6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Christoph Hellwig <hch@xxxxxx>
[ 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@xxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 b701969cf1c2a..e0b502573b427 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -153,6 +153,7 @@ 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;
@@ -1929,10 +1930,10 @@ 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;
}
@@ -1940,7 +1941,7 @@ 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;
@@ -1953,8 +1954,9 @@ 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;
@@ -1983,6 +1985,7 @@ 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;
@@ -1997,8 +2000,7 @@ 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;
--
2.43.0
