[PATCH] mtd: rawnand: atmel: Fix MCK clock leak in atmel_nand_controller_init()

[Wentao Liang]

atmel_nand_controller_init() takes a reference to the MCK clock with
of_clk_get() and keeps it in nc->mck for the lifetime of the
controller.  If the "atmel,smc" phandle is missing or the SMC regmap
cannot be obtained afterwards, the error path jumps to out_release_dma
which only releases the DMA channel, so the clock reference is leaked.
The callers return the error directly and never run
atmel_nand_controller_cleanup(), where the clock is normally put.

Release the reference on those error paths.  The path on which
of_clk_get() itself fails keeps jumping to out_release_dma, as nc->mck
only holds an error pointer there.

Fixes: f9ce2eddf176 ("mtd: nand: atmel: Add ->setup_data_interface() hooks")
Cc: stable at vger.kernel.org
Signed-off-by: Wentao Liang <vulab at iscas.ac.cn>
---
 drivers/mtd/nand/raw/atmel/nand-controller.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c
index 87d9227f6ecc..d61e84b8bc60 100644
--- a/drivers/mtd/nand/raw/atmel/nand-controller.c
+++ b/drivers/mtd/nand/raw/atmel/nand-controller.c
@@ -2086,7 +2086,7 @@ static int atmel_nand_controller_init(struct atmel_nand_controller *nc,
 	if (!np) {
 		dev_err(dev, "Missing or invalid atmel,smc property\n");
 		ret = -EINVAL;
-		goto out_release_dma;
+		goto out_put_mck;
 	}
 
 	nc->smc = syscon_node_to_regmap(np);
@@ -2094,11 +2094,13 @@ static int atmel_nand_controller_init(struct atmel_nand_controller *nc,
 	if (IS_ERR(nc->smc)) {
 		ret = PTR_ERR(nc->smc);
 		dev_err(dev, "Could not get SMC regmap (err = %d)\n", ret);
-		goto out_release_dma;
+		goto out_put_mck;
 	}
 
 	return 0;
 
+out_put_mck:
+	clk_put(nc->mck);
 out_release_dma:
 	if (nc->dmac)
 		dma_release_channel(nc->dmac);
-- 
2.34.1