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364595a6 |
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30-Mar-2023 |
Jeff Layton <jlayton@kernel.org> |
fs: consolidate duplicate dt_type helpers There are three copies of the same dt_type helper sprinkled around the tree. Convert them to use the common fs_umode_to_dtype function instead, which has the added advantage of properly returning DT_UNKNOWN when given a mode that contains an unrecognized type. Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Phillip Potter <phil@philpotter.co.uk> Suggested-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Jeff Layton <jlayton@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Christian Brauner <brauner@kernel.org> Message-Id: <20230330104144.75547-1-jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
c54bd91e |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port ->mkdir() to pass mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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c65234b2 |
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16-Oct-2022 |
Chen Zhongjin <chenzhongjin@huawei.com> |
configfs: fix possible memory leak in configfs_create_dir() 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>
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#
84ec758f |
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15-Feb-2022 |
ChenXiaoSong <chenxiaosong2@huawei.com> |
configfs: fix a race in configfs_{,un}register_subsystem() 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>
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#
29044dae |
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20-Jan-2022 |
Amir Goldstein <amir73il@gmail.com> |
fsnotify: fix fsnotify hooks in pseudo filesystems 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>
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#
c42dd069 |
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24-Aug-2021 |
Sishuai Gong <sishuai@purdue.edu> |
configfs: fix a race in configfs_lookup() When configfs_lookup() is executing list_for_each_entry(), it is possible that configfs_dir_lseek() is calling list_del(). Some unfortunate interleavings of them can cause a kernel NULL pointer dereference error Thread 1 Thread 2 //configfs_dir_lseek() //configfs_lookup() list_del(&cursor->s_sibling); list_for_each_entry(sd, ...) Fix this by grabbing configfs_dirent_lock in configfs_lookup() while iterating ->s_children. Signed-off-by: Sishuai Gong <sishuai@purdue.edu> Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
d07f132a |
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24-Aug-2021 |
Christoph Hellwig <hch@lst.de> |
configfs: fold configfs_attach_attr into configfs_lookup This makes it more clear what gets added to the dcache and prepares for an additional locking fix. Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
899587c8 |
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24-Aug-2021 |
Christoph Hellwig <hch@lst.de> |
configfs: simplify the configfs_dirent_is_ready Return the error directly instead of using a goto. Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
417b962d |
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24-Aug-2021 |
Christoph Hellwig <hch@lst.de> |
configfs: return -ENAMETOOLONG earlier in configfs_lookup Just like most other file systems: get the simple checks out of the way first. Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
fa60ce2c |
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06-May-2021 |
Masahiro Yamada <masahiroy@kernel.org> |
treewide: remove editor modelines and cruft The section "19) Editor modelines and other cruft" in Documentation/process/coding-style.rst clearly says, "Do not include any of these in source files." I recently receive a patch to explicitly add a new one. Let's do treewide cleanups, otherwise some people follow the existing code and attempt to upstream their favoriate editor setups. It is even nicer if scripts/checkpatch.pl can check it. If we like to impose coding style in an editor-independent manner, I think editorconfig (patch [1]) is a saner solution. [1] https://lore.kernel.org/lkml/20200703073143.423557-1-danny@kdrag0n.dev/ Link: https://lkml.kernel.org/r/20210324054457.1477489-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> [auxdisplay] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
549c7297 |
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21-Jan-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
fs: make helpers idmap mount aware Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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#
65cdb4a2 |
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13-Nov-2020 |
Alex Shi <alex.shi@linux.alibaba.com> |
configfs: fix kernel-doc markup issue Add explanation for 'frag' parameter to avoid kernel-doc issue: fs/configfs/dir.c:277: warning: Function parameter or member 'frag' not described in 'configfs_create_dir' Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
ce9bebe6 |
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15-Oct-2020 |
Randy Dunlap <rdunlap@infradead.org> |
fs: configfs: delete repeated words in comments Drop duplicated words {the, that} in comments. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Joel Becker <jlbec@evilplan.org> Cc: Christoph Hellwig <hch@lst.de> Link: https://lkml.kernel.org/r/20200811021826.25032-1-rdunlap@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
df561f66 |
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23-Aug-2020 |
Gustavo A. R. Silva <gustavoars@kernel.org> |
treewide: Use fallthrough pseudo-keyword Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
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#
8aebfffa |
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25-Apr-2020 |
Xiyu Yang <xiyuyang19@fudan.edu.cn> |
configfs: fix config_item refcnt leak in configfs_rmdir() 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>
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#
e9c03af2 |
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11-Sep-2019 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: calculate the symlink target only once Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
2743c515 |
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11-Sep-2019 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: make configfs_create() return inode 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>
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#
1cf7a003 |
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11-Sep-2019 |
Christoph Hellwig <hch@lst.de> |
configfs: factor dirent removal into helpers Lots of duplicated code that benefits from a little consolidation. Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
b0841eef |
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31-Aug-2019 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: provide exclusion between IO and removals 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>
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#
47320fbe |
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25-Aug-2019 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: new object reprsenting tree fragments 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>
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#
f19e4ed1 |
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29-Aug-2019 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs_register_group() shouldn't be (and isn't) called in rmdirable parts 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>
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#
6146e78c |
