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2023-02-21Merge tag 'for-6.3/dio-2023-02-16' of git://git.kernel.dk/linuxLinus Torvalds1-0/+24
Pull legacy dio update from Jens Axboe: "We only have a few file systems that use the old dio code, make them select it rather than build it unconditionally" * tag 'for-6.3/dio-2023-02-16' of git://git.kernel.dk/linux: fs: build the legacy direct I/O code conditionally fs: move sb_init_dio_done_wq out of direct-io.c
2023-02-20Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linuxLinus Torvalds1-1/+0
Pull fscrypt updates from Eric Biggers: "Simplify the implementation of the test_dummy_encryption mount option by adding the 'test dummy key' on-demand" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: fscrypt: clean up fscrypt_add_test_dummy_key() fs/super.c: stop calling fscrypt_destroy_keyring() from __put_super() f2fs: stop calling fscrypt_add_test_dummy_key() ext4: stop calling fscrypt_add_test_dummy_key() fscrypt: add the test dummy encryption key on-demand
2023-02-08fs/super.c: stop calling fscrypt_destroy_keyring() from __put_super()Eric Biggers1-1/+0
Now that the key associated with the "test_dummy_operation" mount option is added on-demand when it's needed, rather than immediately when the filesystem is mounted, fscrypt_destroy_keyring() no longer needs to be called from __put_super() to avoid a memory leak on mount failure. Remove this call, which was causing confusion because it appeared to be a sleep-in-atomic bug (though it wasn't, for a somewhat-subtle reason). Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20230208062107.199831-5-ebiggers@kernel.org
2023-01-27fs: Use CHECK_DATA_CORRUPTION() when kernel bugs are detectedJann Horn1-4/+17
Currently, filp_close() and generic_shutdown_super() use printk() to log messages when bugs are detected. This is problematic because infrastructure like syzkaller has no idea that this message indicates a bug. In addition, some people explicitly want their kernels to BUG() when kernel data corruption has been detected (CONFIG_BUG_ON_DATA_CORRUPTION). And finally, when generic_shutdown_super() detects remaining inodes on a system without CONFIG_BUG_ON_DATA_CORRUPTION, it would be nice if later accesses to a busy inode would at least crash somewhat cleanly rather than walking through freed memory. To address all three, use CHECK_DATA_CORRUPTION() when kernel bugs are detected. Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-26fs: move sb_init_dio_done_wq out of direct-io.cChristoph Hellwig1-0/+24
sb_init_dio_done_wq is also used by the iomap code, so move it to super.c in preparation for building direct-io.c conditionally. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230125065839.191256-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-12-13Merge tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds1-51/+9
Pull misc vfs updates from Al Viro: "misc pile" * tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: sysv: Fix sysv_nblocks() returns wrong value get rid of INT_LIMIT, use type_max() instead btrfs: replace INT_LIMIT(loff_t) with OFFSET_MAX fs: simplify vfs_get_super fs: drop useless condition from inode_needs_update_time
2022-11-25fs: simplify vfs_get_superChristoph Hellwig1-51/+9
Remove the pointless keying argument and associated enum and pass the fill_super callback and a "bool reconf" instead. Also mark the function static given that there are no users outside of super.c. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-10-20fscrypt: fix keyring memory leak on mount failureEric Biggers1-1/+2
Commit d7e7b9af104c ("fscrypt: stop using keyrings subsystem for fscrypt_master_key") moved the keyring destruction from __put_super() to generic_shutdown_super() so that the filesystem's block device(s) are still available. Unfortunately, this causes a memory leak in the case where a mount is attempted with the test_dummy_encryption mount option, but the mount fails after the option has already been processed. To fix this, attempt the keyring destruction in both places. Reported-by: syzbot+104c2a89561289cec13e@syzkaller.appspotmail.com Fixes: d7e7b9af104c ("fscrypt: stop using keyrings subsystem for fscrypt_master_key") Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Link: https://lore.kernel.org/r/20221011213838.209879-1-ebiggers@kernel.org
2022-09-22fscrypt: stop using keyrings subsystem for fscrypt_master_keyEric Biggers1-1/+1
