diff options
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/virtio_blk.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index c3e260d5bdd0..4b49df2dfd23 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -21,6 +21,9 @@ #define VQ_NAME_LEN 16 #define MAX_DISCARD_SEGMENTS 256u +/* The maximum number of sg elements that fit into a virtqueue */ +#define VIRTIO_BLK_MAX_SG_ELEMS 32768 + static int major; static DEFINE_IDA(vd_index_ida); @@ -721,7 +724,10 @@ static int virtblk_probe(struct virtio_device *vdev) if (err || !sg_elems) sg_elems = 1; - /* We need an extra sg elements at head and tail. */ + /* Prevent integer overflows and honor max vq size */ + sg_elems = min_t(u32, sg_elems, VIRTIO_BLK_MAX_SG_ELEMS - 2); + + /* We need extra sg elements at head and tail. */ sg_elems += 2; vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL); if (!vblk) { |