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26-May-2019 |
Amir Goldstein <amir73il@gmail.com> |
configfs: call fsnotify_rmdir() hook 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>
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#
328970de |
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23-May-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 145 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>
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#
f6122ed2 |
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03-Jan-2019 |
Sahitya Tummala <stummala@codeaurora.org> |
configfs: Fix use-after-free when accessing sd->s_dentry 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>
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#
35399f87 |
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04-May-2019 |
YueHaibing <yuehaibing@huawei.com> |
configfs: fix possible use-after-free in configfs_register_group 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>
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#
0a4c9265 |
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23-Jan-2019 |
Gustavo A. R. Silva <gustavo@embeddedor.com> |
fs: mark expected switch fall-throughs 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>
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#
cc57c073 |
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15-Jul-2018 |
Mike Christie <mchristi@redhat.com> |
configfs: fix registered group removal 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>
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#
aa293583 |
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16-Oct-2017 |
Bhumika Goyal <bhumirks@gmail.com> |
configfs: make ci_type field, some pointers and function arguments const 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>
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#
a01b3007 |
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20-Apr-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs_readdir(): make safe under shared lock Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
48f35b7b |
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11-Apr-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs_detach_prep(): make sure that wait_mutex won't go away 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>
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#
5cf3b560 |
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07-Mar-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: move d_rehash() into configfs_create() for regular files ... and turn it into d_add in there Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
1ae1602d |
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26-Feb-2016 |
Christoph Hellwig <hch@lst.de> |
configfs: switch ->default groups to a linked list 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>
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#
5955102c |
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22-Jan-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
wrappers for ->i_mutex access 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>
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#
03607ace |
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22-Oct-2015 |
Pantelis Antoniou <pantelis.antoniou@konsulko.com> |
configfs: implement binary attributes 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>
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#
d79d75b5 |
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11-Dec-2015 |
Krzysztof Opasiak <k.opasiak@samsung.com> |
fs: configfs: Add unlocked version of configfs_depend_item() 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>
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#
9a70adff |
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11-Dec-2015 |
Krzysztof Opasiak <k.opasiak@samsung.com> |
fs: configfs: Factor out configfs_find_subsys_dentry() 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>
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#
9fb434e7 |
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11-Dec-2015 |
Krzysztof Opasiak <k.opasiak@samsung.com> |
fs: configfs: Factor out configfs_do_depend_item() 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>
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#
9a9e3415 |
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11-Dec-2015 |
Krzysztof Opasiak <k.opasiak@samsung.com> |
fs: configfs: Drop unused parameter from configfs_undepend_item() 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>
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#
5cf6a51e |
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20-Nov-2015 |
Daniel Baluta <daniel.baluta@intel.com> |
configfs: allow dynamic group creation 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>
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#
2b0143b5 |
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17-Mar-2015 |
David Howells <dhowells@redhat.com> |
VFS: normal filesystems (and lustre): d_inode() annotations 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>
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#
6683de38 |
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02-Mar-2015 |
David Howells <dhowells@redhat.com> |
configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode 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>
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#
1cf97d0d |
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28-Jan-2015 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: fold create_dir() into its only caller Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
c88b1e70 |
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28-Jan-2015 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: configfs_create() init callback is never NULL and it never fails ... so make it return void and drop the check for it being non-NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
a455589f |
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21-Oct-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
assorted conversions to %p[dD] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
1d88aa44 |
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04-Jun-2014 |
Fabian Frederick <fabf@skynet.be> |
fs/configfs: use pr_fmt 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>
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#
c6686931 |
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04-Jun-2014 |
Fabian Frederick <fabf@skynet.be> |
fs/configfs: convert printk to pr_foo() 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>
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#
76ae281f |
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21-Nov-2013 |
Junxiao Bi <junxiao.bi@oracle.com> |
configfs: fix race between dentry put and lookup 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>
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#
b26d4cd3 |
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25-Oct-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
consolidate simple ->d_delete() instances 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>
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#
ec193cf5 |
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14-Jul-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: don't open-code d_alloc_name() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
52018855 |
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15-May-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
[readdir] convert configfs Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
496ad9aa |
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23-Jan-2013 |
Al Viro <viro@zeniv.linux.org.uk> |
new helper: file_inode(file) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
49deb4bc |
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21-Feb-2013 |
Wei Yongjun <yongjun_wei@trendmicro.com.cn> |
configfs: move the dereference below the NULL test 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>
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#
965c8e59 |
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17-Dec-2012 |
Andrew Morton <akpm@linux-foundation.org> |
lseek: the "whence" argument is called "whence" 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>
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#
00cd8dd3 |
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10-Jun-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
stop passing nameidata to ->lookup() Just the flags; only NFS cares even about that, but there are legitimate uses for such argument. And getting rid of that completely would require splitting ->lookup() into a couple of methods (at least), so let's leave that alone for now... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
2a152ad3 |
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17-Mar-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
make configfs_pin_fs() return root dentry on success ... and make configfs_mnt static Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
0dd6c08a |
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17-Mar-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: configfs_create_dir() has parent dentry in dentry->d_parent no need to play sick games with parent item, internal mount, etc. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
b7c177fc |
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17-Mar-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: kill configfs_sb Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
81d44ed1 |
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17-Mar-2012 |
Al Viro <viro@zeniv.linux.org.uk> |
configfs: don't bother with checks for mkdir/rmdir/unlink/symlink in root just give root directory separate inode_operations without all those methods... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
18bb1db3 |
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25-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
switch vfs_mkdir() and ->mkdir() to umode_t vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
c972b4bc |
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08-Dec-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
vfs: live vfsmounts never have NULL ->mnt_sb Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
4c1d5a64 |
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07-Dec-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
vfs: for usbfs, etc. internal vfsmounts ->mnt_sb->s_root == ->mnt_root Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
98702467 |
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27-May-2011 |
Sage Weil <sage@newdream.net> |
configfs: remove unnecessary dentry_unhash on rmdir, dir rename configfs does not have problems with references to unlinked directories. CC: Joel Becker <jlbec@evilplan.org> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
79bf7c73 |
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24-May-2011 |
Sage Weil <sage@newdream.net> |
vfs: push dentry_unhash on rmdir into file systems Only a few file systems need this. Start by pushing it down into each fs rmdir method (except gfs2 and xfs) so it can be dealt with on a per-fs basis. This does not change behavior for any in-tree file systems. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
24307aa1 |
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18-May-2011 |
Joel Becker <jlbec@evilplan.org> |
configfs: Fix race between configfs_readdir() and configfs_d_iput() configfs_readdir() will use the existing inode numbers of inodes in the dcache, but it makes them up for attribute files that aren't currently instantiated. There is a race where a closing attribute file can be tearing down at the same time as configfs_readdir() is trying to get its inode number. We want to get the inode number of open attribute files, because they should match while instantiated. We can't lock down the transition where dentry->d_inode is set to NULL, so we just check for NULL there. We can, however, ensure that an inode we find isn't iput() in configfs_d_iput() until after we've accessed it. Signed-off-by: Joel Becker <jlbec@evilplan.org>
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#
df7f9967 |
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22-Feb-2011 |
Joel Becker <jlbec@evilplan.org> |
configfs: Don't try to d_delete() negative dentries. When configfs is faking mkdir() on its subsystem or default group objects, it starts by adding a negative dentry. It then tries to instantiate the group. If that should fail, it must clean up after itself. I was using d_delete() here, but configfs_attach_group() promises to return an empty dentry on error. d_delete() explodes with the entry dentry. Let's try d_drop() instead. The unhashing is what we want for our dentry. Signed-off-by: Joel Becker <jlbec@evilplan.org>
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#
25985edc |
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30-Mar-2011 |
Lucas De Marchi <lucas.demarchi@profusion.mobi> |
Fix common misspellings Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
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#
d463a0c4 |
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12-Jan-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
switch configfs Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
fb045adb |
|
06-Jan-2011 |
Nick Piggin <npiggin@kernel.dk> |
fs: dcache reduce branches in lookup path Reduce some branches and memory accesses in dcache lookup by adding dentry flags to indicate common d_ops are set, rather than having to check them. This saves a pointer memory access (dentry->d_op) in common path lookup situations, and saves another pointer load and branch in cases where we have d_op but not the particular operation. Patched with: git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i Signed-off-by: Nick Piggin <npiggin@kernel.dk>
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#
b7ab39f6 |
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06-Jan-2011 |
Nick Piggin <npiggin@kernel.dk> |
fs: dcache scale dentry refcount Make d_count non-atomic and protect it with d_lock. This allows us to ensure a 0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when we start protecting many other dentry members with d_lock. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
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#
fe15ce44 |
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06-Jan-2011 |
Nick Piggin <npiggin@kernel.dk> |
fs: change d_delete semantics Change d_delete from a dentry deletion notification to a dentry caching advise, more like ->drop_inode. Require it to be constant and idempotent, and not take d_lock. This is how all existing filesystems use the callback anyway. This makes fine grained dentry locking of dput and dentry lru scanning much simpler. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
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fbc8d4c0 |
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06-Jan-2011 |
Nick Piggin <npiggin@kernel.dk> |