The approach of fs/crypto/ internally managing the fscrypt_master_key structs as the payloads of "struct key" objects contained in a "struct key" keyring has outlived its usefulness. The original idea was to simplify the code by reusing code from the keyrings subsystem. However, several issues have arisen that can't easily be resolved: - When a master key struct is destroyed, blk_crypto_evict_key() must be called on any per-mode keys embedded in it. (This started being the case when inline encryption support was added.) Yet, the keyrings subsystem can arbitrarily delay the destruction of keys, even past the time the filesystem was unmounted. Therefore, currently there is no easy way to call blk_crypto_evict_key() when a master key is destroyed. Currently, this is worked around by holding an extra reference to the filesystem's request_queue(s). But it was overlooked that the request_queue reference is *not* guaranteed to pin the corresponding blk_crypto_profile too; for device-mapper devices that support inline crypto, it doesn't. This can cause a use-after-free. - When the last inode that was using an incompletely-removed master key is evicted, the master key removal is completed by removing the key struct from the keyring. Currently this is done via key_invalidate(). Yet, key_invalidate() takes the key semaphore. This can deadlock when called from the shrinker, since in fscrypt_ioctl_add_key(), memory is allocated with GFP_KERNEL under the same semaphore. - More generally, the fact that the keyrings subsystem can arbitrarily delay the destruction of keys (via garbage collection delay, or via random processes getting temporary key references) is undesirable, as it means we can't strictly guarantee that all secrets are ever wiped. - Doing the master key lookups via the keyrings subsystem results in the key_permission LSM hook being called. fscrypt doesn't want this, as all access control for encrypted files is designed to happen via the files themselves, like any other files. The workaround which SELinux users are using is to change their SELinux policy to grant key search access to all domains. This works, but it is an odd extra step that shouldn't really have to be done. The fix for all these issues is to change the implementation to what I should have done originally: don't use the keyrings subsystem to keep track of the filesystem's fscrypt_master_key structs. Instead, just store them in a regular kernel data structure, and rework the reference counting, locking, and lifetime accordingly. Retain support for RCU-mode key lookups by using a hash table. Replace fscrypt_sb_free() with fscrypt_sb_delete(), which releases the keys synchronously and runs a bit earlier during unmount, so that block devices are still available. A side effect of this patch is that neither the master keys themselves nor the filesystem keyrings will be listed in /proc/keys anymore. ("Master key users" and the master key users keyrings will still be listed.) However, this was mostly an implementation detail, and it was intended just for debugging purposes. I don't know of anyone using it. This patch does *not* change how "master key users" (->mk_users) works; that still uses the keyrings subsystem. That is still needed for key quotas, and changing that isn't necessary to solve the issues listed above. If we decide to change that too, it would be a separate patch. I've marked this as fixing the original commit that added the fscrypt keyring, but as noted above the most important issue that this patch fixes wasn't introduced until the addition of inline encryption support. Fixes: 22d94f493bfb ("fscrypt: add FS_IOC_ADD_ENCRYPTION_KEY ioctl") Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20220901193208.138056-2-ebiggers@kernel.org
2022-08-08Merge tag 'fuse-update-6.0' of ↵Linus Torvalds1-2/+31
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Fix an issue with reusing the bdi in case of block based filesystems - Allow root (in init namespace) to access fuse filesystems in user namespaces if expicitly enabled with a module param - Misc fixes * tag 'fuse-update-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: retire block-device-based superblock on force unmount vfs: function to prevent re-use of block-device-based superblocks virtio_fs: Modify format for virtio_fs_direct_access virtiofs: delete unused parameter for virtio_fs_cleanup_vqs fuse: Add module param for CAP_SYS_ADMIN access bypassing allow_other fuse: Remove the control interface for virtio-fs fuse: ioctl: translate ENOSYS fuse: limit nsec fuse: avoid unnecessary spinlock bump fuse: fix deadlock between atomic O_TRUNC and page invalidation fuse: write inode in fuse_release()
2022-07-27vfs: function to prevent re-use of block-device-based superblocksDaniil Lunev1-2/+31
