-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZOXUDgAKCRCRxhvAZXjc
ogplAQCYXt+zcfs1GMhCUtPFzyyCwNsraMNzVwTdFbMz4R1JuQD9HL82VKyvMwmZ
uo6uGVd9xN6cEy61Lpz9K8dn59uVAQE=
=851o
-----END PGP SIGNATURE-----
Merge tag 'v6.6-vfs.autofs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull autofs fixes from Christian Brauner:
"This fixes a memory leak in autofs reported by syzkaller and a missing
conversion from uninterruptible to interruptible wake up when autofs
is in catatonic mode"
* tag 'v6.6-vfs.autofs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
autofs: use wake_up() instead of wake_up_interruptible(()
autofs: fix memory leak of waitqueues in autofs_catatonic_mode
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZOXTKAAKCRCRxhvAZXjc
oifJAQCzi/p+AdQu8LA/0XvR7fTwaq64ZDCibU4BISuLGT2kEgEAuGbuoFZa0rs2
XYD/s4+gi64p9Z01MmXm2XO1pu3GPg0=
=eJz5
-----END PGP SIGNATURE-----
Merge tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs timestamp updates from Christian Brauner:
"This adds VFS support for multi-grain timestamps and converts tmpfs,
xfs, ext4, and btrfs to use them. This carries acks from all relevant
filesystems.
The VFS always uses coarse-grained timestamps when updating the ctime
and mtime after a change. This has the benefit of allowing filesystems
to optimize away a lot of metadata updates, down to around 1 per
jiffy, even when a file is under heavy writes.
Unfortunately, this has always been an issue when we're exporting via
NFSv3, which relies on timestamps to validate caches. A lot of changes
can happen in a jiffy, so timestamps aren't sufficient to help the
client decide to invalidate the cache.
Even with NFSv4, a lot of exported filesystems don't properly support
a change attribute and are subject to the same problems with timestamp
granularity. Other applications have similar issues with timestamps
(e.g., backup applications).
If we were to always use fine-grained timestamps, that would improve
the situation, but that becomes rather expensive, as the underlying
filesystem would have to log a lot more metadata updates.
This introduces fine-grained timestamps that are used when they are
actively queried.
This uses the 31st bit of the ctime tv_nsec field to indicate that
something has queried the inode for the mtime or ctime. When this flag
is set, on the next mtime or ctime update, the kernel will fetch a
fine-grained timestamp instead of the usual coarse-grained one.
As POSIX generally mandates that when the mtime changes, the ctime
must also change the kernel always stores normalized ctime values, so
only the first 30 bits of the tv_nsec field are ever used.
Filesytems can opt into this behavior by setting the FS_MGTIME flag in
the fstype. Filesystems that don't set this flag will continue to use
coarse-grained timestamps.
Various preparatory changes, fixes and cleanups are included:
- Fixup all relevant places where POSIX requires updating ctime
together with mtime. This is a wide-range of places and all
maintainers provided necessary Acks.
- Add new accessors for inode->i_ctime directly and change all
callers to rely on them. Plain accesses to inode->i_ctime are now
gone and it is accordingly rename to inode->__i_ctime and commented
as requiring accessors.
- Extend generic_fillattr() to pass in a request mask mirroring in a
sense the statx() uapi. This allows callers to pass in a request
mask to only get a subset of attributes filled in.
- Rework timestamp updates so it's possible to drop the @now
parameter the update_time() inode operation and associated helpers.
- Add inode_update_timestamps() and convert all filesystems to it
removing a bunch of open-coding"
* tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (107 commits)
btrfs: convert to multigrain timestamps
ext4: switch to multigrain timestamps
xfs: switch to multigrain timestamps
tmpfs: add support for multigrain timestamps
fs: add infrastructure for multigrain timestamps
fs: drop the timespec64 argument from update_time
xfs: have xfs_vn_update_time gets its own timestamp
fat: make fat_update_time get its own timestamp
fat: remove i_version handling from fat_update_time
ubifs: have ubifs_update_time use inode_update_timestamps
btrfs: have it use inode_update_timestamps
fs: drop the timespec64 arg from generic_update_time
fs: pass the request_mask to generic_fillattr
fs: remove silly warning from current_time
gfs2: fix timestamp handling on quota inodes
fs: rename i_ctime field to __i_ctime
selinux: convert to ctime accessor functions
security: convert to ctime accessor functions
apparmor: convert to ctime accessor functions
sunrpc: convert to ctime accessor functions
...
In autofs_wait_release() wake_up() is used to wake up processes waiting
on a mount callback to complete which matches the wait_event_killable()
in autofs_wait().
