kernel/git/stable/linux.git/fs/nilfs2/sysfs.c, branch linux-5.10.y

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

2025-10-02T11:35:41+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

2024-09-12T09:06:51+00:00

[ Upstream commit 683408258917541bdb294cd717c210a04381931e ] 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: Sasha Levin

nilfs2: replace snprintf in show functions with sysfs_emit

2024-09-12T09:06:50+00:00

[ Upstream commit 3bcd6c5bd483287f4a09d3d59a012d47677b6edc ] 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 Stable-dep-of: 683408258917 ("nilfs2: protect references to superblock parameters exposed in sysfs") Signed-off-by: Sasha Levin

nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group

2021-09-26T12:09:01+00:00

[ Upstream commit 17243e1c3072b8417a5ebfc53065d0a87af7ca77 ] 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 Signed-off-by: Sasha Levin

nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group

2021-09-26T12:09:01+00:00

[ Upstream commit b2fe39c248f3fa4bbb2a20759b4fdd83504190f7 ] 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 Signed-off-by: Sasha Levin

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

2021-09-26T12:09:01+00:00

[ Upstream commit a3e181259ddd61fd378390977a1e4e2316853afa ] 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 Signed-off-by: Sasha Levin

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

2021-09-26T12:09:01+00:00

[ Upstream commit 24f8cb1ed057c840728167dab33b32e44147c86f ] 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 Signed-off-by: Sasha Levin

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

2021-09-26T12:09:00+00:00

[ 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 Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

nilfs2: fix memory leak in nilfs_sysfs_create_device_group

2021-09-26T12:09:00+00:00

[ Upstream commit 5f5dec07aca7067216ed4c1342e464e7307a9197 ] Patch series "nilfs2: fix incorrect usage of kobject". This patchset from Nanyong Sun fixes memory leak issues and a NULL pointer dereference issue caused by incorrect usage of kboject in nilfs2 sysfs implementation. This patch (of 6): Reported by syzkaller: BUG: memory leak unreferenced object 0xffff888100ca8988 (size 8): comm "syz-executor.1", pid 1930, jiffies 4294745569 (age 18.052s) hex dump (first 8 bytes): 6c 6f 6f 70 31 00 ff ff loop1... backtrace: kstrdup+0x36/0x70 mm/util.c:60 kstrdup_const+0x35/0x60 mm/util.c:83 kvasprintf_const+0xf1/0x180 lib/kasprintf.c:48 kobject_set_name_vargs+0x56/0x150 lib/kobject.c:289 kobject_add_varg lib/kobject.c:384 [inline] kobject_init_and_add+0xc9/0x150 lib/kobject.c:473 nilfs_sysfs_create_device_group+0x150/0x7d0 fs/nilfs2/sysfs.c:986 init_nilfs+0xa21/0xea0 fs/nilfs2/the_nilfs.c:637 nilfs_fill_super fs/nilfs2/super.c:1046 [inline] nilfs_mount+0x7b4/0xe80 fs/nilfs2/super.c:1316 legacy_get_tree+0x105/0x210 fs/fs_context.c:592 vfs_get_tree+0x8e/0x2d0 fs/super.c:1498 do_new_mount fs/namespace.c:2905 [inline] path_mount+0xf9b/0x1990 fs/namespace.c:3235 do_mount+0xea/0x100 fs/namespace.c:3248 __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount fs/namespace.c:3433 [inline] __x64_sys_mount+0x14b/0x1f0 fs/namespace.c:3433 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae If kobject_init_and_add return with error, then the cleanup of kobject is needed because memory may be allocated in kobject_init_and_add without freeing. And the place of cleanup_dev_kobject should use kobject_put to free the memory associated with the kobject. As the section "Kobject removal" of "Documentation/core-api/kobject.rst" says, kobject_del() just makes the kobject "invisible", but it is not cleaned up. And no more cleanup will do after cleanup_dev_kobject, so kobject_put is needed here. Link: https://lkml.kernel.org/r/1625651306-10829-1-git-send-email-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/1625651306-10829-2-git-send-email-konishi.ryusuke@gmail.com Reported-by: Hulk Robot Link: https://lkml.kernel.org/r/20210629022556.3985106-2-sunnanyong@huawei.com Signed-off-by: Nanyong Sun Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

nilfs2: fix memory leak in nilfs_sysfs_delete_device_group

2021-06-30T12:47:24+00:00

[ Upstream commit 8fd0c1b0647a6bda4067ee0cd61e8395954b6f28 ] My local syzbot instance hit memory leak in nilfs2. The problem was in missing kobject_put() in nilfs_sysfs_delete_device_group(). kobject_del() does not call kobject_cleanup() for passed kobject and it leads to leaking duped kobject name if kobject_put() was not called. Fail log: BUG: memory leak unreferenced object 0xffff8880596171e0 (size 8): comm "syz-executor379", pid 8381, jiffies 4294980258 (age 21.100s) hex dump (first 8 bytes): 6c 6f 6f 70 30 00 00 00 loop0... backtrace: kstrdup+0x36/0x70 mm/util.c:60 kstrdup_const+0x53/0x80 mm/util.c:83 kvasprintf_const+0x108/0x190 lib/kasprintf.c:48 kobject_set_name_vargs+0x56/0x150 lib/kobject.c:289 kobject_add_varg lib/kobject.c:384 [inline] kobject_init_and_add+0xc9/0x160 lib/kobject.c:473 nilfs_sysfs_create_device_group+0x150/0x800 fs/nilfs2/sysfs.c:999 init_nilfs+0xe26/0x12b0 fs/nilfs2/the_nilfs.c:637 Link: https://lkml.kernel.org/r/20210612140559.20022-1-paskripkin@gmail.com Fixes: da7141fb78db ("nilfs2: add /sys/fs/nilfs2/ group") Signed-off-by: Pavel Skripkin Acked-by: Ryusuke Konishi Cc: Michael L. Semon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin