Re: [PATCH] m68k: let clk_enable() return immediately if clk is NULL

From: Greg Ungerer
Date: Tue Jan 26 2021 - 01:20:10 EST


Hi Defang,

On 28/12/20 12:07 pm, Defang Bo wrote:
Similar to commit<742859adc721>("m68k: let clk_disable() return immediately if clk is NULL").
there should be a check for clk to prevent NULL pointer dereference.

Signed-off-by: Defang Bo <bodefang@xxxxxxx>

I have applied this to the m68knommu git tree, for-next branch -
with blank line added as per Geert's suggestion.

Regards
Greg



---
arch/m68k/coldfire/clk.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/m68k/coldfire/clk.c b/arch/m68k/coldfire/clk.c
index 7bc666e..6decd11 100644
--- a/arch/m68k/coldfire/clk.c
+++ b/arch/m68k/coldfire/clk.c
@@ -90,6 +90,9 @@ EXPORT_SYMBOL(clk_get);
int clk_enable(struct clk *clk)
{
unsigned long flags;
+ if (!clk)
+ return -EINVAL;
+
spin_lock_irqsave(&clk_lock, flags);
if ((clk->enabled++ == 0) && clk->clk_ops)
clk->clk_ops->enable(clk);