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2023-01-18configfs: fix possible memory leak in configfs_create_dir()Chen Zhongjin
[ Upstream commit c65234b283a65cfbfc94619655e820a5e55199eb ] kmemleak reported memory leaks in configfs_create_dir(): unreferenced object 0xffff888009f6af00 (size 192): comm "modprobe", pid 3777, jiffies 4295537735 (age 233.784s) backtrace: kmem_cache_alloc (mm/slub.c:3250 mm/slub.c:3256 mm/slub.c:3263 mm/slub.c:3273) new_fragment (./include/linux/slab.h:600 fs/configfs/dir.c:163) configfs_register_subsystem (fs/configfs/dir.c:1857) basic_write (drivers/hwtracing/stm/p_basic.c:14) stm_p_basic do_one_initcall (init/main.c:1296) do_init_module (kernel/module/main.c:2455) ... unreferenced object 0xffff888003ba7180 (size 96): comm "modprobe", pid 3777, jiffies 4295537735 (age 233.784s) backtrace: kmem_cache_alloc (mm/slub.c:3250 mm/slub.c:3256 mm/slub.c:3263 mm/slub.c:3273) configfs_new_dirent (./include/linux/slab.h:723 fs/configfs/dir.c:194) configfs_make_dirent (fs/configfs/dir.c:248) configfs_create_dir (fs/configfs/dir.c:296) configfs_attach_group.isra.28 (fs/configfs/dir.c:816 fs/configfs/dir.c:852) configfs_register_subsystem (fs/configfs/dir.c:1881) basic_write (drivers/hwtracing/stm/p_basic.c:14) stm_p_basic do_one_initcall (init/main.c:1296) do_init_module (kernel/module/main.c:2455) ... This is because the refcount is not correct in configfs_make_dirent(). For normal stage, the refcount is changing as: configfs_register_subsystem() configfs_create_dir() configfs_make_dirent() configfs_new_dirent() # set s_count = 1 dentry->d_fsdata = configfs_get(sd); # s_count = 2 ... configfs_unregister_subsystem() configfs_remove_dir() remove_dir() configfs_remove_dirent() # s_count = 1 dput() ... *dentry_unlink_inode()* configfs_d_iput() # s_count = 0, release However, if we failed in configfs_create(): configfs_register_subsystem() configfs_create_dir() configfs_make_dirent() # s_count = 2 ... configfs_create() # fail ->out_remove: configfs_remove_dirent(dentry) configfs_put(sd) # s_count = 1 return PTR_ERR(inode); There is no inode in the error path, so the configfs_d_iput() is lost and makes sd and fragment memory leaked. To fix this, when we failed in configfs_create(), manually call configfs_put(sd) to keep the refcount correct. Fixes: 7063fbf22611 ("[PATCH] configfs: User-driven configuration filesystem") Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-02configfs: fix a race in configfs_{,un}register_subsystem()ChenXiaoSong
[ Upstream commit 84ec758fb2daa236026506868c8796b0500c047d ] When configfs_register_subsystem() or configfs_unregister_subsystem() is executing link_group() or unlink_group(), it is possible that two processes add or delete list concurrently. Some unfortunate interleavings of them can cause kernel panic. One of cases is: A --> B --> C --> D A <-- B <-- C <-- D delete list_head *B | delete list_head *C --------------------------------|----------------------------------- configfs_unregister_subsystem | configfs_unregister_subsystem unlink_group | unlink_group unlink_obj | unlink_obj list_del_init | list_del_init __list_del_entry | __list_del_entry __list_del | __list_del // next == C | next->prev = prev | | next->prev = prev prev->next = next | | // prev == B | prev->next = next Fix this by adding mutex when calling link_group() or unlink_group(), but parent configfs_subsystem is NULL when config_item is root. So I create a mutex configfs_subsystem_mutex. Fixes: 7063fbf22611 ("[PATCH] configfs: User-driven configuration filesystem") Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com> Signed-off-by: Laibin Qiu <qiulaibin@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-01fsnotify: fix fsnotify hooks in pseudo filesystemsAmir Goldstein
commit 29044dae2e746949ad4b9cbdbfb248994d1dcdb4 upstream. Commit 49246466a989 ("fsnotify: move fsnotify_nameremove() hook out of d_delete()") moved the fsnotify delete hook before d_delete() so fsnotify will have access to a positive dentry. This allowed a race where opening the deleted file via cached dentry is now possible after receiving the IN_DELETE event. To fix the regression in pseudo filesystems, convert d_delete() calls to d_drop() (see commit 46c46f8df9aa ("devpts_pty_kill(): don't bother with d_delete()") and move the fsnotify hook after d_drop(). Add a missing fsnotify_unlink() hook in nfsdfs that was found during the audit of fsnotify hooks in pseudo filesystems. Note that the fsnotify hooks in simple_recursive_removal() follow d_invalidate(), so they require no change. Link: https://lore.kernel.org/r/20220120215305.282577-2-amir73il@gmail.com Reported-by: Ivan Delalande <colona@arista.com> Link: https://lore.kernel.org/linux-fsdevel/YeNyzoDM5hP5LtGW@visor/ Fixes: 49246466a989 ("fsnotify: move fsnotify_nameremove() hook out of d_delete()") Cc: stable@vger.kernel.org # v5.3+ Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27configfs: fix config_item refcnt leak in configfs_rmdir()Xiyu Yang
