[PATCH] cgroup/cpuset: Free sched domains on rebuild guard failure

[Guopeng Zhang <guopeng.zhang@linux.dev>]

From: Guopeng Zhang <zhangguopeng@kylinos.cn>

generate_sched_domains() returns sched-domain masks and optional
attributes that are normally handed to partition_sched_domains(), which
takes ownership of them.

rebuild_sched_domains_locked() has a WARN guard after
generate_sched_domains() and before partition_sched_domains() to avoid
passing offline CPUs into the scheduler domain rebuild path. If that
guard fires, the function currently returns directly without freeing
the generated doms and attr.

Free the generated sched-domain masks and attributes before returning
from the guard failure path.

Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn>
---
 kernel/cgroup/cpuset.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 51327333980a..c5fdebc205d8 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1004,8 +1004,11 @@ void rebuild_sched_domains_locked(void)
 	* prevent the panic.
 	*/
 	for (i = 0; doms && i < ndoms; i++) {
-		if (WARN_ON_ONCE(!cpumask_subset(doms[i], cpu_active_mask)))
+		if (WARN_ON_ONCE(!cpumask_subset(doms[i], cpu_active_mask))) {
+			free_sched_domains(doms, ndoms);
+			kfree(attr);
 			return;
+		}
 	}
 
 	/* Have scheduler rebuild the domains */
-- 
2.43.0