kernel/linux.git/fs/nilfs2/sysfs.c, branch v6.6.131

nilfs2: fix CFI failure when accessing /sys/fs/nilfs2/features/*

2025-09-25T09:00:07+00:00

commit 025e87f8ea2ae3a28bf1fe2b052bfa412c27ed4a upstream. When accessing one of the files under /sys/fs/nilfs2/features when CONFIG_CFI_CLANG is enabled, there is a CFI violation: CFI failure at kobj_attr_show+0x59/0x80 (target: nilfs_feature_revision_show+0x0/0x30; expected type: 0xfc392c4d) ... Call Trace: sysfs_kf_seq_show+0x2a6/0x390 ? __cfi_kobj_attr_show+0x10/0x10 kernfs_seq_show+0x104/0x15b seq_read_iter+0x580/0xe2b ... When the kobject of the kset for /sys/fs/nilfs2 is initialized, its ktype is set to kset_ktype, which has a ->sysfs_ops of kobj_sysfs_ops. When nilfs_feature_attr_group is added to that kobject via sysfs_create_group(), the kernfs_ops of each files is sysfs_file_kfops_rw, which will call sysfs_kf_seq_show() when ->seq_show() is called. sysfs_kf_seq_show() in turn calls kobj_attr_show() through ->sysfs_ops->show(). kobj_attr_show() casts the provided attribute out to a 'struct kobj_attribute' via container_of() and calls ->show(), resulting in the CFI violation since neither nilfs_feature_revision_show() nor nilfs_feature_README_show() match the prototype of ->show() in 'struct kobj_attribute'. Resolve the CFI violation by adjusting the second parameter in nilfs_feature_{revision,README}_show() from 'struct attribute' to 'struct kobj_attribute' to match the expected prototype. Link: https://lkml.kernel.org/r/20250906144410.22511-1-konishi.ryusuke@gmail.com Fixes: aebe17f68444 ("nilfs2: add /sys/fs/nilfs2/features group") Signed-off-by: Nathan Chancellor Signed-off-by: Ryusuke Konishi Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202509021646.bc78d9ef-lkp@intel.com/ Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

nilfs2: protect references to superblock parameters exposed in sysfs

2024-09-12T09:11:28+00:00

commit 683408258917541bdb294cd717c210a04381931e upstream. The superblock buffers of nilfs2 can not only be overwritten at runtime for modifications/repairs, but they are also regularly swapped, replaced during resizing, and even abandoned when degrading to one side due to backing device issues. So, accessing them requires mutual exclusion using the reader/writer semaphore "nilfs->ns_sem". Some sysfs attribute show methods read this superblock buffer without the necessary mutual exclusion, which can cause problems with pointer dereferencing and memory access, so fix it. Link: https://lkml.kernel.org/r/20240811100320.9913-1-konishi.ryusuke@gmail.com Fixes: da7141fb78db ("nilfs2: add /sys/fs/nilfs2/ group") Signed-off-by: Ryusuke Konishi Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

nilfs2: use default_groups in kobj_type

2021-12-29T09:53:48+00:00

There are currently 2 ways to create a set of sysfs files for a kobj_type, through the default_attrs field, and the default_groups field. Move the nilfs2 code to use default_groups field which has been the preferred way since aa30f47cf666 ("kobject: Add support for default attribute groups to kobj_type") so that we can soon get rid of the obsolete default_attrs field. Acked-by: Ryusuke Konishi Link: https://lore.kernel.org/r/20211228144252.390554-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

nilfs2: remove filenames from file comments

2021-11-09T18:02:52+00:00

Remove filenames that are not particularly useful in file comments, and suppress checkpatch warnings WARNING: It's generally not useful to have the filename in the file Link: https://lkml.kernel.org/r/1635151862-11547-3-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi Cc: Qing Wang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: replace snprintf in show functions with sysfs_emit

2021-11-09T18:02:51+00:00

Patch series "nilfs2 updates". This patch (of 2): coccicheck complains about the use of snprintf() in sysfs show functions. Fix the coccicheck warning: WARNING: use scnprintf or sprintf. Use sysfs_emit instead of scnprintf or sprintf makes more sense. Link: https://lkml.kernel.org/r/1635151862-11547-1-git-send-email-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/1634095759-4625-1-git-send-email-wangqing@vivo.com Link: https://lkml.kernel.org/r/1635151862-11547-2-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Qing Wang Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group

2021-09-08T18:50:27+00:00

kobject_put() should be used to cleanup the memory associated with the kobject instead of kobject_del(). See the section "Kobject removal" of "Documentation/core-api/kobject.rst". Link: https://lkml.kernel.org/r/20210629022556.3985106-7-sunnanyong@huawei.com Link: https://lkml.kernel.org/r/1625651306-10829-7-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Nanyong Sun Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group

2021-09-08T18:50:27+00:00

If kobject_init_and_add returns with error, kobject_put() is needed here to avoid memory leak, because kobject_init_and_add may return error without freeing the memory associated with the kobject it allocated. Link: https://lkml.kernel.org/r/20210629022556.3985106-6-sunnanyong@huawei.com Link: https://lkml.kernel.org/r/1625651306-10829-6-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Nanyong Sun Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group

2021-09-08T18:50:27+00:00

The kobject_put() should be used to cleanup the memory associated with the kobject instead of kobject_del. See the section "Kobject removal" of "Documentation/core-api/kobject.rst". Link: https://lkml.kernel.org/r/20210629022556.3985106-5-sunnanyong@huawei.com Link: https://lkml.kernel.org/r/1625651306-10829-5-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Nanyong Sun Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group

2021-09-08T18:50:27+00:00

If kobject_init_and_add return with error, kobject_put() is needed here to avoid memory leak, because kobject_init_and_add may return error without freeing the memory associated with the kobject it allocated. Link: https://lkml.kernel.org/r/20210629022556.3985106-4-sunnanyong@huawei.com Link: https://lkml.kernel.org/r/1625651306-10829-4-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Nanyong Sun Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: fix NULL pointer in nilfs_##name##_attr_release

2021-09-08T18:50:27+00:00

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 Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds