| Message ID | 20191021201848.4231-1-navid.emamdoost@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | clocksource/drivers: Fix memory leak in ttc_setup_clockevent | expand |
> In the impelementation of ttc_setup_clockevent() the allocated memory > for ttcce should be released if clk_notifier_register() fails. * Please avoid the copying of typos from previous change descriptions. * Under which circumstances will an “imperative mood” matter for you here? https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n151 > +++ b/drivers/clocksource/timer-cadence-ttc.c > @@ -424,6 +424,7 @@ static int __init ttc_setup_clockevent(struct clk *clk, > &ttcce->ttc.clk_rate_change_nb); > if (err) { > pr_warn("Unable to register clock notifier.\n"); > + kfree(ttcce); > return err; > } This addition looks correct. But I would prefer to move such exception handling code to the end of this function implementation so that duplicate source code will be reduced. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n450 Regards, Markus
On 22. 10. 19 10:26, Markus Elfring wrote: >> In the impelementation of ttc_setup_clockevent() the allocated memory >> for ttcce should be released if clk_notifier_register() fails. > > * Please avoid the copying of typos from previous change descriptions. > > * Under which circumstances will an “imperative mood” matter for you here? > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n151 > > >> +++ b/drivers/clocksource/timer-cadence-ttc.c >> @@ -424,6 +424,7 @@ static int __init ttc_setup_clockevent(struct clk *clk, >> &ttcce->ttc.clk_rate_change_nb); >> if (err) { >> pr_warn("Unable to register clock notifier.\n"); >> + kfree(ttcce); >> return err; >> } > > This addition looks correct. > But I would prefer to move such exception handling code to the end of > this function implementation so that duplicate source code will be reduced. > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n450 Just a note. Maybe you should also consider to fix this error path in ttc_setup_clocksource() when notifier also can fail that there is no need to continue with code execution. Thanks, Michal
Thanks for the feedback, I updated this patch and sent v2. Also, I submitted a patch to fix the error handling path in ttc_setup_clocksource(). Here is the link to it: https://lore.kernel.org/patchwork/patch/1143242/ On Tue, Oct 22, 2019 at 3:51 AM Michal Simek <michal.simek@xilinx.com> wrote: > > On 22. 10. 19 10:26, Markus Elfring wrote: > >> In the impelementation of ttc_setup_clockevent() the allocated memory > >> for ttcce should be released if clk_notifier_register() fails. > > > > * Please avoid the copying of typos from previous change descriptions. > > > > * Under which circumstances will an “imperative mood” matter for you here? > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n151 > > > > > >> +++ b/drivers/clocksource/timer-cadence-ttc.c > >> @@ -424,6 +424,7 @@ static int __init ttc_setup_clockevent(struct clk *clk, > >> &ttcce->ttc.clk_rate_change_nb); > >> if (err) { > >> pr_warn("Unable to register clock notifier.\n"); > >> + kfree(ttcce); > >> return err; > >> } > > > > This addition looks correct. > > But I would prefer to move such exception handling code to the end of > > this function implementation so that duplicate source code will be reduced. > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n450 > > Just a note. Maybe you should also consider to fix this error path in > ttc_setup_clocksource() when notifier also can fail that there is no > need to continue with code execution. > > Thanks, > Michal
diff --git a/drivers/clocksource/timer-cadence-ttc.c b/drivers/clocksource/timer-cadence-ttc.c index 88fe2e9ba9a3..b40fc6581389 100644 --- a/drivers/clocksource/timer-cadence-ttc.c +++ b/drivers/clocksource/timer-cadence-ttc.c @@ -424,6 +424,7 @@ static int __init ttc_setup_clockevent(struct clk *clk, &ttcce->ttc.clk_rate_change_nb); if (err) { pr_warn("Unable to register clock notifier.\n"); + kfree(ttcce); return err; }
In the impelementation of ttc_setup_clockevent() the allocated memory for ttcce should be released if clk_notifier_register() fails. Fixes: 70504f311d4b ("clocksource/drivers/cadence_ttc: Convert init function to return error") Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com> --- drivers/clocksource/timer-cadence-ttc.c | 1 + 1 file changed, 1 insertion(+)