Commit Graph

246 Commits

Author SHA1 Message Date
Sishuai Gong
c42dd069be 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>
2021-08-25 07:58:49 +02:00
Christoph Hellwig
d07f132a22 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>
2021-08-25 07:58:46 +02:00
Christoph Hellwig
899587c8d0 configfs: simplify the configfs_dirent_is_ready
Return the error directly instead of using a goto.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-25 07:43:55 +02:00
Christoph Hellwig
417b962dde 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>
2021-08-25 07:42:44 +02:00
Bart Van Assche
769f526767 configfs: restore the kernel v5.13 text attribute write behavior
Instead of appending new text attribute data at the offset specified by the
write() system call, only pass the newly written data to the .store()
callback.

Reported-by: Bodo Stroesser <bostroesser@gmail.com>
Tested-by: Bodo Stroesser <bostroesser@gmail.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-08-09 16:56:00 +02:00
Bart Van Assche
420405ecde configfs: fix the read and write iterators
Commit 7fe1e79b59 ("configfs: implement the .read_iter and .write_iter
methods") changed the simple_read_from_buffer() calls into copy_to_iter()
calls and the simple_write_to_buffer() calls into copy_from_iter() calls.
The simple*buffer() methods update the file offset (*ppos) but the read
and write iterators not yet. Make the read and write iterators update the
file offset (iocb->ki_pos).

This patch has been tested as follows:

 # modprobe target_core_user
 # dd if=/sys/kernel/config/target/dbroot bs=1
/var/target
12+0 records in
12+0 records out
12 bytes copied, 9.5539e-05 s, 126 kB/s

 # cd /sys/kernel/config/acpi/table
 # mkdir test
 # cd test
 # dmesg -c >/dev/null; printf 'SSDT\x8\0\0\0abcdefghijklmnopqrstuvwxyz' | dd of=aml bs=1; dmesg -c
34+0 records in
34+0 records out
34 bytes copied, 0.010627 s, 3.2 kB/s
[  261.056551] ACPI configfs: invalid table length

Reported-by: Yanko Kaneti <yaneti@declera.com>
Cc: Yanko Kaneti <yaneti@declera.com>
Fixes: 7fe1e79b59 ("configfs: implement the .read_iter and .write_iter methods")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-07-13 20:56:24 +02:00
Linus Torvalds
ced4cca754 configfs updates for Linux 5.13
- fix a memleak in configfs_release_bin_file (Chung-Chiang Cheng)
  - implement the .read_iter and .write_iter (Bart Van Assche)
  - minor cleanups (Bart Van Assche, me)
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Merge tag 'configfs-5.13' of git://git.infradead.org/users/hch/configfs

Pull configfs updates from Christoph Hellwig:

 - fix a memleak in configfs_release_bin_file (Chung-Chiang Cheng)

 - implement the .read_iter and .write_iter (Bart Van Assche)

 - minor cleanups (Bart Van Assche, me)

* tag 'configfs-5.13' of git://git.infradead.org/users/hch/configfs:
  configfs: simplify configfs_release_bin_file
  configfs: fix memleak in configfs_release_bin_file
  configfs: implement the .read_iter and .write_iter methods
  configfs: drop pointless kerneldoc comments
  configfs: fix the kerneldoc comment for configfs_create_bin_file
2021-07-02 14:13:21 -07:00
Christoph Hellwig
c1e3dbe981 fs: move ramfs_aops to libfs
Move the ramfs aops to libfs and reuse them for kernfs and configfs.
Thosw two did not wire up ->set_page_dirty before and now get
__set_page_dirty_no_writeback, which is the right one for no-writeback
address_space usage.

Drop the now unused exports of the libfs helpers only used for ramfs-style
pagecache usage.

Link: https://lkml.kernel.org/r/20210614061512.3966143-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:48 -07:00
Christoph Hellwig
c886fa3cf6 configfs: simplify configfs_release_bin_file
Remove the clearing of various fields just before freeing the
buffer structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-22 09:46:28 +02:00
Chung-Chiang Cheng
3c252b087d configfs: fix memleak in configfs_release_bin_file
When reading binary attributes in progress, buffer->bin_buffer is setup in
configfs_read_bin_file() but never freed.

