Re: [PATCH] clocksource/drivers: Fix error handling in ttc_setup_clocksource

From: Navid Emamdoost
Date: Sat Dec 14 2019 - 17:54:55 EST


Would you review this patch, please?

On Tue, Oct 22, 2019 at 11:47 PM Navid Emamdoost
<navid.emamdoost@xxxxxxxxx> wrote:
>
> In the implementation of ttc_setup_clocksource() when
> clk_notifier_register() fails the execution should go to error handling.
> Additionally, to avoid memory leak the allocated memory for ttccs should
> be released, too. So, goto error handling to release the memory and
> return.
>
> Fixes: e932900a3279 ("arm: zynq: Use standard timer binding")
> Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx>
> ---
> drivers/clocksource/timer-cadence-ttc.c | 20 +++++++++++---------
> 1 file changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/clocksource/timer-cadence-ttc.c b/drivers/clocksource/timer-cadence-ttc.c
> index 88fe2e9ba9a3..035e16bc17d3 100644
> --- a/drivers/clocksource/timer-cadence-ttc.c
> +++ b/drivers/clocksource/timer-cadence-ttc.c
> @@ -328,10 +328,8 @@ static int __init ttc_setup_clocksource(struct clk *clk, void __iomem *base,
> ttccs->ttc.clk = clk;
>
> err = clk_prepare_enable(ttccs->ttc.clk);
> - if (err) {
> - kfree(ttccs);
> - return err;
> - }
> + if (err)
> + goto release_ttccs;
>
> ttccs->ttc.freq = clk_get_rate(ttccs->ttc.clk);
>
> @@ -341,8 +339,10 @@ static int __init ttc_setup_clocksource(struct clk *clk, void __iomem *base,
>
> err = clk_notifier_register(ttccs->ttc.clk,
> &ttccs->ttc.clk_rate_change_nb);
> - if (err)
> + if (err) {
> pr_warn("Unable to register clock notifier.\n");
> + goto release_ttccs;
> + }
>
> ttccs->ttc.base_addr = base;
> ttccs->cs.name = "ttc_clocksource";
> @@ -363,16 +363,18 @@ static int __init ttc_setup_clocksource(struct clk *clk, void __iomem *base,
> ttccs->ttc.base_addr + TTC_CNT_CNTRL_OFFSET);
>
> err = clocksource_register_hz(&ttccs->cs, ttccs->ttc.freq / PRESCALE);
> - if (err) {
> - kfree(ttccs);
> - return err;
> - }
> + if (err)
> + goto release_ttccs;
>
> ttc_sched_clock_val_reg = base + TTC_COUNT_VAL_OFFSET;
> sched_clock_register(ttc_sched_clock_read, timer_width,
> ttccs->ttc.freq / PRESCALE);
>
> return 0;
> +
> +release_ttccs:
> + kfree(ttccs);
> + return err;
> }
>
> static int ttc_rate_change_clockevent_cb(struct notifier_block *nb,
> --
> 2.17.1
>


--
Navid.