[ Upstream commit 8aebfffacfa379ba400da573a5bf9e49634e38cb ] configfs_rmdir() invokes configfs_get_config_item(), which returns a reference of the specified config_item object to "parent_item" with increased refcnt. When configfs_rmdir() returns, local variable "parent_item" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of configfs_rmdir(). When down_write_killable() fails, the function forgets to decrease the refcnt increased by configfs_get_config_item(), causing a refcnt leak. Fix this issue by calling config_item_put() when down_write_killable() fails. Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-11configfs: calculate the symlink target only onceAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-11configfs: make configfs_create() return inodeAl Viro
Get rid of the callback, deal with that and dentry in callers Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-11configfs: factor dirent removal into helpersChristoph Hellwig
Lots of duplicated code that benefits from a little consolidation. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-04configfs: provide exclusion between IO and removalsAl Viro
Make sure that attribute methods are not called after the item has been removed from the tree. To do so, we * at the point of no return in removals, grab ->frag_sem exclusive and mark the fragment dead. * call the methods of attributes with ->frag_sem taken shared and only after having verified that the fragment is still alive. The main benefit is for method instances - they are guaranteed that the objects they are accessing *and* all ancestors are still there. Another win is that we don't need to bother with extra refcount on config_item when opening a file - the item will be alive for as long as it stays in the tree, and we won't touch it/attributes/any associated data after it's been removed from the tree. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-02configfs: new object reprsenting tree fragmentsAl Viro
Refcounted, hangs of configfs_dirent, created by operations that add fragments to configfs tree (mkdir and configfs_register_{subsystem,group}). Will be used in the next commit to provide exclusion between fragment removal and ->show/->store calls. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-02configfs_register_group() shouldn't be (and isn't) called in rmdirable partsAl Viro
revert cc57c07343bd "configfs: fix registered group removal" It was an attempt to handle something that fundamentally doesn't work - configfs_register_group() should never be done in a part of tree that can be rmdir'ed. And in mainline it never had been, so let's not borrow trouble; the fix was racy anyway, it would take a lot more to make that work and desired semantics is not clear. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-07-10Merge tag 'fsnotify_for_v5.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: "This contains cleanups of the fsnotify name removal hook and also a patch to disable fanotify permission events for 'proc' filesystem" * tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fsnotify: get rid of fsnotify_nameremove() fsnotify: move fsnotify_nameremove() hook out of d_delete() configfs: call fsnotify_rmdir() hook debugfs: call fsnotify_{unlink,rmdir}() hooks debugfs: simplify __debugfs_remove_file() devpts: call fsnotify_unlink() hook tracefs: call fsnotify_{unlink,rmdir}() hooks rpc_pipefs: call fsnotify_{unlink,rmdir}() hooks btrfs: call fsnotify_rmdir() hook fsnotify: add empty fsnotify_{unlink,rmdir}() hooks fanotify: Disallow permission events for proc filesystem
2019-06-20configfs: call fsnotify_rmdir() hookAmir Goldstein
This will allow generating fsnotify delete events on unregister of group/subsystem after the fsnotify_nameremove() hook is removed from d_delete(). The rest of the d_delete() calls from this filesystem are either called recursively from within debugfs_unregister_{group,subsystem}, called from a vfs function that already has delete hooks or are called from shutdown/cleanup code. Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-31Merge tag 'spdx-5.2-rc3-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull yet more SPDX updates from Greg KH: "Here is another set of reviewed patches that adds SPDX tags to different kernel files, based on a set of rules that are being used to parse the comments to try to determine that the license of the file is "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of these matches are included here, a number of "non-obvious" variants of text have been found but those have been postponed for later review and analysis. There is also a patch in here to add the proper SPDX header to a bunch of Kbuild files that we have missed in the past due to new files being added and forgetting that Kbuild uses two different file names for Makefiles. This issue was reported by the Kbuild maintainer. These patches have been out for review on the linux-spdx@vger mailing list, and while they were created by automatic tools, they were hand-verified by a bunch of different people, all whom names are on the patches are reviewers" * tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits) treewide: Add SPDX license identifier - Kbuild treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201 ...