The function is to be called from filesystem-specific code to mark a superblock to be ignored by superblock test and thus never re-used. The function also unregisters bdi if the bdi is per-superblock to avoid collision if a new superblock is created to represent the filesystem. generic_shutdown_super() skips unregistering bdi for a retired superlock as it assumes retire function has already done it. This patch adds the functionality only for the block-device-based supers, since the primary use case of the feature is to gracefully handle force unmount of external devices, mounted with FUSE. This can be further extended to cover all superblocks, if the need arises. Signed-off-by: Daniil Lunev <dlunev@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-07-04mm: shrinkers: provide shrinkers with namesRoman Gushchin1-1/+5
Currently shrinkers are anonymous objects. For debugging purposes they can be identified by count/scan function names, but it's not always useful: e.g. for superblock's shrinkers it's nice to have at least an idea of to which superblock the shrinker belongs. This commit adds names to shrinkers. register_shrinker() and prealloc_shrinker() functions are extended to take a format and arguments to master a name. In some cases it's not possible to determine a good name at the time when a shrinker is allocated. For such cases shrinker_debugfs_rename() is provided. The expected format is: <subsystem>-<shrinker_type>[:<instance>]-<id> For some shrinkers an instance can be encoded as (MAJOR:MINOR) pair. After this change the shrinker debugfs directory looks like: $ cd /sys/kernel/debug/shrinker/ $ ls dquota-cache-16 sb-devpts-28 sb-proc-47 sb-tmpfs-42 mm-shadow-18 sb-devtmpfs-5 sb-proc-48 sb-tmpfs-43 mm-zspool:zram0-34 sb-hugetlbfs-17 sb-pstore-31 sb-tmpfs-44 rcu-kfree-0 sb-hugetlbfs-33 sb-rootfs-2 sb-tmpfs-49 sb-aio-20 sb-iomem-12 sb-securityfs-6 sb-tracefs-13 sb-anon_inodefs-15 sb-mqueue-21 sb-selinuxfs-22 sb-xfs:vda1-36 sb-bdev-3 sb-nsfs-4 sb-sockfs-8 sb-zsmalloc-19 sb-bpf-32 sb-pipefs-14 sb-sysfs-26 thp-deferred_split-10 sb-btrfs:vda2-24 sb-proc-25 sb-tmpfs-1 thp-zero-9 sb-cgroup2-30 sb-proc-39 sb-tmpfs-27 xfs-buf:vda1-37 sb-configfs-23 sb-proc-41 sb-tmpfs-29 xfs-inodegc:vda1-38 sb-dax-11 sb-proc-45 sb-tmpfs-35 sb-debugfs-7 sb-proc-46 sb-tmpfs-40 [roman.gushchin@linux.dev: fix build warnings] Link: https://lkml.kernel.org/r/Yr+ZTnLb9lJk6fJO@castle Reported-by: kernel test robot <lkp@intel.com> Link: https://lkml.kernel.org/r/20220601032227.4076670-4-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Dave Chinner <dchinner@redhat.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-18block: add a bdev_stable_writes helperChristoph Hellwig1-1/+1
Add a helper to check the stable writes flag based on the block_device instead of having to poke into the block layer internal request_queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220415045258.199825-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-30vfs: make freeze_super abort when sync_filesystem returns errorDarrick J. Wong1-7/+12
If we fail to synchronize the filesystem while preparing to freeze the fs, abort the freeze. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian Brauner <brauner@kernel.org>
2022-01-22mm: remove cleancacheChristoph Hellwig1-3/+0
Patch series "remove Xen tmem leftovers". Since the removal of the Xen tmem driver in 2019, the cleancache hooks are entirely unused, as are large parts of frontswap. This series against linux-next (with the folio changes included) removes cleancaches, and cuts down frontswap to the bits actually used by zswap. This patch (of 13): The cleancache subsystem is unused since the removal of Xen tmem driver in commit 814bbf49dcd0 ("xen: remove tmem driver"). [akpm@linux-foundation.org: remove now-unreachable code] Link: https://lkml.kernel.org/r/20211224062246.1258487-1-hch@lst.de Link: https://lkml.kernel.org/r/20211224062246.1258487-2-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Vitaly Wool <vitaly.wool@konsulko.com> 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>
2022-01-17devtmpfs regression fix: reconfigure on each mountNeilBrown1-2/+2
Prior to Linux v5.4 devtmpfs used mount_single() which treats the given mount options as "remount" options, so it updates the configuration of the single super_block on each mount. Since that was changed, the mount options used for devtmpfs are ignored. This is a regression which affect systemd - which mounts devtmpfs with "-o mode=755,size=4m,nr_inodes=1m". This patch restores the "remount" effect by calling reconfigure_single() Fixes: d401727ea0d7 ("devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()") Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06fs: explicitly unregister per-superblock BDIsChristoph Hellwig1-0/+3
Add a new SB_I_ flag to mark superblocks that have an ephemeral bdi associated with them, and unregister it when the superblock is shut down. Link: https://lkml.kernel.org/r/20211021124441.668816-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Richard Weinberger <richard@nod.at> Cc: Vignesh Raghavendra <vigneshr@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-08-09block: remove the bd_bdi in struct block_deviceChristoph Hellwig1-1/+1