config fs: avoid switching ->d_op on live dentry Switching d_op on a live dentry is racy in general, so avoid it. In this case it is a negative dentry, which is safer, but there are still concurrent ops which may be called on d_op in that case (eg. d_revalidate). So in general a filesystem may not do this. Fix configfs so as not to do this. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
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d83c49f3 |
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30-Apr-2010 |
Al Viro <viro@zeniv.linux.org.uk> |
Fix the regression created by "set S_DEAD on unlink()..." commit 1) i_flags simply doesn't work for mount/unlink race prevention; we may have many links to file and rm on one of those obviously shouldn't prevent bind on top of another later on. To fix it right way we need to mark _dentry_ as unsuitable for mounting upon; new flag (DCACHE_CANT_MOUNT) is protected by d_flags and i_mutex on the inode in question. Set it (with dont_mount(dentry)) in unlink/rmdir/etc., check (with cant_mount(dentry)) in places in namespace.c that used to check for S_DEAD. Setting S_DEAD is still needed in places where we used to set it (for directories getting killed), since we rely on it for readdir/rmdir race prevention. 2) rename()/mount() protection has another bogosity - we unhash the target before we'd checked that it's not a mountpoint. Fixed. 3) ancient bogosity in pivot_root() - we locked i_mutex on the right directory, but checked S_DEAD on the different (and wrong) one. Noticed and fixed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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420118ca |
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28-Jan-2009 |
Louis Rilling <louis.rilling@kerlabs.com> |
configfs: Rework configfs_depend_item() locking and make lockdep happy configfs_depend_item() recursively locks all inodes mutex from configfs root to the target item, which makes lockdep unhappy. The purpose of this recursive locking is to ensure that the item tree can be safely parsed and that the target item, if found, is not about to leave. This patch reworks configfs_depend_item() locking using configfs_dirent_lock. Since configfs_dirent_lock protects all changes to the configfs_dirent tree, and protects tagging of items to be removed, this lock can be used instead of the inodes mutex lock chain. This needs that the check for dependents be done atomically with CONFIGFS_USET_DROPPING tagging. Now lockdep looks happy with configfs. [ Lifted the setting of s_type into configfs_new_dirent() to satisfy the atomic setting of CONFIGFS_USET_CREATING -- Joel ] Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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e74cc06d |
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28-Jan-2009 |
Louis Rilling <louis.rilling@kerlabs.com> |
configfs: Silence lockdep on mkdir() and rmdir() When attaching default groups (subdirs) of a new group (in mkdir() or in configfs_register()), configfs recursively takes inode's mutexes along the path from the parent of the new group to the default subdirs. This is needed to ensure that the VFS will not race with operations on these sub-dirs. This is safe for the following reasons: - the VFS allows one to lock first an inode and second one of its children (The lock subclasses for this pattern are respectively I_MUTEX_PARENT and I_MUTEX_CHILD); - from this rule any inode path can be recursively locked in descending order as long as it stays under a single mountpoint and does not follow symlinks. Unfortunately lockdep does not know (yet?) how to handle such recursion. I've tried to use Peter Zijlstra's lock_set_subclass() helper to upgrade i_mutexes from I_MUTEX_CHILD to I_MUTEX_PARENT when we know that we might recursively lock some of their descendant, but this usage does not seem to fit the purpose of lock_set_subclass() because it leads to several i_mutex locked with subclass I_MUTEX_PARENT by the same task. >From inside configfs it is not possible to serialize those recursive locking with a top-level one, because mkdir() and rmdir() are already called with inodes locked by the VFS. So using some mutex_lock_nest_lock() is not an option. I am proposing two solutions: 1) one that wraps recursive mutex_lock()s with lockdep_off()/lockdep_on(). 2) (as suggested earlier by Peter Zijlstra) one that puts the i_mutexes recursively locked in different classes based on their depth from the top-level config_group created. This induces an arbitrary limit (MAX_LOCK_DEPTH - 2 == 46) on the nesting of configfs default groups whenever lockdep is activated but this limit looks reasonably high. Unfortunately, this also isolates VFS operations on configfs default groups from the others and thus lowers the chances to detect locking issues. Nobody likes solution 1), which I can understand. This patch implements solution 2). However lockdep is still not happy with configfs_depend_item(). Next patch reworks the locking of configfs_depend_item() and finally makes lockdep happy. [ Note: This hides a few locking interactions with the VFS from lockdep. That was my big concern, because we like lockdep's protection. However, the current state always dumps a spurious warning. The locking is correct, so I tell people to ignore the warning and that we'll keep our eyes on the locking to make sure it stays correct. With this patch, we eliminate the warning. We do lose some of the lockdep protections, but this only means that we still have to keep our eyes on the locking. We're going to do that anyway. -- Joel ] Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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296c2d86 |
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19-Feb-2009 |
Al Viro <viro@zeniv.linux.org.uk> |
constify dentry_operations: configfs Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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436443f0 |
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04-Feb-2009 |
Mark Fasheh <mfasheh@suse.com> |
Revert "configfs: Silence lockdep on mkdir(), rmdir() and configfs_depend_item()" This reverts commit 0e0333429a6280e6eb3c98845e4eed90d5f8078a. I committed this by accident - Joel and Louis are working with the lockdep maintainer to provide a better solution than just turning lockdep off. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: <Joel Becker <joel.becker@oracle.com>
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0e033342 |
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17-Dec-2008 |
Joel Becker <Joel.Becker@oracle.com> |