But in autofs_catatonic_mode() the wake_up_interruptible() was not also
changed at the time autofs_wait_release() was changed.
Signed-off-by: Ian Kent <raven@themaw.net>
Message-Id: <169112719813.7590.4971499386839952992.stgit@donald.themaw.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Syzkaller reports a memory leak:
BUG: memory leak
unreferenced object 0xffff88810b279e00 (size 96):
comm "syz-executor399", pid 3631, jiffies 4294964921 (age 23.870s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 08 9e 27 0b 81 88 ff ff ..........'.....
08 9e 27 0b 81 88 ff ff 00 00 00 00 00 00 00 00 ..'.............
backtrace:
[<ffffffff814cfc90>] kmalloc_trace+0x20/0x90 mm/slab_common.c:1046
[<ffffffff81bb75ca>] kmalloc include/linux/slab.h:576 [inline]
[<ffffffff81bb75ca>] autofs_wait+0x3fa/0x9a0 fs/autofs/waitq.c:378
[<ffffffff81bb88a7>] autofs_do_expire_multi+0xa7/0x3e0 fs/autofs/expire.c:593
[<ffffffff81bb8c33>] autofs_expire_multi+0x53/0x80 fs/autofs/expire.c:619
[<ffffffff81bb6972>] autofs_root_ioctl_unlocked+0x322/0x3b0 fs/autofs/root.c:897
[<ffffffff81bb6a95>] autofs_root_ioctl+0x25/0x30 fs/autofs/root.c:910
[<ffffffff81602a9c>] vfs_ioctl fs/ioctl.c:51 [inline]
[<ffffffff81602a9c>] __do_sys_ioctl fs/ioctl.c:870 [inline]
[<ffffffff81602a9c>] __se_sys_ioctl fs/ioctl.c:856 [inline]
[<ffffffff81602a9c>] __x64_sys_ioctl+0xfc/0x140 fs/ioctl.c:856
[<ffffffff84608225>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff84608225>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84800087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
autofs_wait_queue structs should be freed if their wait_ctr becomes zero.
Otherwise they will be lost.
In this case an AUTOFS_IOC_EXPIRE_MULTI ioctl is done, then a new
waitqueue struct is allocated in autofs_wait(), its initial wait_ctr
equals 2. After that wait_event_killable() is interrupted (it returns
-ERESTARTSYS), so that 'wq->name.name == NULL' condition may be not
satisfied. Actually, this condition can be satisfied when
autofs_wait_release() or autofs_catatonic_mode() is called and, what is
also important, wait_ctr is decremented in those places. Upon the exit of
autofs_wait(), wait_ctr is decremented to 1. Then the unmounting process
begins: kill_sb calls autofs_catatonic_mode(), which should have freed the
waitqueues, but it only decrements its usage counter to zero which is not
a correct behaviour.
edit:imk
This description is of course not correct. The umount performed as a result
of an expire is a umount of a mount that has been automounted, it's not the
autofs mount itself. They happen independently, usually after everything
mounted within the autofs file system has been expired away. If everything
hasn't been expired away the automount daemon can still exit leaving mounts
in place. But expires done in both cases will result in a notification that
calls autofs_wait_release() with a result status. The problem case is the
summary execution of of the automount daemon. In this case any waiting
processes won't be woken up until either they are terminated or the mount
is umounted.
end edit: imk
So in catatonic mode we should free waitqueues which counter becomes zero.
edit: imk
Initially I was concerned that the calling of autofs_wait_release() and
autofs_catatonic_mode() was not mutually exclusive but that can't be the
case (obviously) because the queue entry (or entries) is removed from the
list when either of these two functions are called. Consequently the wait
entry will be freed by only one of these functions or by the woken process
in autofs_wait() depending on the order of the calls.
end edit: imk
Reported-by: syzbot+5e53f70e69ff0c0a1c0c@syzkaller.appspotmail.com
Suggested-by: Takeshi Misawa <jeliantsurux@gmail.com>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: autofs@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Message-Id: <169112719161.7590.6700123246297365841.stgit@donald.themaw.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Commit a2225d931f ("autofs: remove left-over autofs4 stubs")
promised the removal of the fs/autofs/Kconfig fragment for AUTOFS4_FS
within a couple of releases, but five years later this still has not
happened yet, and AUTOFS4_FS is still enabled in 63 defconfigs.
