r/20200224212643.30672-1-s-anna@ti.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
This commit is contained in:
Suman Anna 2020-02-24 15:26:43 -06:00 коммит произвёл Michael S. Tsirkin
Родитель 98d54f81e3
Коммит f13f09a12c
1 изменённых файлов: 2 добавлений и 2 удалений

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@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq)
vq->split.queue_size_in_bytes,
vq->split.vring.desc,
vq->split.queue_dma_addr);
kfree(vq->split.desc_state);
}
}
if (!vq->packed_ring)
kfree(vq->split.desc_state);
list_del(&_vq->list);
kfree(vq);
}