configfs: Silence lockdep on mkdir(), rmdir() and configfs_depend_item() When attaching default groups (subdirs) of a new group (in mkdir() or in configfs_register()), configfs recursively takes inode's mutexes along the path from the parent of the new group to the default subdirs. This is needed to ensure that the VFS will not race with operations on these sub-dirs. This is safe for the following reasons: - the VFS allows one to lock first an inode and second one of its children (The lock subclasses for this pattern are respectively I_MUTEX_PARENT and I_MUTEX_CHILD); - from this rule any inode path can be recursively locked in descending order as long as it stays under a single mountpoint and does not follow symlinks. Unfortunately lockdep does not know (yet?) how to handle such recursion. I've tried to use Peter Zijlstra's lock_set_subclass() helper to upgrade i_mutexes from I_MUTEX_CHILD to I_MUTEX_PARENT when we know that we might recursively lock some of their descendant, but this usage does not seem to fit the purpose of lock_set_subclass() because it leads to several i_mutex locked with subclass I_MUTEX_PARENT by the same task. >From inside configfs it is not possible to serialize those recursive locking with a top-level one, because mkdir() and rmdir() are already called with inodes locked by the VFS. So using some mutex_lock_nest_lock() is not an option. I am proposing two solutions: 1) one that wraps recursive mutex_lock()s with lockdep_off()/lockdep_on(). 2) (as suggested earlier by Peter Zijlstra) one that puts the i_mutexes recursively locked in different classes based on their depth from the top-level config_group created. This induces an arbitrary limit (MAX_LOCK_DEPTH - 2 == 46) on the nesting of configfs default groups whenever lockdep is activated but this limit looks reasonably high. Unfortunately, this alos isolates VFS operations on configfs default groups from the others and thus lowers the chances to detect locking issues. This patch implements solution 1). Solution 2) looks better from lockdep's point of view, but fails with configfs_depend_item(). This needs to rework the locking scheme of configfs_depend_item() by removing the variable lock recursion depth, and I think that it's doable thanks to the configfs_dirent_lock. For now, let's stick to solution 1). Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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de6bf18e |
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15-Aug-2008 |
Louis Rilling <louis.rilling@kerlabs.com> |
[PATCH] configfs: Consolidate locking around configfs_detach_prep() in configfs_rmdir() It appears that configfs_rmdir() can protect configfs_detach_prep() retries with less calls to {spin,mutex}_{lock,unlock}, and a cleaner code. This patch does not change any behavior, except that it removes two useless lock/unlock pairs having nothing inside to protect and providing a useless barrier. Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <Joel.Becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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70526b67 |
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17-Jun-2008 |
Joel Becker <joel.becker@oracle.com> |
[PATCH] configfs: Pin configfs subsystems separately from new config_items. configfs_mkdir() creates a new item by calling its parent's ->make_item/group() functions. Once that object is created, configfs_mkdir() calls try_module_get() on the new item's module. If it succeeds, the module owning the new item cannot be unloaded, and configfs is safe to reference the item. If the item and the subsystem it belongs to are part of the same module, the subsystem is also pinned. This is the common case. However, if the subsystem is made up of multiple modules, this may not pin the subsystem. Thus, it would be possible to unload the toplevel subsystem module while there is still a child item. Thus, we now try_module_get() the subsystem's module. This only really affects children of the toplevel subsystem group. Deeper children already have their parents pinned. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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99cefda4 |
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27-Jun-2008 |
Louis Rilling <louis.rilling@kerlabs.com> |
[PATCH] configfs: Fix open directory making rmdir() fail When checking for user-created elements under an item to be removed by rmdir(), configfs_detach_prep() counts fake configfs_dirents created by dir_open() as user-created and fails when finding one. It is however perfectly valid to remove a directory that is open. Simply make configfs_detach_prep() skip fake configfs_dirent, like it already does for attributes, and like detach_groups() does. Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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2e2ce171 |
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04-Jul-2008 |
Louis Rilling <louis.rilling@kerlabs.com> |
[PATCH] configfs: Lock new directory inodes before removing on cleanup after failure Once a new configfs directory is created by configfs_attach_item() or configfs_attach_group(), a failure in the remaining initialization steps leads to removing a directory which inode the VFS may have already accessed. This commit adds the necessary inode locking to safely remove configfs directories while cleaning up after a failure. As an advantage, the locking rules of populate_groups() and detach_groups() become the same: the caller must have the group's inode mutex locked. Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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2a109f2a |
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04-Jul-2008 |
Louis Rilling <louis.rilling@kerlabs.com> |
[PATCH] configfs: Prevent userspace from creating new entries under attaching directories process 1: process 2: configfs_mkdir("A") attach_group("A") attach_item("A") d_instantiate("A") populate_groups("A") mutex_lock("A") attach_group("A/B") attach_item("A") d_instantiate("A/B") mkdir("A/B/C") do_path_lookup("A/B/C", LOOKUP_PARENT) ok lookup_create("A/B/C") mutex_lock("A/B") ok configfs_mkdir("A/B/C") ok attach_group("A/C") attach_item("A/C") d_instantiate("A/C") populate_groups("A/C") mutex_lock("A/C") attach_group("A/C/D") attach_item("A/C/D") failure mutex_unlock("A/C") detach_groups("A/C") nothing to do mkdir("A/C/E") do_path_lookup("A/C/E", LOOKUP_PARENT) ok lookup_create("A/C/E") mutex_lock("A/C") ok configfs_mkdir("A/C/E") ok detach_item("A/C") d_delete("A/C") mutex_unlock("A") detach_groups("A") mutex_lock("A/B") detach_group("A/B") detach_groups("A/B") nothing since no _default_ group detach_item("A/B") mutex_unlock("A/B") d_delete("A/B") detach_item("A") d_delete("A") Two bugs: 1/ "A/B/C" and "A/C/E" are created, but never removed while their parent are removed in the end. The same could happen with symlink() instead of mkdir(). 2/ "A" and "A/C" inodes are not locked while detach_item() is called on them, which may probably confuse VFS. This commit fixes 1/, tagging new directories with CONFIGFS_USET_CREATING before building the inode and instantiating the dentry, and validating the whole group+default groups hierarchy in a second pass by clearing CONFIGFS_USET_CREATING. mkdir(), symlink(), lookup(), and dir_open() simply return -ENOENT if called in (or linking to) a directory tagged with CONFIGFS_USET_CREATING. This does not prevent userspace from calling stat() successfuly on such directories, but this prevents userspace from adding (children to | symlinking from/to | read/write attributes of | listing the contents of) not validated items. In other words, userspace will not interact with the subsystem on a new item until the new item creation completes correctly. It was first proposed to re-use CONFIGFS_USET_IN_MKDIR instead of a new flag CONFIGFS_USET_CREATING, but this generated conflicts when checking the target of a new symlink: a valid target directory in the middle of attaching a new user-created child item could be wrongly detected as being attached. 2/ is fixed by next commit. Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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9a73d78c |
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20-Jun-2008 |
Louis Rilling <louis.rilling@kerlabs.com> |