Get rid of it mechanically:
git grep -l CONFIG_AUTOFS4_FS -- '*defconfig' |
xargs sed -i 's/AUTOFS4_FS/AUTOFS_FS/'
Also just remove the AUTOFS4_FS config option stub. Anybody who hasn't
regenerated their config file in the last five years will need to just
get the new name right when they do.
Signed-off-by: Sven Joachim <svenjoac@gmx.de>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.
Reviewed-by: Ian Kent <raven@themaw.net>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-24-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
When adding entries to a directory, POSIX generally requires that the
ctime also be updated alongside the mtime.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Ian Kent <raven@themaw.net>
Message-Id: <20230612104524.17058-4-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("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>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("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>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("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>
Remove the unused inode field of the autofs dentry info structure.
Link: https://lkml.kernel.org/r/165724460393.30914.6511330213821246793.stgit@donald.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The function autofs_mountpoint_changed() is unusual, add a comment about
two cases for which it is needed.
Link: https://lkml.kernel.org/r/165724459804.30914.10974834416046555127.stgit@donald.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The dentry info. field count is used to check if a dentry is in use
during expire. But, to be used for this the count field must account for
the presence of child dentries in a directory dentry.
Therefore it can also be used to check for an empty directory dentry which
can be done without having to to take an additional lock or account for
the presence of a readdir cursor dentry as is done by simple_empty().
Link: https://lkml.kernel.org/r/165724459238.30914.1504611159945950108.stgit@donald.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If an autofs dentry is a mount root directory there's no ->mkdir() call to
set its count to one.
To make the dentry info count consistent for all autofs dentries set count
to one when the dentry info struct is allocated.
Link: https://lkml.kernel.org/r/165724458671.30914.2902424437132835325.stgit@donald.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There's a mistake in commit 2be7828c9f ("get rid of autofs_getpath()")
that affects kernels from v5.13.0, basically missed because of me not
fully testing the change for Al.
The problem is that the hash calculation for the wait name qstr hasn't
been updated to account for the change to use dentry_path_raw(). This
prevents the correct matching an existing wait resulting in multiple
notifications being sent to the daemon for the same mount which must
not occur.
The problem wasn't discovered earlier because it only occurs when
multiple processes trigger a request for the same mount concurrently
so it only shows up in more aggressive testing.
Fixes: 2be7828c9f ("get rid of autofs_getpath()")
Cc: stable@vger.kernel.org
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
allow wq->name.name to point not at the beginning of the object containing
the string, with wq->offset telling how far into it we are. Then we can
bloody well just use dentry_path_raw() instead of autofs_getpath() -
the only real difference is that dentry_path_raw() puts the result into
the end of buffer and returns where it starts.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
The table of ioctl functions should be marked const in order to put them
in read-only memory, and we should use array_index_nospec() to avoid
speculation disclosing the contents of kernel memory to userspace.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ian Kent <raven@themaw.net>
Link: https://lkml.kernel.org/r/20200818122203.GO17456@casper.infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
autofs got broken in some configurations by commit 13c164b1a1
("autofs: switch to kernel_write") because there is now an extra LSM
permission check done by security_file_permission() in rw_verify_area().
autofs is one if the few places that really does want the much more
limited __kernel_write(), because the write is an internal kernel one
that shouldn't do any user permission checks (it also doesn't need the
file_start_write/file_end_write logic, since it's just a pipe).
There are a couple of other cases like that - accounting, core dumping,
and splice - but autofs stands out because it can be built as a module.
As a result, we need to export this internal __kernel_write() function
again.
We really don't want any other module to use this, but we don't have a
"EXPORT_SYMBOL_FOR_AUTOFS_ONLY()". But we can mark it GPL-only to at
least approximate that "internal use only" for licensing.
While in this area, make autofs pass in NULL for the file position
pointer, since it's always a pipe, and we now use a NULL file pointer
for streaming file descriptors (see file_ppos() and commit 438ab720c6:
"vfs: pass ppos=NULL to .read()/.write() of FMODE_STREAM files")
This effectively reverts commits 9db9775224 ("fs: unexport
__kernel_write") and 13c164b1a1 ("autofs: switch to kernel_write").
Fixes: 13c164b1a1 ("autofs: switch to kernel_write")
Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Drop duplicated words {the, at} in comments.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ian Kent <raven@themaw.net>
Link: http://lkml.kernel.org/r/20200811021817.24982-1-rdunlap@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While pipes don't really need sb_writers projection, __kernel_write is an
interface better kept private, and the additional rw_verify_area does not
hurt here.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ian Kent <raven@themaw.net>
New LOOKUP flag, telling path_lookupat() to act as path_mountpointat().
