5.4-stable review patch. If anyone has any objections, please let me know.
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From: Christoph Hellwig hch@lst.de
[ Upstream commit 3c2fb1ca8086eb139b2a551358137525ae8e0d7a ]
The HMB descriptor table is sized to the maximum number of descriptors that could be used for a given device, but __nvme_alloc_host_mem could break out of the loop earlier on memory allocation failure and end up using less descriptors than planned for, which leads to an incorrect size passed to dma_free_coherent.
In practice this was not showing up because the number of descriptors tends to be low and the dma coherent allocator always allocates and frees at least a page.
Fixes: 87ad72a59a38 ("nvme-pci: implement host memory buffer support") Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/pci.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 20f5616fd5182..11df63d214900 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -125,6 +125,7 @@ struct nvme_dev { /* host memory buffer support: */ u64 host_mem_size; u32 nr_host_mem_descs; + u32 host_mem_descs_size; dma_addr_t host_mem_descs_dma; struct nvme_host_mem_buf_desc *host_mem_descs; void **host_mem_desc_bufs; @@ -1924,10 +1925,10 @@ static void nvme_free_host_mem(struct nvme_dev *dev)
kfree(dev->host_mem_desc_bufs); dev->host_mem_desc_bufs = NULL; - dma_free_coherent(dev->dev, - dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs), + dma_free_coherent(dev->dev, dev->host_mem_descs_size, dev->host_mem_descs, dev->host_mem_descs_dma); dev->host_mem_descs = NULL; + dev->host_mem_descs_size = 0; dev->nr_host_mem_descs = 0; }
@@ -1935,7 +1936,7 @@ static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred, u32 chunk_size) { struct nvme_host_mem_buf_desc *descs; - u32 max_entries, len; + u32 max_entries, len, descs_size; dma_addr_t descs_dma; int i = 0; void **bufs; @@ -1948,8 +1949,9 @@ static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred, if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries) max_entries = dev->ctrl.hmmaxd;
- descs = dma_alloc_coherent(dev->dev, max_entries * sizeof(*descs), - &descs_dma, GFP_KERNEL); + descs_size = max_entries * sizeof(*descs); + descs = dma_alloc_coherent(dev->dev, descs_size, &descs_dma, + GFP_KERNEL); if (!descs) goto out;
@@ -1978,6 +1980,7 @@ static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred, dev->host_mem_size = size; dev->host_mem_descs = descs; dev->host_mem_descs_dma = descs_dma; + dev->host_mem_descs_size = descs_size; dev->host_mem_desc_bufs = bufs; return 0;
@@ -1992,8 +1995,7 @@ static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
kfree(bufs); out_free_descs: - dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs, - descs_dma); + dma_free_coherent(dev->dev, descs_size, descs, descs_dma); out: dev->host_mem_descs = NULL; return -ENOMEM;