[PATCH] configfs: Fix failing symlink() making rmdir() fail On a similar pattern as mkdir() vs rmdir(), a failing symlink() may make rmdir() fail for the symlink's parent and the symlink's target as well. failing symlink() making target's rmdir() fail: process 1: process 2: symlink("A/S" -> "B") allow_link() create_link() attach to "B" links list rmdir("B") detach_prep("B") error because of new link configfs_create_link("A", "S") error (eg -ENOMEM) failing symlink() making parent's rmdir() fail: process 1: process 2: symlink("A/D/S" -> "B") allow_link() create_link() attach to "B" links list configfs_create_link("A/D", "S") make_dirent("A/D", "S") rmdir("A") detach_prep("A") detach_prep("A/D") error because of "S" create("S") error (eg -ENOMEM) We cannot use the same solution as for mkdir() vs rmdir(), since rmdir() on the target cannot wait on the i_mutex of the new symlink's parent without risking a deadlock (with other symlink() or sys_rename()). Instead we define a global mutex protecting all configfs symlinks attachment, so that rmdir() can avoid the races above. Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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4768e9b1 |
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23-Jun-2008 |
Louis Rilling <louis.rilling@kerlabs.com> |
[PATCH] configfs: Fix symlink() to a removing item The rule for configfs symlinks is that symlinks always point to valid config_items, and prevent the target from being removed. However, configfs_symlink() only checks that it can grab a reference on the target item, without ensuring that it remains alive until the symlink is correctly attached. This patch makes configfs_symlink() fail whenever the target is being removed, using the CONFIGFS_USET_DROPPING flag set by configfs_detach_prep() and protected by configfs_dirent_lock. This patch introduces a similar (weird?) behavior as with mkdir failures making rmdir fail: if symlink() races with rmdir() of the parent directory (or its youngest user-created ancestor if parent is a default group) or rmdir() of the target directory, and then fails in configfs_create(), this can make the racing rmdir() fail despite the concerned directory having no user-created entry (resp. no symlink pointing to it or one of its default groups) in the end. This behavior is fixed in later patches. Signed-off-by: Louis Rilling <louis.rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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dacdd0e0 |
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17-Jul-2008 |
Joel Becker <joel.becker@oracle.com> |
[PATCH] configfs: Include linux/err.h in linux/configfs.h We now use PTR_ERR() in the ->make_item() and ->make_group() operations. Folks including configfs.h need err.h. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
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a6795e9e |
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17-Jul-2008 |
Joel Becker <joel.becker@oracle.com> |
configfs: Allow ->make_item() and ->make_group() to return detailed errors. The configfs operations ->make_item() and ->make_group() currently return a new item/group. A return of NULL signifies an error. Because of this, -ENOMEM is the only return code bubbled up the stack. Multiple folks have requested the ability to return specific error codes when these operations fail. This patch adds that ability by changing the ->make_item/group() ops to return ERR_PTR() values. These errors are bubbled up appropriately. NULL returns are changed to -ENOMEM for compatibility. Also updated are the in-kernel users of configfs. This is a rework of reverted commit 11c3b79218390a139f2d474ee1e983a672d5839a. Signed-off-by: Joel Becker <joel.becker@oracle.com>
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f89ab861 |
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17-Jul-2008 |
Joel Becker <joel.becker@oracle.com> |
Revert "configfs: Allow ->make_item() and ->make_group() to return detailed errors." This reverts commit 11c3b79218390a139f2d474ee1e983a672d5839a. The code will move to PTR_ERR(). Signed-off-by: Joel Becker <joel.becker@oracle.com>
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11c3b792 |
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12-Jun-2008 |
Joel Becker <joel.becker@oracle.com> |
configfs: Allow ->make_item() and ->make_group() to return detailed errors. The configfs operations ->make_item() and ->make_group() currently return a new item/group. A return of NULL signifies an error. Because of this, -ENOMEM is the only return code bubbled up the stack. Multiple folks have requested the ability to return specific error codes when these operations fail. This patch adds that ability by changing the ->make_item/group() ops to return an int. Also updated are the in-kernel users of configfs. Signed-off-by: Joel Becker <joel.becker@oracle.com>
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6d8344ba |
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16-Jun-2008 |
Louis Rilling <Louis.Rilling@kerlabs.com> |
configfs: Fix failing mkdir() making racing rmdir() fail When fixing the rename() vs rmdir() deadlock, we stopped locking default groups' inodes in configfs_detach_prep(), letting racing mkdir() in default groups proceed concurrently. This enables races like below happen, which leads to a failing mkdir() making rmdir() fail, despite the group to remove having no user-created directory under it in the end. process A: process B: /* PWD=A/B */ mkdir("C") make_item("C") attach_group("C") rmdir("A") detach_prep("A") detach_prep("B") error because of "C" return -ENOTEMPTY attach_group("C/D") error (eg -ENOMEM) return -ENOMEM This patch prevents such scenarii by making rmdir() wait as long as detach_prep() fails because a racing mkdir() is in the middle of attach_group(). To achieve this, mkdir() sets a flag CONFIGFS_USET_IN_MKDIR in parent's configfs_dirent before calling attach_group(), and clears the flag once attach_group() is done. detach_prep() fails with -EAGAIN whenever the flag is hit and returns the guilty inode's mutex so that rmdir() can wait on it. Signed-off-by: Louis Rilling <Louis.Rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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b3e76af8 |
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16-Jun-2008 |
Louis Rilling <Louis.Rilling@kerlabs.com> |
configfs: Fix deadlock with racing rmdir() and rename() This patch fixes the deadlock between racing sys_rename() and configfs_rmdir(). The idea is to avoid locking i_mutexes of default groups in configfs_detach_prep(), and rely instead on the new configfs_dirent_lock to protect against configfs_dirent's linkage mutations. To ensure that an mkdir() racing with rmdir() will not create new items in a to-be-removed default group, we make configfs_new_dirent() check for the CONFIGFS_USET_DROPPING flag right before linking the new dirent, and return error if the flag is set. This makes racing mkdir()/symlink()/dir_open() fail in places where errors could already happen, resp. in (attach_item()|attach_group())/create_link()/new_dirent(). configfs_depend() remains safe since it locks all the path from configfs root, and is thus mutually exclusive with rmdir(). An advantage of this is that now detach_groups() unconditionnaly takes the default groups i_mutex, which makes it more consistent with populate_groups(). Signed-off-by: Louis Rilling <Louis.Rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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107ed40b |
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16-Jun-2008 |
Louis Rilling <Louis.Rilling@kerlabs.com> |
configfs: Make configfs_new_dirent() return error code instead of NULL This patch makes configfs_new_dirent return negative error code instead of NULL, which will be useful in the next patch to differentiate ENOMEM from ENOENT. Signed-off-by: Louis Rilling <Louis.Rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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5301a77d |
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16-Jun-2008 |