Fixes: 03607ace80 ("configfs: implement binary attributes")
Signed-off-by: Chung-Chiang Cheng <cccheng@synology.com>
[hch: move the vfree rather than duplicating it]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-22 09:46:26 +02:00
Bart Van Assche
7fe1e79b59 configfs: implement the .read_iter and .write_iter methods
Configfs is one of the few filesystems that does not yet support the
.read_iter and .write_iter callbacks. This patch adds support for these
methods in configfs.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
[hch: split out a separate fix]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-05-25 10:30:56 +02:00
Christoph Hellwig
44b9a000df configfs: drop pointless kerneldoc comments
file.c has a bunch of kerneldoc comments for static functions that do not
document any API but just list what is done.  Drop them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-05-25 10:30:31 +02:00
Bart Van Assche
dd33f1f7aa configfs: fix the kerneldoc comment for configfs_create_bin_file
Mention the correct argument name.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-05-25 10:30:31 +02:00
Masahiro Yamada
fa60ce2cb4 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>
2021-05-07 00:26:34 -07:00
Daiyue Zhang
14fbbc8297 configfs: fix a use-after-free in __configfs_open_file
Commit b0841eefd9 ("configfs: provide exclusion between IO and removals")
uses ->frag_dead to mark the fragment state, thus no bothering with extra
refcount on config_item when opening a file. The configfs_get_config_item
was removed in __configfs_open_file, but not with config_item_put. So the
refcount on config_item will lost its balance, causing use-after-free
issues in some occasions like this:

Test:
1. Mount configfs on /config with read-only items:
drwxrwx--- 289 root   root            0 2021-04-01 11:55 /config
drwxr-xr-x   2 root   root            0 2021-04-01 11:54 /config/a
--w--w--w-   1 root   root         4096 2021-04-01 11:53 /config/a/1.txt
......

2. Then run:
for file in /config
do
echo $file
grep -R 'key' $file
done

3. __configfs_open_file will be called in parallel, the first one
got called will do:
if (file->f_mode & FMODE_READ) {
	if (!(inode->i_mode & S_IRUGO))
		goto out_put_module;
			config_item_put(buffer->item);
				kref_put()
					package_details_release()
						kfree()

the other one will run into use-after-free issues like this:
BUG: KASAN: use-after-free in __configfs_open_file+0x1bc/0x3b0
Read of size 8 at addr fffffff155f02480 by task grep/13096
CPU: 0 PID: 13096 Comm: grep VIP: 00 Tainted: G        W       4.14.116-kasan #1
TGID: 13096 Comm: grep
Call trace:
dump_stack+0x118/0x160
kasan_report+0x22c/0x294
__asan_load8+0x80/0x88
__configfs_open_file+0x1bc/0x3b0
configfs_open_file+0x28/0x34
do_dentry_open+0x2cc/0x5c0
vfs_open+0x80/0xe0
path_openat+0xd8c/0x2988
do_filp_open+0x1c4/0x2fc
do_sys_open+0x23c/0x404
SyS_openat+0x38/0x48

Allocated by task 2138:
kasan_kmalloc+0xe0/0x1ac
kmem_cache_alloc_trace+0x334/0x394
packages_make_item+0x4c/0x180
configfs_mkdir+0x358/0x740
vfs_mkdir2+0x1bc/0x2e8
SyS_mkdirat+0x154/0x23c
el0_svc_naked+0x34/0x38

Freed by task 13096:
kasan_slab_free+0xb8/0x194
kfree+0x13c/0x910
package_details_release+0x524/0x56c
kref_put+0xc4/0x104
config_item_put+0x24/0x34
__configfs_open_file+0x35c/0x3b0
configfs_open_file+0x28/0x34
do_dentry_open+0x2cc/0x5c0
vfs_open+0x80/0xe0
path_openat+0xd8c/0x2988
do_filp_open+0x1c4/0x2fc
do_sys_open+0x23c/0x404
SyS_openat+0x38/0x48
el0_svc_naked+0x34/0x38

To fix this issue, remove the config_item_put in
__configfs_open_file to balance the refcount of config_item.

