| From 2d8e2ebfab78cf8454e1ee49224e813d3ee3adfd Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Tue, 7 Sep 2021 20:00:12 -0700 |
| Subject: nilfs2: fix NULL pointer in nilfs_##name##_attr_release |
| |
| From: Nanyong Sun <sunnanyong@huawei.com> |
| |
| [ Upstream commit dbc6e7d44a514f231a64d9d5676e001b660b6448 ] |
| |
| In nilfs_##name##_attr_release, kobj->parent should not be referenced |
| because it is a NULL pointer. The release() method of kobject is always |
| called in kobject_put(kobj), in the implementation of kobject_put(), the |
| kobj->parent will be assigned as NULL before call the release() method. |
| So just use kobj to get the subgroups, which is more efficient and can fix |
| a NULL pointer reference problem. |
| |
| Link: https://lkml.kernel.org/r/20210629022556.3985106-3-sunnanyong@huawei.com |
| Link: https://lkml.kernel.org/r/1625651306-10829-3-git-send-email-konishi.ryusuke@gmail.com |
| Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> |
| Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| fs/nilfs2/sysfs.c | 8 +++----- |
| 1 file changed, 3 insertions(+), 5 deletions(-) |
| |
| diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c |
| index d2d8ea89937a..ec85ac53720d 100644 |
| --- a/fs/nilfs2/sysfs.c |
| +++ b/fs/nilfs2/sysfs.c |
| @@ -51,11 +51,9 @@ static const struct sysfs_ops nilfs_##name##_attr_ops = { \ |
| #define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \ |
| static void nilfs_##name##_attr_release(struct kobject *kobj) \ |
| { \ |
| - struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \ |
| - struct the_nilfs *nilfs = container_of(kobj->parent, \ |
| - struct the_nilfs, \ |
| - ns_##parent_name##_kobj); \ |
| - subgroups = nilfs->ns_##parent_name##_subgroups; \ |
| + struct nilfs_sysfs_##parent_name##_subgroups *subgroups = container_of(kobj, \ |
| + struct nilfs_sysfs_##parent_name##_subgroups, \ |
| + sg_##name##_kobj); \ |
| complete(&subgroups->sg_##name##_kobj_unregister); \ |
| } \ |
| static struct kobj_type nilfs_##name##_ktype = { \ |
| -- |
| 2.33.0 |
| |