Louis Rilling <Louis.Rilling@kerlabs.com> |
configfs: Protect configfs_dirent s_links list mutations Symlinks to a config_item are listed under its configfs_dirent s_links, but the list mutations are not protected by any common lock. This patch uses the configfs_dirent_lock spinlock to add the necessary protection. Note: we should also protect the list_empty() test in configfs_detach_prep() but 1/ the lock should not be released immediately because nothing would prevent the list from being filled after a successful list_empty() test, making the problem tricky, 2/ this will be solved by the rmdir() vs rename() deadlock bugfix. Signed-off-by: Louis Rilling <Louis.Rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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6f610764 |
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16-Jun-2008 |
Louis Rilling <Louis.Rilling@kerlabs.com> |
configfs: Introduce configfs_dirent_lock This patch introduces configfs_dirent_lock spinlock to protect configfs_dirent traversals against linkage mutations (add/del/move). This will allow configfs_detach_prep() to avoid locking i_mutexes. Locking rules for configfs_dirent linkage mutations are the same plus the requirement of taking configfs_dirent_lock. For configfs_dirent walking, one can either take appropriate i_mutex as before, or take configfs_dirent_lock. The spinlock could actually be a mutex, but the critical sections are either O(1) or should not be too long (default groups walking in last patch). ChangeLog: - Clarify the comment on configfs_dirent_lock usage - Move sd->s_element init before linking the new dirent - In lseek(), do not release configfs_dirent_lock before the dirent is relinked. Signed-off-by: Louis Rilling <Louis.Rilling@kerlabs.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
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ba611edf |
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25-Dec-2007 |
Joonwoo Park <joonwpark81@gmail.com> |
configfs: dir.c fix possible recursive locking configfs_register_subsystem() with default_groups triggers recursive locking. it seems that mutex_lock_nested is needed. ============================================= [ INFO: possible recursive locking detected ] 2.6.24-rc6 #141 --------------------------------------------- swapper/1 is trying to acquire lock: (&sb->s_type->i_mutex_key#3){--..}, at: [<c40ca76f>] configfs_attach_group+0x4f/0x190 but task is already holding lock: (&sb->s_type->i_mutex_key#3){--..}, at: [<c40ca9d5>] configfs_register_subsystem+0x55/0x130 other info that might help us debug this: 1 lock held by swapper/1: #0: (&sb->s_type->i_mutex_key#3){--..}, at: [<c40ca9d5>] configfs_register_subsystem+0x55/0x130 stack backtrace: Pid: 1, comm: swapper Not tainted 2.6.24-rc6 #141 [<c40053ba>] show_trace_log_lvl+0x1a/0x30 [<c4005e82>] show_trace+0x12/0x20 [<c400687e>] dump_stack+0x6e/0x80 [<c404ec72>] __lock_acquire+0xe62/0x1120 [<c404efb2>] lock_acquire+0x82/0xa0 [<c43fdad8>] mutex_lock_nested+0x98/0x2e0 [<c40ca76f>] configfs_attach_group+0x4f/0x190 [<c40caa46>] configfs_register_subsystem+0xc6/0x130 [<c45c8186>] init_netconsole+0x2b6/0x300 [<c45a75f2>] kernel_init+0x142/0x320 [<c4004fb3>] kernel_thread_helper+0x7/0x14 ======================= Signed-off-by: Joonwoo Park <joonwpark81@gmail.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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ce8d2cdf |
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17-Oct-2007 |
Dave Hansen <haveblue@us.ibm.com> |
r/o bind mounts: filesystem helpers for custom 'struct file's Why do we need r/o bind mounts? This feature allows a read-only view into a read-write filesystem. In the process of doing that, it also provides infrastructure for keeping track of the number of writers to any given mount. This has a number of uses. It allows chroots to have parts of filesystems writable. It will be useful for containers in the future because users may have root inside a container, but should not be allowed to write to somefilesystems. This also replaces patches that vserver has had out of the tree for several years. It allows security enhancement by making sure that parts of your filesystem read-only (such as when you don't trust your FTP server), when you don't want to have entire new filesystems mounted, or when you want atime selectively updated. I've been using the following script to test that the feature is working as desired. It takes a directory and makes a regular bind and a r/o bind mount of it. It then performs some normal filesystem operations on the three directories, including ones that are expected to fail, like creating a file on the r/o mount. This patch: Some filesystems forego the vfs and may_open() and create their own 'struct file's. This patch creates a couple of helper functions which can be used by these filesystems, and will provide a unified place which the r/o bind mount code may patch. Also, rename an existing, static-scope init_file() to a less generic name. Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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631d1feb |
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18-Jun-2007 |
Joel Becker <joel.becker@oracle.com> |
configfs: config item dependancies. Sometimes other drivers depend on particular configfs items. For example, ocfs2 mounts depend on a heartbeat region item. If that region item is removed with rmdir(2), the ocfs2 mount must BUG or go readonly. Not happy. This provides two additional API calls: configfs_depend_item() and configfs_undepend_item(). A client driver can call configfs_depend_item() on an existing item to tell configfs that it is depended on. configfs will then return -EBUSY from rmdir(2) for that item. When the item is no longer depended on, the client driver calls configfs_undepend_item() on it. These API cannot be called underneath any configfs callbacks, as they will conflict. They can block and allocate. A client driver probably shouldn't calling them of its own gumption. Rather it should be providing an API that external subsystems call. How does this work? Imagine the ocfs2 mount process. When it mounts, it asks for a heart region item. This is done via a call into the heartbeat code. Inside the heartbeat code, the region item is looked up. Here, the heartbeat code calls configfs_depend_item(). If it succeeds, then heartbeat knows the region is safe to give to ocfs2. If it fails, it was being torn down anyway, and heartbeat can gracefully pass up an error. [ Fixed some bad whitespace in configfs.txt. --Mark ] Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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299894cc |
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06-Oct-2006 |
Joel Becker <joel.becker@oracle.com> |
configfs: accessing item hierarchy during rmdir(2) Add a notification callback, ops->disconnect_notify(). It has the same prototype as ->drop_item(), but it will be called just before the item linkage is broken. This way, configfs users who want to do work while the object is still in the heirarchy have a chance. Client drivers will still need to config_item_put() in their ->drop_item(), if they implement it. They need do nothing in ->disconnect_notify(). They don't have to provide it if they don't care. But someone who wants to be notified before ci_parent is set to NULL can now be notified. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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e6bd07ae |
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07-Jul-2007 |
Joel Becker <joel.becker@oracle.com> |
