[PATCH 4.9 50/72] nvmem: core: fix leaks on registration errors

From: Greg Kroah-Hartman
Date: Wed Jul 19 2017 - 06:32:21 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@xxxxxxxxxx>

commit 3360acdf839170b612f5b212539694c20e3f16d0 upstream.

Make sure to deregister and release the nvmem device and underlying
memory on registration errors.

Note that the private data must be freed using put_device() once the
struct device has been initialised.

Also note that there's a related reference leak in the deregistration
function as reported by Mika Westerberg which is being fixed separately.

Fixes: b6c217ab9be6 ("nvmem: Add backwards compatibility support for older EEPROM drivers.")
Fixes: eace75cfdcf7 ("nvmem: Add a simple NVMEM framework for nvmem providers")
Cc: Andrew Lunn <andrew@xxxxxxx>
Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Cc: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Acked-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/nvmem/core.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -488,21 +488,24 @@ struct nvmem_device *nvmem_register(cons

rval = device_add(&nvmem->dev);
if (rval)
- goto out;
+ goto err_put_device;

if (config->compat) {
rval = nvmem_setup_compat(nvmem, config);
if (rval)
- goto out;
+ goto err_device_del;
}

if (config->cells)
nvmem_add_cells(nvmem, config);

return nvmem;
-out:
- ida_simple_remove(&nvmem_ida, nvmem->id);
- kfree(nvmem);
+
+err_device_del:
+ device_del(&nvmem->dev);
+err_put_device:
+ put_device(&nvmem->dev);
+
return ERR_PTR(rval);
}
EXPORT_SYMBOL_GPL(nvmem_register);