Xuan Zhuo
2021-Sep-27 03:06 UTC
[PATCH] virtio_ring: check desc == NULL when packed and indirect
In the case of packed, use indirect desc, since desc is allocated by
kmalloc_array(), we should check whether its return value is NULL.
Fixes: 1ce9e6055fa ("virtio_ring: introduce packed ring support")
Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
drivers/virtio/virtio_ring.c | 27 ++++++++++++++++-----------
1 file changed, 16 insertions(+), 11 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index dd95dfd85e98..7dd381eae725 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1050,21 +1050,20 @@ static struct vring_packed_desc
*alloc_indirect_packed(unsigned int total_sg,
}
static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
- struct scatterlist *sgs[],
- unsigned int total_sg,
- unsigned int out_sgs,
- unsigned int in_sgs,
- void *data,
- gfp_t gfp)
+ struct scatterlist *sgs[],
+ struct vring_packed_desc *desc,
+ unsigned int total_sg,
+ unsigned int out_sgs,
+ unsigned int in_sgs,
+ void *data,
+ gfp_t gfp)
{
- struct vring_packed_desc *desc;
struct scatterlist *sg;
unsigned int i, n, err_idx;
u16 head, id;
dma_addr_t addr;
head = vq->packed.next_avail_idx;
- desc = alloc_indirect_packed(total_sg, gfp);
if (unlikely(vq->vq.num_free < 1)) {
pr_debug("Can't add buf len 1 - avail = 0\n");
@@ -1191,9 +1190,15 @@ 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)) {
+ desc = alloc_indirect_packed(total_sg, gfp);
+ if (desc) {
+ return virtqueue_add_indirect_packed(vq, sgs, desc,
+ total_sg,
+ out_sgs, in_sgs,
+ data, gfp);
+ }
+ }
head = vq->packed.next_avail_idx;
avail_used_flags = vq->packed.avail_used_flags;
--
2.31.0
Jason Wang
2021-Sep-27 03:20 UTC
[PATCH] virtio_ring: check desc == NULL when packed and indirect
On Mon, Sep 27, 2021 at 11:06 AM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote:> > In the case of packed, use indirect desc, since desc is allocated by > kmalloc_array(), we should check whether its return value is NULL. > > Fixes: 1ce9e6055fa ("virtio_ring: introduce packed ring support") > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/virtio/virtio_ring.c | 27 ++++++++++++++++----------- > 1 file changed, 16 insertions(+), 11 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index dd95dfd85e98..7dd381eae725 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -1050,21 +1050,20 @@ static struct vring_packed_desc *alloc_indirect_packed(unsigned int total_sg, > } > > static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, > - struct scatterlist *sgs[], > - unsigned int total_sg, > - unsigned int out_sgs, > - unsigned int in_sgs, > - void *data, > - gfp_t gfp) > + struct scatterlist *sgs[], > + struct vring_packed_desc *desc, > + unsigned int total_sg, > + unsigned int out_sgs, > + unsigned int in_sgs, > + void *data, > + gfp_t gfp)It looks to me the style changes are mixed with bug fix here.> { > - struct vring_packed_desc *desc; > struct scatterlist *sg; > unsigned int i, n, err_idx; > u16 head, id; > dma_addr_t addr; > > head = vq->packed.next_avail_idx; > - desc = alloc_indirect_packed(total_sg, gfp); > > if (unlikely(vq->vq.num_free < 1)) { > pr_debug("Can't add buf len 1 - avail = 0\n"); > @@ -1191,9 +1190,15 @@ 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)) { > + desc = alloc_indirect_packed(total_sg, gfp); > + if (desc) { > + return virtqueue_add_indirect_packed(vq, sgs, desc, > + total_sg, > + out_sgs, in_sgs, > + data, gfp); > + } > + }Any reason that we can't fix virtqueue_add_indirect_packed()? It can help to reduce the changeset and ease the backport. Thanks> > head = vq->packed.next_avail_idx; > avail_used_flags = vq->packed.avail_used_flags; > -- > 2.31.0 >
Michael S. Tsirkin
2021-Sep-27 09:36 UTC
[PATCH] virtio_ring: check desc == NULL when packed and indirect
On Mon, Sep 27, 2021 at 11:06:18AM +0800, Xuan Zhuo wrote:> In the case of packed, use indirect desc, since desc is allocated by > kmalloc_array(), we should check whether its return value is NULL. > > Fixes: 1ce9e6055fa ("virtio_ring: introduce packed ring support") > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/virtio/virtio_ring.c | 27 ++++++++++++++++----------- > 1 file changed, 16 insertions(+), 11 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index dd95dfd85e98..7dd381eae725 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -1050,21 +1050,20 @@ static struct vring_packed_desc *alloc_indirect_packed(unsigned int total_sg, > } > > static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, > - struct scatterlist *sgs[], > - unsigned int total_sg, > - unsigned int out_sgs, > - unsigned int in_sgs, > - void *data, > - gfp_t gfp) > + struct scatterlist *sgs[], > + struct vring_packed_desc *desc, > + unsigned int total_sg, > + unsigned int out_sgs, > + unsigned int in_sgs, > + void *data, > + gfp_t gfp) > { > - struct vring_packed_desc *desc; > struct scatterlist *sg; > unsigned int i, n, err_idx; > u16 head, id; > dma_addr_t addr; > > head = vq->packed.next_avail_idx; > - desc = alloc_indirect_packed(total_sg, gfp); > > if (unlikely(vq->vq.num_free < 1)) { > pr_debug("Can't add buf len 1 - avail = 0\n"); > @@ -1191,9 +1190,15 @@ 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)) { > + desc = alloc_indirect_packed(total_sg, gfp); > + if (desc) { > + return virtqueue_add_indirect_packed(vq, sgs, desc, > + total_sg, > + out_sgs, in_sgs, > + data, gfp); > + }Eschew {} for a single statement if conditions pls.> + } > > head = vq->packed.next_avail_idx; > avail_used_flags = vq->packed.avail_used_flags; > -- > 2.31.0