IOW, traverse mounts at the final point and skip revalidation of the
location where it ends up.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull autofs updates from Al Viro:
"autofs misuses checks for ->d_subdirs emptiness; the cursors are in
the same lists, resulting in false negatives. It's not needed anyway,
since autofs maintains counter in struct autofs_info, containing 0 for
removed ones, 1 for live symlinks and 1 + number of children for live
directories, which is precisely what we need for those checks.
This series switches to use of that counter and untangles the crap
around its uses (it needs not be atomic and there's a bunch of
completely pointless "defensive" checks).
This fell out of dcache_readdir work; the main point is to get rid of
->d_subdirs abuses in there. I've more followup cleanups, but I hadn't
run those by Ian yet, so they can go next cycle"
* 'next.autofs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
autofs: don't bother with atomics for ino->count
autofs_dir_rmdir(): check ino->count for deciding whether it's empty...
autofs: get rid of pointless checks around ->count handling
autofs_clear_leaf_automount_flags(): use ino->count instead of ->d_subdirs
if the second call of should_expire() in there ends up
grabbing and returning a new reference to dentry, we need
to drop it before continuing.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All writers are serialized on inode->i_rwsem. So are the readers
outside of expire.c. And the readers in expire.c are in the
code that really doesn't care about narrow races - it's looking
for expiry candidates and its callers have to cope with the
possibility of a good candidate becoming busy right under them.
No point bothering with atomic operations - just use int and
mark the non-serialized readers with READ_ONCE().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* IS_ROOT can't be true for unlink or rmdir victim
* any positive autofs dentry has non-NULL autofs_dentry_ino()
* autofs symlink can't have ->count other than 1
* autofs empty directory can't have ->count other than 1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We want to find out if the parent will become empty after we remove
the victim of rmdir(). Checking if the victim is the only element
of parent's ->d_subdirs is completely wrong - e.g. opening the parent
will end up with a cursor added to its ->d_parent and fooling the
check.
We do maintain ino->count - 0 for anything removed, 1 + number of
children for anything live. Which gives us precisely what we need
for that check...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
autofs_add_active() is always called only once (and on a dentry
with freshly allocated ino, at that). autofs_del_active() is
never called more than once.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* new helper: positive_after(parent, child); parent->d_lock is
held by caller, grabs and returns the first thing after child
in the list of children that has simple_positive() true. NULL
if nothing's found; NULL child == search the entire list.
* get_next_positive_subdir() loses the redundant check for
d_count and switches to use of that helper. BTW, dput(NULL) is
a no-op for a good reason...
* get_next_positive_dentry() switched to the same helper. Logics:
look for positive child in prev; if not found, look for the
positive child of prev's parent following prev, etc. That way
we are guaranteed that we are only moving rootwards through the
ancestors of prev, which is pinned and thus not going anywhere.
Since ->d_parent on autofs never changes, the same goes for
the entire chain of ancestors and we don't need overlapping
->d_lock on them. Which avoids the trylock loops, in addition
to simplifying the logics in there...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Based on 1 normalized pattern(s):
this file is part of the linux kernel and is made available under
the terms of the gnu general public license version 2 or at your
option any later version incorporated herein by reference
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 18 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: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520075211.321157221@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
autofs_d_release() can overlap with lockless ->d_manage(),
ending up with autofs_dentry_ino() freed under the latter.
Make freeing autofs_info instances RCU-delayed...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
autofs does not expect the pipe it is given to have O_NONBLOCK set -
specifically if __kernel_write() in autofs_write() returns -EAGAIN, this
is treated as a fatal error and the pipe is closed.
For safety autofs should, therefore, clear the O_NONBLOCK flag.
Releases of systemd prior to 8th February 2019 used
pipe2(p, O_NONBLOCK|O_CLOEXEC)
and thus (inadvertently) set this flag.
Link: http://lkml.kernel.org/r/154993550902.3321.1183632970046073478.stgit@pluto-themaw-net
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix checkpatch.sh WARNING about the use of seq_printf() to print simple
strings in autofs_show_options(), use seq_puts() in this case.
Link: http://lkml.kernel.org/r/154889012613.4863.12231175554744203482.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an autofs file system mount option that can be used to provide a
generic indicator to applications that the mount entry should be ignored
when displaying mount information.
In other OSes that provide autofs and that provide a mount list to user
space based on the kernel mount list a no-op mount option ("ignore" is
the one use on the most common OS) is allowed so that autofs file system
users can optionally use it.
The idea is that it be used by user space programs to exclude autofs
mounts from consideration when reading the mounts list.
