4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Minwoo Im <minwoo.im.dev@xxxxxxxxx>
[ Upstream commit 7e5dd57ef3081ff6c03908d786ed5087f6fbb7ae ]
Following condition which will cause NULL pointer dereference will
occur in nvme_free_host_mem() when it tries to remove pci device via
nvme_remove() especially after a failure of host memory allocation for HMB.
"(host_mem_descs == NULL) && (nr_host_mem_descs != 0)"
It's because __nr_host_mem_descs__ is not cleared to 0 unlike
__host_mem_descs__ is so.
Signed-off-by: Minwoo Im <minwoo.im.dev@xxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/nvme/host/pci.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1617,6 +1617,7 @@ static void nvme_free_host_mem(struct nv
dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
dev->host_mem_descs, dev->host_mem_descs_dma);
dev->host_mem_descs = NULL;
+ dev->nr_host_mem_descs = 0;
}
static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,