[PATCH] clocksource/drivers/nomadik-mtu: fix resource leak on init error paths

[Haotian Zhang]

nmdk_timer_of_init() maps the registers with of_iomap() and acquires the
"apb_pclk" and "timclk" clocks with of_clk_get_by_name(), but every error
path after that returns directly without releasing them. When the clock
lookups or irq_of_parse_and_map() fail, the iomap mapping and any already
obtained clock references are leaked.

Add rollback labels that put the clocks and unmap the registers on each
failure path.

Fixes: e46105aff5e5 ("clocksource/drivers/nomadik-mtu: Convert init function to return error")
Assisted-by: DeepSeek-V4.1-Flash
Signed-off-by: Haotian Zhang <vulab@xxxxxxxxxxx>
---
 drivers/clocksource/nomadik-mtu.c | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/nomadik-mtu.c b/drivers/clocksource/nomadik-mtu.c
index 53d0159cc6be..04740793da74 100644
--- a/drivers/clocksource/nomadik-mtu.c
+++ b/drivers/clocksource/nomadik-mtu.c
@@ -252,6 +252,7 @@ static int __init nmdk_timer_of_init(struct device_node *node)
 	struct clk *clk;
 	void __iomem *base;
 	int irq;
+	int ret;
 
 	base = of_iomap(node, 0);
 	if (!base) {
@@ -262,22 +263,33 @@ static int __init nmdk_timer_of_init(struct device_node *node)
 	pclk = of_clk_get_by_name(node, "apb_pclk");
 	if (IS_ERR(pclk)) {
 		pr_err("could not get apb_pclk\n");
-		return PTR_ERR(pclk);
+		ret = PTR_ERR(pclk);
+		goto out_iounmap;
 	}
 
 	clk = of_clk_get_by_name(node, "timclk");
 	if (IS_ERR(clk)) {
 		pr_err("could not get timclk\n");
-		return PTR_ERR(clk);
+		ret = PTR_ERR(clk);
+		goto out_clk_put_pclk;
 	}
 
 	irq = irq_of_parse_and_map(node, 0);
 	if (irq <= 0) {
 		pr_err("Can't parse IRQ\n");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_clk_put;
 	}
 
 	return nmdk_timer_init(base, irq, pclk, clk);
+
+out_clk_put:
+	clk_put(clk);
+out_clk_put_pclk:
+	clk_put(pclk);
+out_iounmap:
+	iounmap(base);
+	return ret;
 }
 TIMER_OF_DECLARE(nomadik_mtu, "st,nomadik-mtu",
 		       nmdk_timer_of_init);
-- 
2.25.1