clk: imx: imx6q: Fix device node reference leak in pll6_bypassed()

[PATCH] clk: imx: imx6q: Fix device node reference leak in pll6_bypassed()

Posted by Felix Gu 1 week ago

The function pll6_bypassed() calls of_parse_phandle_with_args()
but never calls of_node_put() to release the reference, causing
a memory leak.

Fix this by adding proper cleanup calls on all exit paths.

Fixes: 3cc48976e9763 ("clk: imx6q: handle ENET PLL bypass")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
---
 drivers/clk/imx/clk-imx6q.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
index bf4c1d9c9928..1d8e8f0891a3 100644
--- a/drivers/clk/imx/clk-imx6q.c
+++ b/drivers/clk/imx/clk-imx6q.c
@@ -238,8 +238,11 @@ static bool pll6_bypassed(struct device_node *node)
 			return false;
 
 		if (clkspec.np == node &&
-		    clkspec.args[0] == IMX6QDL_PLL6_BYPASS)
+		    clkspec.args[0] == IMX6QDL_PLL6_BYPASS) {
+			of_node_put(clkspec.np);
 			break;
+		}
+		of_node_put(clkspec.np);
 	}
 
 	/* PLL6 bypass is not part of the assigned clock list */
@@ -249,6 +252,7 @@ static bool pll6_bypassed(struct device_node *node)
 	ret = of_parse_phandle_with_args(node, "assigned-clock-parents",
 					 "#clock-cells", index, &clkspec);
 
+	of_node_put(clkspec.np);
 	if (clkspec.args[0] != IMX6QDL_CLK_PLL6)
 		return true;
 

---
base-commit: 33a647c659ffa5bdb94abc345c8c86768ff96215
change-id: 20260130-clk-imx6q-9c4b8835fc26

Best regards,
-- 
Felix Gu <ustc.gu@gmail.com>

Re: [PATCH] clk: imx: imx6q: Fix device node reference leak in pll6_bypassed()

Posted by Frank Li 1 week ago

On Fri, Jan 30, 2026 at 11:56:28PM +0800, Felix Gu wrote:
> The function pll6_bypassed() calls of_parse_phandle_with_args()
> but never calls of_node_put() to release the reference, causing
> a memory leak.
>
> Fix this by adding proper cleanup calls on all exit paths.
>
> Fixes: 3cc48976e9763 ("clk: imx6q: handle ENET PLL bypass")
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>
> ---
>  drivers/clk/imx/clk-imx6q.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
> index bf4c1d9c9928..1d8e8f0891a3 100644
> --- a/drivers/clk/imx/clk-imx6q.c
> +++ b/drivers/clk/imx/clk-imx6q.c
> @@ -238,8 +238,11 @@ static bool pll6_bypassed(struct device_node *node)
>  			return false;
>
>  		if (clkspec.np == node &&
> -		    clkspec.args[0] == IMX6QDL_PLL6_BYPASS)
> +		    clkspec.args[0] == IMX6QDL_PLL6_BYPASS) {
> +			of_node_put(clkspec.np);
>  			break;
> +		}
> +		of_node_put(clkspec.np);


I think you put of_node_put() before if branch

rc = of_parse_phandle_with_args()
if (rc < 0)
	...
of_node_put(clkspec.np);


There are more places call of_parse_phandle_with_args() without of_node_put().


>  	}
>
>  	/* PLL6 bypass is not part of the assigned clock list */
> @@ -249,6 +252,7 @@ static bool pll6_bypassed(struct device_node *node)
>  	ret = of_parse_phandle_with_args(node, "assigned-clock-parents",
>  					 "#clock-cells", index, &clkspec);
>

this one miss check ret;

Frank
> +	of_node_put(clkspec.np);
>  	if (clkspec.args[0] != IMX6QDL_CLK_PLL6)
>  		return true;
>
>
> ---
> base-commit: 33a647c659ffa5bdb94abc345c8c86768ff96215
> change-id: 20260130-clk-imx6q-9c4b8835fc26
>
> Best regards,
> --
> Felix Gu <ustc.gu@gmail.com>
>

Re: [PATCH] clk: imx: imx6q: Fix device node reference leak in pll6_bypassed()

Posted by Felix Gu 1 week ago

On Sat, Jan 31, 2026 at 1:37 AM Frank Li <Frank.li@nxp.com> wrote:
>
> On Fri, Jan 30, 2026 at 11:56:28PM +0800, Felix Gu wrote:
> > The function pll6_bypassed() calls of_parse_phandle_with_args()
> > but never calls of_node_put() to release the reference, causing
> > a memory leak.
> >
> > Fix this by adding proper cleanup calls on all exit paths.
> >
> > Fixes: 3cc48976e9763 ("clk: imx6q: handle ENET PLL bypass")
> > Signed-off-by: Felix Gu <ustc.gu@gmail.com>
> > ---
> >  drivers/clk/imx/clk-imx6q.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
> > index bf4c1d9c9928..1d8e8f0891a3 100644
> > --- a/drivers/clk/imx/clk-imx6q.c
> > +++ b/drivers/clk/imx/clk-imx6q.c
> > @@ -238,8 +238,11 @@ static bool pll6_bypassed(struct device_node *node)
> >                       return false;
> >
> >               if (clkspec.np == node &&
> > -                 clkspec.args[0] == IMX6QDL_PLL6_BYPASS)
> > +                 clkspec.args[0] == IMX6QDL_PLL6_BYPASS) {
> > +                     of_node_put(clkspec.np);
> >                       break;
> > +             }
> > +             of_node_put(clkspec.np);
>
>
> I think you put of_node_put() before if branch
I didn't put of_node_put() before if branch is clksepc.np is used in
the if branch.
It maybe not good to use it after calling of_node_put().
>
> rc = of_parse_phandle_with_args()
> if (rc < 0)
>         ...
> of_node_put(clkspec.np);
>
>
> There are more places call of_parse_phandle_with_args() without of_node_put().
Thanks, I missed that, I will fix it in V2.

Best regards,
Felix Gu
>
>
> >       }
> >
> >       /* PLL6 bypass is not part of the assigned clock list */
> > @@ -249,6 +252,7 @@ static bool pll6_bypassed(struct device_node *node)
> >       ret = of_parse_phandle_with_args(node, "assigned-clock-parents",
> >                                        "#clock-cells", index, &clkspec);
> >
>
> this one miss check ret;
>
> Frank
> > +     of_node_put(clkspec.np);
> >       if (clkspec.args[0] != IMX6QDL_CLK_PLL6)
> >               return true;
> >
> >
> > ---
> > base-commit: 33a647c659ffa5bdb94abc345c8c86768ff96215
> > change-id: 20260130-clk-imx6q-9c4b8835fc26
> >
> > Best regards,
> > --
> > Felix Gu <ustc.gu@gmail.com>
> >