[PATCH 5.8 026/124] nvme-core: put ctrl ref when module ref get fail

From: Greg Kroah-Hartman
Date: Mon Oct 12 2020 - 09:55:16 EST


From: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>

commit 4bab69093044ca81f394bd0780be1b71c5a4d308 upstream.

When try_module_get() fails in the nvme_dev_open() it returns without
releasing the ctrl reference which was taken earlier.

Put the ctrl reference which is taken before calling the
try_module_get() in the error return code path.

Fixes: 52a3974feb1a "nvme-core: get/put ctrl and transport module in nvme_dev_open/release()"
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/nvme/host/core.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3061,8 +3061,10 @@ static int nvme_dev_open(struct inode *i
}

nvme_get_ctrl(ctrl);
- if (!try_module_get(ctrl->ops->module))
+ if (!try_module_get(ctrl->ops->module)) {
+ nvme_put_ctrl(ctrl);
return -EINVAL;
+ }

file->private_data = ctrl;
return 0;