Fixes: b0841eefd9 ("configfs: provide exclusion between IO and removals")
Signed-off-by: Daiyue Zhang <zhangdaiyue1@huawei.com>
Signed-off-by: Yi Chen <chenyi77@huawei.com>
Signed-off-by: Ge Qiu <qiuge@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-03-11 12:13:48 +01:00
Christian Brauner
549c729771
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>
2021-01-24 14:27:20 +01:00
Christian Brauner
47291baa8d
namei: make permission helpers idmapped mount aware
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-6-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>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Alex Shi
65cdb4a214 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>
2020-11-14 10:22:45 +01:00
Randy Dunlap
ce9bebe683 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>
2020-10-16 11:11:19 -07:00
Gustavo A. R. Silva
df561f6688 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>
2020-08-23 17:36:59 -05:00
Linus Torvalds
b23c4771ff A fair amount of stuff this time around, dominated by yet another massive
set from Mauro toward the completion of the RST conversion.  I *really*
 hope we are getting close to the end of this.  Meanwhile, those patches
 reach pretty far afield to update document references around the tree;
 there should be no actual code changes there.  There will be, alas, more of
 the usual trivial merge conflicts.
 
 Beyond that we have more translations, improvements to the sphinx
 scripting, a number of additions to the sysctl documentation, and lots of
 fixes.
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Merge tag 'docs-5.8' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
Mauro Carvalho Chehab
982649915d docs: filesystems: convert configfs.txt to ReST
- Add a SPDX header;
- Adjust document and section titles;
- Use copyright symbol;
- Some whitespace fixes and new line breaks;
- Mark literal blocks as such;
- Add it to filesystems/index.rst.

Also, as this file is alone on its own dir, and it doesn't
seem too likely that other documents will follow it, let's
move it to the filesystems/ root documentation dir.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/c2424ec2ad4d735751434ff7f52144c44aa02d5a.1588021877.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-05 09:23:25 -06:00
Xiyu Yang
8aebfffacf 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>
2020-04-27 08:17:10 +02:00
Amir Goldstein
eb31e2f63d utimes: Clamp the timestamps in notify_change()
Push clamping timestamps into notify_change(), so in-kernel
callers like nfsd and overlayfs will get similar timestamp
set behavior as utimes.

AV: get rid of clamping in ->setattr() instances; we don't need
to bother with that there, with notify_change() doing normalization
in all cases now (it already did for implicit case, since current_time()
clamps).

Suggested-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 42e729b9dd ("utimes: Clamp the timestamps before update")
Cc: stable@vger.kernel.org # v5.4
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-12-08 19:10:50 -05:00
Honggang Li
e2f238f7d5 configfs: calculate the depth of parent item
When create symbolic link, create_link should calculate the depth
of the parent item. However, both the first and second parameters
of configfs_get_target_path had been set to the target. Broken
symbolic link created.