Prior to the change to link /etc/mtab to /proc/self/mounts all I needed
to do to achieve this was to use mount(2) and not update the mtab but
now that no longer works.
I know the symlinking happened a long time ago and I considered doing
this then but, at the time I couldn't remember the commonly used option
name and thought persuading the various utility maintainers would be too
hard.
But now I have a RHEL request to do this for compatibility for a widely
used product so I want to go ahead with it and try and enlist the help
of some utility package maintainers.
Clearly, without the option nothing can be done so it's at least a
start.
Link: http://lkml.kernel.org/r/154725123970.11260.6113771566924907275.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In autofs_fill_super() on error of get inode/make root dentry the return
should be ENOMEM as this is the only failure case of the called
functions.
Link: http://lkml.kernel.org/r/154725123240.11260.796773942606871359.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
autofs_expire_run() calls dput(dentry) to drop the reference count of
dentry. However, dentry is read via autofs_dentry_ino(dentry) after
that. This may result in a use-free-bug. The patch drops the reference
count of dentry only when it is never used.
Link: http://lkml.kernel.org/r/154725122396.11260.16053424107144453867.stgit@pluto-themaw-net
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 092a53452b ("autofs: take more care to not update last_used on
path walk") helped to (partially) resolve a problem where automounts
were not expiring due to aggressive accesses from user space.
This patch was later reverted because, for very large environments, it
meant more mount requests from clients and when there are a lot of
clients this caused a fairly significant increase in server load.
But there is a need for both types of expire check, depending on use
case, so add a mount option to allow for strict update of last use of
autofs dentrys (which just means not updating the last use on path walk
access).
Link: http://lkml.kernel.org/r/154296973880.9889.14085372741514507967.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the superblock info. catatonic setting to be part of a flags bit
field.
Link: http://lkml.kernel.org/r/154296973142.9889.17275721668508589639.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The parse_options() function uses a long list of parameters, most of
which are present in the super block info structure already.
The mount parameters set in parse_options() options don't require
cleanup so using the super block info struct directly is simpler.
Link: http://lkml.kernel.org/r/154296972423.9889.9368859245676473329.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Al Viro made some suggestions to improve the implementation of commit
0633da48f0 ("fix autofs_sbi() does not check super block type").
The check is unnecessary in all cases except for ioctl usage so placing
the check in the super block accessor function adds a small overhead to
the common case where it isn't needed.
So it's sufficient to do this in the ioctl code only.
Also the check in the ioctl code is needlessly complex.
[akpm@linux-foundation.org: declare autofs_fs_type in .h, not .c]
Link: http://lkml.kernel.org/r/154296970987.9889.1597442413573683096.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge more updates from Andrew Morton:
- the rest of MM
- procfs updates
- various misc things
- more y2038 fixes
- get_maintainer updates
- lib/ updates
- checkpatch updates
- various epoll updates
- autofs updates
- hfsplus
- some reiserfs work
- fatfs updates
- signal.c cleanups
- ipc/ updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits)
ipc/util.c: update return value of ipc_getref from int to bool
ipc/util.c: further variable name cleanups
ipc: simplify ipc initialization
ipc: get rid of ids->tables_initialized hack
lib/rhashtable: guarantee initial hashtable allocation
lib/rhashtable: simplify bucket_table_alloc()
ipc: drop ipc_lock()
ipc/util.c: correct comment in ipc_obtain_object_check
ipc: rename ipcctl_pre_down_nolock()
ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid()
ipc: reorganize initialization of kern_ipc_perm.seq
ipc: compute kern_ipc_perm.id under the ipc lock
init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE
fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp
adfs: use timespec64 for time conversion
kernel/sysctl.c: fix typos in comments
drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md
fork: don't copy inconsistent signal handler state to child
signal: make get_signal() return bool
signal: make sigkill_pending() return bool
...
The userspace automount(8) daemon is meant to perform a forced expire when
sent a SIGUSR2.
But since the expiration is routed through the kernel and the kernel
doesn't send an expire request if the mount is busy this hasn't worked at
least since autofs version 5.
Add an AUTOFS_EXP_FORCED flag to allow implemention of the feature and
bump the protocol version so user space can check if it's implemented if
needed.
Link: http://lkml.kernel.org/r/152937734715.21213.6594007182776598970.stgit@pluto.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the usage of the expire flags consistent by naming the expire flags
the same as it is named in the version 5 miscelaneous ioctl parameters and
only check the bit flags when needed.
Link: http://lkml.kernel.org/r/152937734046.21213.9454131988766280028.stgit@pluto.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