configfs: Convert subsystem semaphore to mutex Convert the su_sem member of struct configfs_subsystem to a struct mutex, as that's what it is. Also convert all the users and update Documentation/configfs.txt and Documentation/configfs_example.c accordingly. [ Conflict in fs/dlm/config.c with commit 3168b0780d06ace875696f8a648d04d6089654e5 manually resolved. --Mark ] Inspired-by: Satyam Sharma <ssatyam@cse.iitk.ac.in> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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afdf04ea |
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05-Mar-2007 |
Joel Becker <joel.becker@oracle.com> |
configfs: add missing mutex_unlock() d_alloc() failure in configfs_register_subsystem() would fail to unlock the mutex taken above. Reorganize the exit path to ensure the unlock happens. Reported-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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754661f1 |
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12-Feb-2007 |
Arjan van de Ven <arjan@linux.intel.com> |
[PATCH] mark struct inode_operations const 1 Many struct inode_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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c3762229 |
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10-Feb-2007 |
Robert P. J. Day <rpjday@mindspring.com> |
[PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc(). Replace appropriate pairs of "kmem_cache_alloc()" + "memset(0)" with the corresponding "kmem_cache_zalloc()" call. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: Roland McGrath <roland@redhat.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Greg KH <greg@kroah.com> Acked-by: Joel Becker <Joel.Becker@oracle.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Jan Kara <jack@ucw.cz> Cc: Michael Halcrow <mhalcrow@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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867fa491 |
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08-Dec-2006 |
Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> |
[PATCH] configfs: change uses of f_{dentry, vfsmnt} to use f_path Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the configfs filesystem. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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58d206c2 |
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19-Nov-2006 |
Adrian Bunk <bunk@stusta.de> |
configfs: make configfs_dirent_exists() static This patch makes the needlessly global configfs_dirent_exists() static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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55ed1602 |
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20-Oct-2006 |
Mark Fasheh <mark.fasheh@oracle.com> |
configfs: mutex_lock_nested() fix configfs_unregister_subsystem() nests a pair of inode i_mutex acquisitions, and thus needs annotation via mutex_lock_nested(). Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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d8c76e6f |
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01-Oct-2006 |
Dave Hansen <haveblue@us.ibm.com> |
[PATCH] r/o bind mount prepwork: inc_nlink() helper This is mostly included for parity with dec_nlink(), where we will have some more hooks. This one should stay pretty darn straightforward for now. Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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b4c98f62 |
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13-Sep-2006 |
Joel Becker <joel.becker@oracle.com> |
configfs: Prevent duplicate subsystem names. For all child objects, creation comes through mkdir(2), so duplicate names are prevented. Subsystems, though, are registered by client drivers at init_module()/__init time. This patch prevents duplicate subsystem names. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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e7515d06 |
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10-Mar-2006 |
Joel Becker <joel.becker@oracle.com> |
configfs: Clear up a few extra spaces where there should be TABs. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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f116629d |
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26-Jun-2006 |
Akinobu Mita <mita@miraclelinux.com> |
[PATCH] fs: use list_move() This patch converts the combination of list_del(A) and list_add(A, B) to list_move(A, B) under fs/. Cc: Ian Kent <raven@themaw.net> Acked-by: Joel Becker <joel.becker@oracle.com> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: Hans Reiser <reiserfs-dev@namesys.com> Cc: Urban Widmark <urban@teststation.com> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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eed7a0db |
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11-Apr-2006 |
Joel Becker <joel.becker@oracle.com> |
configfs: configfs_mkdir() failed to cleanup linkage. If configfs_mkdir() errored in certain ways after the parent<->child linkage was already created, it would not undo the linkage. Also, comment the reference counting for clarity. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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84efad1a |
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27-Mar-2006 |
Joel Becker <joel.becker@oracle.com> |
configfs: Fix a reference leak in configfs_mkdir(). configfs_mkdir() failed to release the working parent reference in most exit paths. Also changed the exit path for readability. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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cbca692c |
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22-Mar-2006 |
Eric Sesterhenn <snakebyte@gmx.de> |
[PATCH] Bogus NULL pointer check in fs/configfs/dir.c We check the "group" pointer after we dereference it. This check is bogus, as it cannot be NULL coming in. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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4b6f5d20 |
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28-Mar-2006 |
Arjan van de Ven <arjan@infradead.org> |
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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3d0f89bb |
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25-Jan-2006 |
Joel Becker <joel.becker@oracle.com> |
configfs: Add permission and ownership to configfs objects. configfs always made item and attribute ownership root.root and permissions based on a umask of 022. Add ->setattr() to allow chown(2)/chmod(2), and persist the changes for the lifetime of the items and attributes. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
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1b1dcc1b |
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09-Jan-2006 |
Jes Sorensen <jes@sgi.com> |
[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem This patch converts the inode semaphore to a mutex. I have tested it on XFS and compiled as much as one can consider on an ia64. Anyway your luck with it might be different. Modified-by: Ingo Molnar <mingo@elte.hu> (finished the conversion) Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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7063fbf2 |
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15-Dec-2005 |
Joel Becker <joel.becker@oracle.com> |
[PATCH] configfs: User-driven configuration filesystem Configfs, a file system for userspace-driven kernel object configuration. The OCFS2 stack makes extensive use of this for propagation of cluster configuration information into kernel. Signed-off-by: Joel Becker <joel.becker@oracle.com>
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