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 145Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 021110 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 84 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190524100844.756442981@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-28configfs: Fix use-after-free when accessing sd->s_dentrySahitya Tummala
In the vfs_statx() context, during path lookup, the dentry gets added to sd->s_dentry via configfs_attach_attr(). In the end, vfs_statx() kills the dentry by calling path_put(), which invokes configfs_d_iput(). Ideally, this dentry must be removed from sd->s_dentry but it doesn't if the sd->s_count >= 3. As a result, sd->s_dentry is holding reference to a stale dentry pointer whose memory is already freed up. This results in use-after-free issue, when this stale sd->s_dentry is accessed later in configfs_readdir() path. This issue can be easily reproduced, by running the LTP test case - sh fs_racer_file_list.sh /config (https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/fs/racer/fs_racer_file_list.sh) Fixes: 76ae281f6307 ('configfs: fix race between dentry put and lookup') Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-05-16Merge tag 'configfs-for-5.2' of git://git.infradead.org/users/hch/configfsLinus Torvalds
Pull configfs update from Christoph Hellwig: - a fix for an error path use after free (YueHaibing) * tag 'configfs-for-5.2' of git://git.infradead.org/users/hch/configfs: configfs: fix possible use-after-free in configfs_register_group
2019-05-08configfs: fix possible use-after-free in configfs_register_groupYueHaibing
In configfs_register_group(), if create_default_group() failed, we forget to unlink the group. It will left a invalid item in the parent list, which may trigger the use-after-free issue seen below: BUG: KASAN: use-after-free in __list_add_valid+0xd4/0xe0 lib/list_debug.c:26 Read of size 8 at addr ffff8881ef61ae20 by task syz-executor.0/5996 CPU: 1 PID: 5996 Comm: syz-executor.0 Tainted: G C 5.0.0+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xa9/0x10e lib/dump_stack.c:113 print_address_description+0x65/0x270 mm/kasan/report.c:187 kasan_report+0x149/0x18d mm/kasan/report.c:317 __list_add_valid+0xd4/0xe0 lib/list_debug.c:26 __list_add include/linux/list.h:60 [inline] list_add_tail include/linux/list.h:93 [inline] link_obj+0xb0/0x190 fs/configfs/dir.c:759 link_group+0x1c/0x130 fs/configfs/dir.c:784 configfs_register_group+0x56/0x1e0 fs/configfs/dir.c:1751 configfs_register_default_group+0x72/0xc0 fs/configfs/dir.c:1834 ? 0xffffffffc1be0000 iio_sw_trigger_init+0x23/0x1000 [industrialio_sw_trigger] do_one_initcall+0xbc/0x47d init/main.c:887 do_init_module+0x1b5/0x547 kernel/module.c:3456 load_module+0x6405/0x8c10 kernel/module.c:3804 __do_sys_finit_module+0x162/0x190 kernel/module.c:3898 do_syscall_64+0x9f/0x450 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x462e99 Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f494ecbcc58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003 RBP: 00007f494ecbcc70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f494ecbd6bc R13: 00000000004bcefa R14: 00000000006f6fb0 R15: 0000000000000004 Allocated by task 5987: set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:497 kmalloc include/linux/slab.h:545 [inline] kzalloc include/linux/slab.h:740 [inline] configfs_register_default_group+0x4c/0xc0 fs/configfs/dir.c:1829 0xffffffffc1bd0023 do_one_initcall+0xbc/0x47d init/main.c:887 do_init_module+0x1b5/0x547 kernel/module.c:3456 load_module+0x6405/0x8c10 kernel/module.c:3804 __do_sys_finit_module+0x162/0x190 kernel/module.c:3898 do_syscall_64+0x9f/0x450 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 5987: set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x130/0x180 mm/kasan/common.c:459 slab_free_hook mm/slub.c:1429 [inline] slab_free_freelist_hook mm/slub.c:1456 [inline] slab_free mm/slub.c:3003 [inline] kfree+0xe1/0x270 mm/slub.c:3955 configfs_register_default_group+0x9a/0xc0 fs/configfs/dir.c:1836 0xffffffffc1bd0023 do_one_initcall+0xbc/0x47d init/main.c:887 do_init_module+0x1b5/0x547 kernel/module.c:3456 load_module+0x6405/0x8c10 kernel/module.c:3804 __do_sys_finit_module+0x162/0x190 kernel/module.c:3898 do_syscall_64+0x9f/0x450 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881ef61ae00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 32 bytes inside of 192-byte region [ffff8881ef61ae00, ffff8881ef61aec0) The buggy address belongs to the page: page:ffffea0007bd8680 count:1 mapcount:0 mapping:ffff8881f6c03000 index:0xffff8881ef61a700 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea0007ca4740 0000000500000005 ffff8881f6c03000 raw: ffff8881ef61a700 000000008010000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881ef61ad00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881ef61ad80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffff8881ef61ae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881ef61ae80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881ef61af00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 5cf6a51e6062 ("configfs: allow dynamic group creation") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-04-08fs: mark expected switch fall-throughsGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warnings: fs/affs/affs.h:124:38: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/configfs/dir.c:1692:11: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/configfs/dir.c:1694:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ceph/file.c:249:3: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/hash.c:233:15: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/hash.c:246:15: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext2/inode.c:1237:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext2/inode.c:1244:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/f2fs/node.c:618:8: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/f2fs/node.c:620:8: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/btrfs/ref-verify.c:522:15: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/gfs2/bmap.c:711:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/gfs2/bmap.c:722:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/jffs2/fs.c:339:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/nfsd/nfs4proc.c:429:12: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ufs/util.h:62:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ufs/util.h:43:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/fcntl.c:770:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/seq_file.c:319:10: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/libfs.c:148:11: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/libfs.c:150:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/signalfd.c:178:7: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/locks.c:1473:16: warning: this statement may fall through [-Wimplicit-fallthrough=] Warning level 3 was used: -Wimplicit-fallthrough=3 This patch is part of the ongoing efforts to enabling -Wimplicit-fallthrough. Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2018-07-17configfs: fix registered group removalMike Christie
This patch fixes a bug where configfs_register_group had added a group in a tree, and userspace has done a rmdir on a dir somewhere above that group and we hit a kernel crash. The problem is configfs_rmdir will detach everything under it and unlink groups on the default_groups list. It will not unlink groups added with configfs_register_group so when configfs_unregister_group is called to drop its references to the group/items we crash when we try to access the freed dentrys. The patch just adds a check for if a rmdir has been done above us and if so just does the unlink part of unregistration. Sorry if you are getting this multiple times. I thouhgt I sent this to some of you and lkml, but I do not see it. Signed-off-by: Mike Christie <mchristi@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-10-19configfs: make ci_type field, some pointers and function arguments constBhumika Goyal
The ci_type field of the config_item structure do not modify the fields of the config_item_type structure it points to. And the other pointers initialized with ci_type do not modify the fields as well. So, make the ci_type field and the pointers initialized with ci_type as const. Make the struct config_item_type *type function argument of functions config_{item/group}_init_type_name const as the argument in both the functions is only stored in the ci_type field of a config_item structure which is now made const. Make the argument of configfs_register_default_group const as it is only passed to the argument of the function config_group_init_type_name which is now const. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-05-09configfs_readdir(): make safe under shared lockAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02configfs_detach_prep(): make sure that wait_mutex won't go awayAl Viro