$ targetcli ls /
o- / ............................................................. [...]
  o- backstores .................................................. [...]
  | o- block ...................................... [Storage Objects: 0]
  | o- fileio ..................................... [Storage Objects: 2]
  | | o- vdev0 .......... [/dev/ramdisk1 (16.0MiB) write-thru activated]
  | | | o- alua ....................................... [ALUA Groups: 1]
  | | |   o- default_tg_pt_gp ........... [ALUA state: Active/optimized]
  | | o- vdev1 .......... [/dev/ramdisk2 (16.0MiB) write-thru activated]
  | |   o- alua ....................................... [ALUA Groups: 1]
  | |     o- default_tg_pt_gp ........... [ALUA state: Active/optimized]
  | o- pscsi ...................................... [Storage Objects: 0]
  | o- ramdisk .................................... [Storage Objects: 0]
  o- iscsi ................................................ [Targets: 0]
  o- loopback ............................................. [Targets: 0]
  o- srpt ................................................. [Targets: 2]
  | o- ib.e89a8f91cb3200000000000000000000 ............... [no-gen-acls]
  | | o- acls ................................................ [ACLs: 2]
  | | | o- ib.e89a8f91cb3200000000000000000000 ........ [Mapped LUNs: 2]
  | | | | o- mapped_lun0 ............................. [BROKEN LUN LINK]
  | | | | o- mapped_lun1 ............................. [BROKEN LUN LINK]
  | | | o- ib.e89a8f91cb3300000000000000000000 ........ [Mapped LUNs: 2]
  | | |   o- mapped_lun0 ............................. [BROKEN LUN LINK]
  | | |   o- mapped_lun1 ............................. [BROKEN LUN LINK]
  | | o- luns ................................................ [LUNs: 2]
  | |   o- lun0 ...... [fileio/vdev0 (/dev/ramdisk1) (default_tg_pt_gp)]
  | |   o- lun1 ...... [fileio/vdev1 (/dev/ramdisk2) (default_tg_pt_gp)]
  | o- ib.e89a8f91cb3300000000000000000000 ............... [no-gen-acls]
  |   o- acls ................................................ [ACLs: 0]
  |   o- luns ................................................ [LUNs: 0]
  o- vhost ................................................ [Targets: 0]

Fixes: e9c03af21c ("configfs: calculate the symlink target only once")
Signed-off-by: Honggang Li <honli@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-11-06 18:36:01 +01:00
Linus Torvalds
c9fe5630da configfs updates for 5.4:
- fix a symlink deadlock (Al Viro)
  - various cleanups (Al Viro, me)
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Merge tag 'configfs-for-5.4' of git://git.infradead.org/users/hch/configfs

Pull configfs updates from Christoph Hellwig:

 - fix a symlink deadlock (Al Viro)

 - various cleanups (Al Viro, me)

* tag 'configfs-for-5.4' of git://git.infradead.org/users/hch/configfs:
  configfs: calculate the symlink target only once
  configfs: make configfs_create() return inode
  configfs: factor dirent removal into helpers
  configfs: fix a deadlock in configfs_symlink()
2019-09-19 13:09:28 -07:00
Linus Torvalds
cfb82e1df8 y2038: add inode timestamp clamping
This series from Deepa Dinamani adds a per-superblock minimum/maximum
 timestamp limit for a file system, and clamps timestamps as they are
 written, to avoid random behavior from integer overflow as well as having
 different time stamps on disk vs in memory.
 
 At mount time, a warning is now printed for any file system that can
 represent current timestamps but not future timestamps more than 30
 years into the future, similar to the arbitrary 30 year limit that was
 added to settimeofday().
 
 This was picked as a compromise to warn users to migrate to other file
 systems (e.g. ext4 instead of ext3) when they need the file system to
 survive beyond 2038 (or similar limits in other file systems), but not
 get in the way of normal usage.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'y2038-vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 vfs updates from Arnd Bergmann:
 "Add inode timestamp clamping.

  This series from Deepa Dinamani adds a per-superblock minimum/maximum
  timestamp limit for a file system, and clamps timestamps as they are
  written, to avoid random behavior from integer overflow as well as
  having different time stamps on disk vs in memory.

  At mount time, a warning is now printed for any file system that can
  represent current timestamps but not future timestamps more than 30
  years into the future, similar to the arbitrary 30 year limit that was
  added to settimeofday().

