[PATCH 2/3] clk: Prevent a hanging pointer being abused

[Charles Manning <cdhmanning@gmail.com>]

Clock init structs are normally created on the stack.

If the pointer is left intact after clk_register then there is
opportunity for clk drivers to dereference the pointer.

This was causing a problem in socfpga/clk.c for instance.

Better to NULL out the pointer so it can't be abused.

Signed-off-by: Charles Manning <cdhmanning@gmail.com>
---
 drivers/clk/clk.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index ec41922..9e92170 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1973,6 +1973,10 @@ struct clk *__clk_register(struct device *dev, struct clk_hw *hw)
 		clk->owner = NULL;
 
 	ret = __clk_init(dev, clk);
+
+	/* Prevent a hanging pointer being left around. */
+	hw->init = NULL;
+
 	if (ret)
 		return ERR_PTR(ret);
 
-- 
1.9.1