grab a reference to dentry we'd got the sucker from, and return that dentry via *wait, rather than just returning the address of ->i_mutex. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-19Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: - Preparations of parallel lookups (the remaining main obstacle is the need to move security_d_instantiate(); once that becomes safe, the rest will be a matter of rather short series local to fs/*.c - preadv2/pwritev2 series from Christoph - assorted fixes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (32 commits) splice: handle zero nr_pages in splice_to_pipe() vfs: show_vfsstat: do not ignore errors from show_devname method dcache.c: new helper: __d_add() don't bother with __d_instantiate(dentry, NULL) untangle fsnotify_d_instantiate() a bit uninline d_add() replace d_add_unique() with saner primitive quota: use lookup_one_len_unlocked() cifs_get_root(): use lookup_one_len_unlocked() nfs_lookup: don't bother with d_instantiate(dentry, NULL) kill dentry_unhash() ceph_fill_trace(): don't bother with d_instantiate(dn, NULL) autofs4: don't bother with d_instantiate(dentry, NULL) in ->lookup() configfs: move d_rehash() into configfs_create() for regular files ceph: don't bother with d_rehash() in splice_dentry() namei: teach lookup_slow() to skip revalidate namei: massage lookup_slow() to be usable by lookup_one_len_unlocked() lookup_one_len_unlocked(): use lookup_dcache() namei: simplify invalidation logics in lookup_dcache() namei: change calling conventions for lookup_{fast,slow} and follow_managed() ...
2016-03-14configfs: move d_rehash() into configfs_create() for regular filesAl Viro
... and turn it into d_add in there Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-06configfs: switch ->default groups to a linked listChristoph Hellwig
Replace the current NULL-terminated array of default groups with a linked list. This gets rid of lots of nasty code to size and/or dynamically allocate the array. While we're at it also provide a conveniant helper to remove the default groups. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Felipe Balbi <balbi@kernel.org> [drivers/usb/gadget] Acked-by: Joel Becker <jlbec@evilplan.org> Acked-by: Nicholas Bellinger <nab@linux-iscsi.org> Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
2016-01-22wrappers for ->i_mutex accessAl Viro
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-20Merge branch 'for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending Pull SCSI target updates from Nicholas Bellinger: "The highlights this round include: - Introduce configfs support for unlocked configfs_depend_item() (krzysztof + andrezej) - Conversion of usb-gadget target driver to new function registration interface (andrzej + sebastian) - Enable qla2xxx FC target mode support for Extended Logins (himansu + giridhar) - Enable qla2xxx FC target mode support for Exchange Offload (himansu + giridhar) - Add qla2xxx FC target mode irq affinity notification + selective command queuing. (quinn + himanshu) - Fix iscsi-target deadlock in se_node_acl configfs deletion (sagi + nab) - Convert se_node_acl configfs deletion + se_node_acl->queue_depth to proper se_session->sess_kref + target_get_session() usage. (hch + sagi + nab) - Fix long-standing race between se_node_acl->acl_kref get and get_initiator_node_acl() lookup. (hch + nab) - Fix target/user block-size handling, and make sure netlink reaches all network namespaces (sheng + andy) Note there is an outstanding bug-fix series for remote I_T nexus port TMR LUN_RESET has been posted and still being tested, and will likely become post -rc1 material at this point" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (56 commits) scsi: qla2xxxx: avoid type mismatch in comparison target/user: Make sure netlink would reach all network namespaces target: Obtain se_node_acl->acl_kref during get_initiator_node_acl target: Convert ACL change queue_depth se_session reference usage iscsi-target: Fix potential dead-lock during node acl delete ib_srpt: Convert acl lookup to modern get_initiator_node_acl usage tcm_fc: Convert acl lookup to modern get_initiator_node_acl usage tcm_fc: Wait for command completion before freeing a session target: Fix a memory leak in target_dev_lba_map_store() target: Support aborting tasks with a 64-bit tag usb/gadget: Remove set-but-not-used variables target: Remove an unused variable target: Fix indentation in target_core_configfs.c target/user: Allow user to set block size before enabling device iser-target: Fix non negative ERR_PTR isert_device_get usage target/fcoe: Add tag support to tcm_fc qla2xxx: Check for online flag instead of active reset when transmitting responses qla2xxx: Set all queues to 4k qla2xxx: Disable ZIO at start time. qla2xxx: Move atioq to a different lock to reduce lock contention ...
