[tip: timers/urgent] timekeeping: Fix resource leak in tk_aux_sysfs_init() error paths

["tip-bot2 for Malaya Kumar Rout" <tip-bot2@linutronix.de>]

The following commit has been merged into the timers/urgent branch of tip:

Commit-ID:     7b5ab04f035f829ed6008e4685501ec00b3e73c9
Gitweb:        https://git.kernel.org/tip/7b5ab04f035f829ed6008e4685501ec00b3e73c9
Author:        Malaya Kumar Rout <mrout@redhat.com>
AuthorDate:    Thu, 20 Nov 2025 20:32:13 +05:30
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 20 Nov 2025 16:40:48 +01:00

timekeeping: Fix resource leak in tk_aux_sysfs_init() error paths

tk_aux_sysfs_init() returns immediately on error during the auxiliary clock
initialization loop without cleaning up previously allocated kobjects and
sysfs groups.

If kobject_create_and_add() or sysfs_create_group() fails during loop
iteration, the parent kobjects (tko and auxo) and any previously created
child kobjects are leaked.

Fix this by adding proper error handling with goto labels to ensure all
allocated resources are cleaned up on failure. kobject_put() on the
parent kobjects will handle cleanup of their children.

Fixes: 7b95663a3d96 ("timekeeping: Provide interface to control auxiliary clocks")
Signed-off-by: Malaya Kumar Rout <mrout@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251120150213.246777-1-mrout@redhat.com
---
 kernel/time/timekeeping.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 3a4d3b2..08e0943 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -3060,29 +3060,32 @@ static const struct attribute_group aux_clock_enable_attr_group = {
 static int __init tk_aux_sysfs_init(void)
 {
 	struct kobject *auxo, *tko = kobject_create_and_add("time", kernel_kobj);
+	int ret = -ENOMEM;
 
 	if (!tko)
-		return -ENOMEM;
+		return ret;
 
 	auxo = kobject_create_and_add("aux_clocks", tko);
-	if (!auxo) {
-		kobject_put(tko);
-		return -ENOMEM;
-	}
+	if (!auxo)
+		goto err_clean;
 
 	for (int i = 0; i < MAX_AUX_CLOCKS; i++) {
 		char id[2] = { [0] = '0' + i, };
 		struct kobject *clk = kobject_create_and_add(id, auxo);
 
 		if (!clk)
-			return -ENOMEM;
-
-		int ret = sysfs_create_group(clk, &aux_clock_enable_attr_group);
+			goto err_clean;
 
+		ret = sysfs_create_group(clk, &aux_clock_enable_attr_group);
 		if (ret)
-			return ret;
+			goto err_clean;
 	}
 	return 0;
+
+err_clean:
+	kobject_put(auxo);
+	kobject_put(tko);
+	return ret;
 }
 late_initcall(tk_aux_sysfs_init);