[PATCH] mtd: rawnand: fsl_ifc: allocate shared ctrl with devm_kzalloc

[Rosen Penev]

Allocate the shared fsl_ifc_nand_ctrl structure against the controller
device, which outlives all NAND child devices, so it is freed
automatically.  This drops the manual kfree() and the broken chip
counter that was decremented in remove() but never incremented
anywhere, leaking the structure and leaving the freed pointer in
ctrl->nand on re-probe.

Assisted-by: opencode:big-pickle
Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
---
 drivers/mtd/nand/raw/fsl_ifc_nand.c | 15 ++-------------
 1 file changed, 2 insertions(+), 13 deletions(-)

diff --git a/drivers/mtd/nand/raw/fsl_ifc_nand.c b/drivers/mtd/nand/raw/fsl_ifc_nand.c
index b34524726dec..db6bb0bb43e8 100644
--- a/drivers/mtd/nand/raw/fsl_ifc_nand.c
+++ b/drivers/mtd/nand/raw/fsl_ifc_nand.c
@@ -48,7 +48,6 @@ struct fsl_ifc_nand_ctrl {
 	unsigned int index;	/* Pointer to next byte to 'read'	*/
 	unsigned int oob;	/* Non zero if operating on OOB data	*/
 	unsigned int eccread;	/* Non zero for a full-page ECC read	*/
-	unsigned int counter;	/* counter for the initializations	*/
 	unsigned int max_bitflips;  /* Saved during READ0 cmd		*/
 };
 
@@ -1034,15 +1033,13 @@ static int fsl_ifc_nand_probe(struct platform_device *dev)
 
 	mutex_lock(&fsl_ifc_nand_mutex);
 	if (!ctrl->nand) {
-		ifc_nand_ctrl = kzalloc_obj(*ifc_nand_ctrl);
+		ifc_nand_ctrl = devm_kzalloc(ctrl->dev, sizeof(*ifc_nand_ctrl),
+					     GFP_KERNEL);
 		if (!ifc_nand_ctrl) {
 			mutex_unlock(&fsl_ifc_nand_mutex);
 			return -ENOMEM;
 		}
 
-		ifc_nand_ctrl->read_bytes = 0;
-		ifc_nand_ctrl->index = 0;
-		ifc_nand_ctrl->addr = NULL;
 		ctrl->nand = ifc_nand_ctrl;
 
 		nand_controller_init(&ifc_nand_ctrl->controller);
@@ -1122,14 +1119,6 @@ static void fsl_ifc_nand_remove(struct platform_device *dev)
 	nand_cleanup(chip);
 
 	fsl_ifc_chip_remove(priv);
-
-	mutex_lock(&fsl_ifc_nand_mutex);
-	ifc_nand_ctrl->counter--;
-	if (!ifc_nand_ctrl->counter) {
-		priv->ctrl->nand = NULL;
-		kfree(ifc_nand_ctrl);
-	}
-	mutex_unlock(&fsl_ifc_nand_mutex);
 }
 
 static const struct of_device_id fsl_ifc_nand_match[] = {
-- 
2.55.0