2016-01-04configfs: implement binary attributesPantelis Antoniou
ConfigFS lacked binary attributes up until now. This patch introduces support for binary attributes in a somewhat similar manner of sysfs binary attributes albeit with changes that fit the configfs usage model. Problems that configfs binary attributes fix are everything that requires a binary blob as part of the configuration of a resource, such as bitstream loading for FPGAs, DTBs for dynamically created devices etc. Look at Documentation/filesystems/configfs/configfs.txt for internals and howto use them. This patch is against linux-next as of today that contains Christoph's configfs rework. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> [hch: folded a fix from Geert Uytterhoeven <geert+renesas@glider.be>] [hch: a few tiny updates based on review feedback] Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-12-20fs: configfs: Add unlocked version of configfs_depend_item()Krzysztof Opasiak
This change is necessary for the SCSI target usb gadget composed with configfs. In this case configfs will be used for two different purposes: to compose a usb gadget and to configure the target part. If an instance of tcm function is created in $CONFIGFS_ROOT/usb_gadget/<gadget>/functions a tpg can be created in $CONFIGFS_ROOT/target/usb_gadget/<wwn>/, but after a tpg is created the tcm function must not be removed until its corresponding tpg is gone. While the configfs_depend/undepend_item() are meant exactly for creating this kind of dependencies, they are not suitable if the other kernel subsystem happens to be another subsystem in configfs, so this patch adds unlocked versions meant for configfs callbacks. Above description has been provided by: Andrzej Pietrasiewicz <andrzej.p@samsung.com> In configfs_depend_item() we have to consider two possible cases: 1) When we are called to depend another item in the same subsystem as caller In this case we should skip locking configfs root as we know that configfs is in valid state and our subsystem will not be unregistered during this call. 2) When we are called to depend item in different subsystem than our caller In this case we are also sure that configfs is in valid state but we have to lock root of configfs to avoid unregistration of target's subsystem. As it is other than caller's subsystem, there may be nothing what protects us against unregistration of that subsystem. Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-12-20fs: configfs: Factor out configfs_find_subsys_dentry()Krzysztof Opasiak
configfs_depend_item() is quite complicated and should be split up into smaller functions. This also allow to share this code with other functions. Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-12-20fs: configfs: Factor out configfs_do_depend_item()Krzysztof Opasiak
configfs_depend_item() is quite complicated and should be split up into smaller functions. This also allow to share this code with other functions. Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-12-20fs: configfs: Drop unused parameter from configfs_undepend_item()Krzysztof Opasiak
subsys parameter is never used by configfs_undepend_item() so there is no point in passing it to this function. Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-11-20configfs: allow dynamic group creationDaniel Baluta
This patchset introduces IIO software triggers, offers a way of configuring them via configfs and adds the IIO hrtimer based interrupt source to be used with software triggers. The architecture is now split in 3 parts, to remove all IIO trigger specific parts from IIO configfs core: (1) IIO configfs - creates the root of the IIO configfs subsys. (2) IIO software triggers - software trigger implementation, dynamically creating /config/iio/triggers group. (3) IIO hrtimer trigger - is the first interrupt source for software triggers (with syfs to follow). Each trigger type can implement its own set of attributes. Lockdep seems to be happy with the locking in configfs patch. This patch (of 5): We don't want to hardcode default groups at subsystem creation time. We export: * configfs_register_group * configfs_unregister_group to allow drivers to programatically create/destroy groups later, after module init time. This is needed for IIO configfs support. (akpm: the other 4 patches to be merged via the IIO tree) Signed-off-by: Daniel Baluta <daniel.baluta@intel.com> Suggested-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Joel Becker <jlbec@evilplan.org> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Octavian Purdila <octavian.purdila@intel.com> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: Adriana Reus <adriana.reus@intel.com> Cc: Cristina Opriceana <cristina.opriceana@gmail.com> Cc: Peter Meerwald <pmeerw@pmeerw.net> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inodeDavid Howells
Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17configfs: fold create_dir() into its only callerAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17configfs: configfs_create() init callback is never NULL and it never failsAl Viro
... so make it return void and drop the check for it being non-NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19assorted conversions to %p[dD]Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-06-04fs/configfs: use pr_fmtFabian Frederick
Add pr_fmt based on module name. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04fs/configfs: convert printk to pr_foo()Fabian Frederick
Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-21configfs: fix race between dentry put and lookupJunxiao Bi
A race window in configfs, it starts from one dentry is UNHASHED and end before configfs_d_iput is called. In this window, if a lookup happen, since the original dentry was UNHASHED, so a new dentry will be allocated, and then in configfs_attach_attr(), sd->s_dentry will be updated to the new dentry. Then in configfs_d_iput(), BUG_ON(sd->s_dentry != dentry) will be triggered and system panic. sys_open: sys_close: ... fput dput dentry_kill __d_drop <--- dentry unhashed here, but sd->dentry still point to this dentry. lookup_real configfs_lookup configfs_attach_attr---> update sd->s_dentry to new allocated dentry here. d_kill configfs_d_iput <--- BUG_ON(sd->s_dentry != dentry) triggered here. To fix it, change configfs_d_iput to not update sd->s_dentry if sd->s_count > 2, that means there are another dentry is using the sd beside the one that is going to be put. Use configfs_dirent_lock in configfs_attach_attr to sync with configfs_d_iput. With the following steps, you can reproduce the bug. 1. enable ocfs2, this will mount configfs at /sys/kernel/config and fill configure in it. 2. run the following script. while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done & while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done & Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15consolidate simple ->d_delete() instancesAl Viro
Rename simple_delete_dentry() to always_delete_dentry() and export it. Export simple_dentry_operations, while we are at it, and get rid of their duplicates Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-14Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs stuff from Al Viro: "O_TMPFILE ABI changes, Oleg's fput() series, misc cleanups, including making simple_lookup() usable for filesystems with non-NULL s_d_op, which allows us to get rid of quite a bit of ugliness" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: sunrpc: now we can just set ->s_d_op cgroup: we can use simple_lookup() now efivarfs: we can use simple_lookup() now make simple_lookup() usable for filesystems that set ->s_d_op configfs: don't open-code d_alloc_name() __rpc_lookup_create_exclusive: pass string instead of qstr rpc_create_*_dir: don't bother with qstr llist: llist_add() can use llist_add_batch() llist: fix/simplify llist_add() and llist_add_batch() fput: turn "list_head delayed_fput_list" into llist_head fs/file_table.c:fput(): add comment Safer ABI for O_TMPFILE
2013-07-14configfs: don't open-code d_alloc_name()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull third set of VFS updates from Al Viro: "Misc stuff all over the place. There will be one more pile in a couple of days" This is an "evil merge" that also uses the new d_count helper in fs/configfs/dir.c, missed by commit 84d08fa888e7 ("helper for reading ->d_count") * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ncpfs: fix error return code in ncp_parse_options() locks: move file_lock_list to a set of percpu hlist_heads and convert file_lock_lock to an lglock seq_file: add seq_list_*_percpu helpers f2fs: fix readdir incorrectness mode_t whack-a-mole... lustre: kill the pointless wrapper helper for reading ->d_count
2013-06-29[readdir] convert configfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-21configfs: move the dereference below the NULL testWei Yongjun
The dereference should be moved below the NULL test. spatch with a semantic match is used to found this. (http://coccinelle.lip6.fr/) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17lseek: the "whence" argument is called "whence"Andrew Morton
But the kernel decided to call it "origin" instead. Fix most of the sites. Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>