  This was picked as a compromise to warn users to migrate to other file
  systems (e.g. ext4 instead of ext3) when they need the file system to
  survive beyond 2038 (or similar limits in other file systems), but not
  get in the way of normal usage"

* tag 'y2038-vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
  ext4: Reduce ext4 timestamp warnings
  isofs: Initialize filesystem timestamp ranges
  pstore: fs superblock limits
  fs: omfs: Initialize filesystem timestamp ranges
  fs: hpfs: Initialize filesystem timestamp ranges
  fs: ceph: Initialize filesystem timestamp ranges
  fs: sysv: Initialize filesystem timestamp ranges
  fs: affs: Initialize filesystem timestamp ranges
  fs: fat: Initialize filesystem timestamp ranges
  fs: cifs: Initialize filesystem timestamp ranges
  fs: nfs: Initialize filesystem timestamp ranges
  ext4: Initialize timestamps limits
  9p: Fill min and max timestamps in sb
  fs: Fill in max and min timestamps in superblock
  utimes: Clamp the timestamps before update
  mount: Add mount warning for impending timestamp expiry
  timestamp_truncate: Replace users of timespec64_trunc
  vfs: Add timestamp_truncate() api
  vfs: Add file timestamp range support
2019-09-19 09:42:37 -07:00
Al Viro
e9c03af21c 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>
2019-09-11 12:46:14 +02:00
Al Viro
2743c515a1 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>
2019-09-11 12:46:10 +02:00
Christoph Hellwig
1cf7a003b0 configfs: factor dirent removal into helpers
Lots of duplicated code that benefits from a little consolidation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-11 12:45:57 +02:00
Al Viro
351e5d869e configfs: fix a deadlock in configfs_symlink()
Configfs abuses symlink(2).  Unlike the normal filesystems, it
wants the target resolved at symlink(2) time, like link(2) would've
done.  The problem is that ->symlink() is called with the parent
directory locked exclusive, so resolving the target inside the
->symlink() is easily deadlocked.

Short of really ugly games in sys_symlink() itself, all we can
do is to unlock the parent before resolving the target and
relock it after.  However, that invalidates the checks done
by the caller of ->symlink(), so we have to
	* check that dentry is still where it used to be
(it couldn't have been moved, but it could've been unhashed)
	* recheck that it's still negative (somebody else
might've successfully created a symlink with the same name
while we were looking the target up)
	* recheck the permissions on the parent directory.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-11 12:45:49 +02:00
Al Viro
b0841eefd9 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>
2019-09-04 22:33:51 +02:00
Al Viro
47320fbe11 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>
2019-09-02 22:10:44 +02:00
Al Viro
f19e4ed1e1 configfs_register_group() shouldn't be (and isn't) called in rmdirable parts
revert cc57c07343 "configfs: fix registered group removal"
It was an attempt to handle something that fundamentally doesn't
work - configfs_register_group() should never be done in a part
of tree that can be rmdir'ed.  And in mainline it never had been,
so let's not borrow trouble; the fix was racy anyway, it would take
a lot more to make that work and desired semantics is not clear.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-02 22:10:44 +02:00
Al Viro
ff4dd08197 configfs: stash the data we need into configfs_buffer at open time
simplifies the ->read()/->write()/->release() instances nicely

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-02 22:10:43 +02:00
Deepa Dinamani
3818c1907a timestamp_truncate: Replace users of timespec64_trunc
Update the inode timestamp updates to use timestamp_truncate()
instead of timespec64_trunc().

The change was mostly generated by the following coccinelle
script.

virtual context
virtual patch

@r1 depends on patch forall@
struct inode *inode;
identifier i_xtime =~ "^i_[acm]time$";
expression e;
@@

inode->i_xtime =
- timespec64_trunc(
+ timestamp_truncate(
...,
- e);
+ inode);

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Jeff Layton <jlayton@kernel.org>
Cc: adrian.hunter@intel.com
Cc: dedekind1@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: hch@lst.de
Cc: jaegeuk@kernel.org
Cc: jlbec@evilplan.org
Cc: richard@nod.at
Cc: tj@kernel.org
Cc: yuchao0@huawei.com
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: linux-mtd@lists.infradead.org
2019-08-30 07:27:17 -07:00
Linus Torvalds
933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Linus Torvalds
e6983afd92 \n
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Merge tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "This contains cleanups of the fsnotify name removal hook and also a
  patch to disable fanotify permission events for 'proc' filesystem"

* tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: get rid of fsnotify_nameremove()
  fsnotify: move fsnotify_nameremove() hook out of d_delete()
  configfs: call fsnotify_rmdir() hook
  debugfs: call fsnotify_{unlink,rmdir}() hooks
  debugfs: simplify __debugfs_remove_file()
  devpts: call fsnotify_unlink() hook
  tracefs: call fsnotify_{unlink,rmdir}() hooks
  rpc_pipefs: call fsnotify_{unlink,rmdir}() hooks
  btrfs: call fsnotify_rmdir() hook
  fsnotify: add empty fsnotify_{unlink,rmdir}() hooks
  fanotify: Disallow permission events for proc filesystem
2019-07-10 20:09:17 -07:00
David Howells
6bc62f2067 vfs: Convert configfs to use the new mount API
Convert the configfs filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Joel Becker <jlbec@evilplan.org>
cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-07-04 22:01:58 -04:00
Amir Goldstein
6146e78c03 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>
2019-06-20 14:47:21 +02:00
Linus Torvalds
2f4c533499 SPDX update for 5.2-rc3, round 1
Here is another set of reviewed patches that adds SPDX tags to different
 kernel files, based on a set of rules that are being used to parse the
 comments to try to determine that the license of the file is
 "GPL-2.0-or-later" or "GPL-2.0-only".  Only the "obvious" versions of
 these matches are included here, a number of "non-obvious" variants of
 text have been found but those have been postponed for later review and
 analysis.
 
 There is also a patch in here to add the proper SPDX header to a bunch
 of Kbuild files that we have missed in the past due to new files being
 added and forgetting that Kbuild uses two different file names for
 Makefiles.  This issue was reported by the Kbuild maintainer.
 
 These patches have been out for review on the linux-spdx@vger mailing
 list, and while they were created by automatic tools, they were
 hand-verified by a bunch of different people, all whom names are on the
 patches are reviewers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull yet more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of
  these matches are included here, a number of "non-obvious" variants of
  text have been found but those have been postponed for later review
  and analysis.

  There is also a patch in here to add the proper SPDX header to a bunch
  of Kbuild files that we have missed in the past due to new files being
  added and forgetting that Kbuild uses two different file names for
  Makefiles. This issue was reported by the Kbuild maintainer.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits)
  treewide: Add SPDX license identifier - Kbuild
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201
  ...
2019-05-31 08:34:32 -07:00
Thomas Gleixner
328970de0e 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>
2019-05-30 11:25:18 -07:00
Sahitya Tummala
f6122ed2a4 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: 76ae281f63 ('configfs: fix race between dentry put and lookup')
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-05-28 08:11:58 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
4e785e8d99 configs updates for Linux 5.2:
- a fix for an error path use after free (YueHaibing)
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Merge tag 'configfs-for-5.2' of git://git.infradead.org/users/hch/configfs

Pull configfs update from Christoph Hellwig:

 - a fix for an error path use after free (YueHaibing)

* tag 'configfs-for-5.2' of git://git.infradead.org/users/hch/configfs:
  configfs: fix possible use-after-free in configfs_register_group
2019-05-16 11:46:58 -07:00
YueHaibing
35399f87e2 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: 5cf6a51e60 ("configfs: allow dynamic group creation")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-05-08 08:55:19 +02:00
Gustavo A. R. Silva
0a4c92657f 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>
2019-04-08 18:21:02 -05:00
Mike Christie
cc57c07343 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>
2018-07-17 06:14:07 -07:00
Guenter Roeck
1823342a1f configfs: replace strncpy with memcpy
gcc 8.1.0 complains:

fs/configfs/symlink.c:67:3: warning:
	'strncpy' output truncated before terminating nul copying as many
	bytes from a string as its length
fs/configfs/symlink.c: In function 'configfs_get_link':
fs/configfs/symlink.c:63:13: note: length computed here

Using strncpy() is indeed less than perfect since the length of data to
be copied has already been determined with strlen(). Replace strncpy()
with memcpy() to address the warning and optimize the code a little.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-07-02 07:12:55 -06:00
Bart Van Assche
707c623529 configfs: use kvasprintf() instead of open-coding it
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-06-19 07:08:12 +02:00