[PATCH v2] drivers: clocksource: fix memory leak in davinci_timer_register

From: Qinrun Dai
Date: Thu Apr 13 2023 - 09:52:14 EST


Smatch reports:
drivers/clocksource/timer-davinci.c:332 davinci_timer_register()
warn: 'base' from ioremap() not released on lines: 274.

Fix this and other potential memory leak problems
by adding a set of corresponding exit lables.

Fixes: 721154f972aa ("clocksource/drivers/davinci: Add support for clockevents")
Signed-off-by: Qinrun Dai <flno@xxxxxxxxxxx>
---
drivers/clocksource/timer-davinci.c | 30 +++++++++++++++++++++++------
1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/clocksource/timer-davinci.c b/drivers/clocksource/timer-davinci.c
index 9996c0542520..b1c248498be4 100644
--- a/drivers/clocksource/timer-davinci.c
+++ b/drivers/clocksource/timer-davinci.c
@@ -257,21 +257,25 @@ int __init davinci_timer_register(struct clk *clk,
resource_size(&timer_cfg->reg),
"davinci-timer")) {
pr_err("Unable to request memory region\n");
- return -EBUSY;
+ rv = -EBUSY;
+ goto exit_clk_disable;
}

base = ioremap(timer_cfg->reg.start, resource_size(&timer_cfg->reg));
if (!base) {
pr_err("Unable to map the register range\n");
- return -ENOMEM;
+ rv = -ENOMEM;
+ goto exit_mem_region;
}

davinci_timer_init(base);
tick_rate = clk_get_rate(clk);

clockevent = kzalloc(sizeof(*clockevent), GFP_KERNEL);
- if (!clockevent)
- return -ENOMEM;
+ if (!clockevent) {
+ rv = -ENOMEM;
+ goto exit_iounmap_base;
+ }

clockevent->dev.name = "tim12";
clockevent->dev.features = CLOCK_EVT_FEAT_ONESHOT;
@@ -296,7 +300,7 @@ int __init davinci_timer_register(struct clk *clk,
"clockevent/tim12", clockevent);
if (rv) {
pr_err("Unable to request the clockevent interrupt\n");
- return rv;
+ goto exit_free_clockevent;
}

davinci_clocksource.dev.rating = 300;
@@ -323,13 +327,27 @@ int __init davinci_timer_register(struct clk *clk,
rv = clocksource_register_hz(&davinci_clocksource.dev, tick_rate);
if (rv) {
pr_err("Unable to register clocksource\n");
- return rv;
+ goto exit_free_irq;
}

sched_clock_register(davinci_timer_read_sched_clock,
DAVINCI_TIMER_CLKSRC_BITS, tick_rate);

return 0;
+
+exit_free_irq:
+ free_irq(timer_cfg->irq[DAVINCI_TIMER_CLOCKEVENT_IRQ].start,
+ clockevent);
+exit_free_clockevent:
+ kfree(clockevent);
+exit_iounmap_base:
+ iounmap(base);
+exit_mem_region:
+ release_mem_region(timer_cfg->reg.start,
+ resource_size(&timer_cfg->reg));
+exit_clk_disable:
+ clk_disable_unprepare(clk);
+ return rv;
}

static int __init of_davinci_timer_register(struct device_node *np)
--
2.37.2