mm/damon/sysfs: cleanup attrs subdirs on context dir setup failure

commit 9814cc832b88bd040fc2a1817c2b5469d0f7e862 upstream.

When a context DAMON sysfs directory setup is failed after setup of attrs/
directory, subdirectories of attrs/ directory are not cleaned up.  As a
result, DAMON sysfs interface is nearly broken until the system reboots,
and the memory for the unremoved directory is leaked.

Cleanup the directories under such failures.

Link: https://lkml.kernel.org/r/20251225023043.18579-3-sj@kernel.org
Fixes: c951cd3b8901 ("mm/damon: implement a minimal stub for sysfs-based DAMON interface")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: chongjiapeng <jiapeng.chong@linux.alibaba.com>
Cc: <stable@vger.kernel.org> # 5.18.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 2b4920a722e495c9e3f2ace8eaeae2aac9deb664..2caeca5624ce8a0a042958fdfb86c11d550823c9 100644 (file)
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -922,7 +922,7 @@ static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context)
 
        err = damon_sysfs_context_set_targets(context);
        if (err)
-               goto put_attrs_out;
+               goto rmdir_put_attrs_out;
 
        err = damon_sysfs_context_set_schemes(context);
        if (err)
@@ -932,7 +932,8 @@ static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context)
 put_targets_attrs_out:
        kobject_put(&context->targets->kobj);
        context->targets = NULL;
-put_attrs_out:
+rmdir_put_attrs_out:
+       damon_sysfs_attrs_rm_dirs(context->attrs);
        kobject_put(&context->attrs->kobj);
        context->attrs = NULL;
        return err;