Just retrieve the bdi from the disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01block: move bd_mutex to struct gendiskChristoph Hellwig1-4/+4
Replace the per-block device bd_mutex with a per-gendisk open_mutex, thus simplifying locking wherever we deal with partitions. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Link: https://lore.kernel.org/r/20210525061301.2242282-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-22fs,security: Add sb_delete hookMickaël Salaün1-0/+1
The sb_delete security hook is called when shutting down a superblock, which may be useful to release kernel objects tied to the superblock's lifetime (e.g. inodes). This new hook is needed by Landlock to release (ephemerally) tagged struct inodes. This comes from the unprivileged nature of Landlock described in the next commit. Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: James Morris <jmorris@namei.org> Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com> Reviewed-by: Jann Horn <jannh@google.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210422154123.13086-7-mic@digikod.net Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2021-02-22Merge tag 'docs-5.12' of git://git.lwn.net/linuxLinus Torvalds1-6/+6
Pull documentation updates from Jonathan Corbet: "It has been a relatively quiet cycle in docsland. - As promised, the minimum Sphinx version to build the docs is now 1.7, and we have dropped support for Python 2 entirely. That allowed the removal of a bunch of compatibility code. - A set of treewide warning fixups from Mauro that I applied after it became clear nobody else was going to deal with them. - The automarkup mechanism can now create cross-references from relative paths to RST files. - More translations, typo fixes, and warning fixes" * tag 'docs-5.12' of git://git.lwn.net/linux: (75 commits) docs: kernel-hacking: be more civil docs: Remove the Microsoft rhetoric Documentation/admin-guide: kernel-parameters: Update nohlt section doc/admin-guide: fix spelling mistake: "perfomance" -> "performance" docs: Document cross-referencing using relative path docs: Enable usage of relative paths to docs on automarkup docs: thermal: fix spelling mistakes Documentation: admin-guide: Update kvm/xen config option docs: Make syscalls' helpers naming consistent coding-style.rst: Avoid comma statements Documentation: /proc/loadavg: add 3 more field descriptions Documentation/submitting-patches: Add blurb about backtraces in commit messages Docs: drop Python 2 support Move our minimum Sphinx version to 1.7 Documentation: input: define ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams scripts/kernel-doc: add internal hyperlink to DOC: sections Update Documentation/admin-guide/sysctl/fs.rst docs: Update DTB format references docs: zh_CN: add iio index.rst translation docs/zh_CN: add iio ep93xx_adc.rst translation ...
2021-01-25block: remove the NULL bdev check in bdev_read_onlyChristoph Hellwig1-1/+2
Only a single caller can end up in bdev_read_only, so move the check there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-22fs: fix kernel-doc markupsMauro Carvalho Chehab1-6/+6
Two markups are at the wrong place. Kernel-doc only support having the comment just before the identifier. Also, some identifiers have different names between their prototypes and the kernel-doc markup. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/96b1e1b388600ab092331f6c4e88ff8e8779ce6c.1610610937.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-02block: remove i_bdevChristoph Hellwig1-25/+19
Switch the block device lookup interfaces to directly work with a dev_t so that struct block_device references are only acquired by the blkdev_get variants (and the blk-cgroup special case). This means that we now don't need an extra reference in the inode and can generally simplify handling of struct block_device to keep the lookups contained in the core block layer code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Coly Li <colyli@suse.de> [bcache] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-02fs: remove get_super_thawed and get_super_exclusive_thawedChristoph Hellwig1-49/+2
Just open code the wait in the only caller of both functions. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-11vfs: move __sb_{start,end}_write* to fs.hDarrick J. Wong1-30/+0
Now that we've straightened out the callers, move these three functions to fs.h since they're fairly trivial. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz>
2020-11-11vfs: separate __sb_start_write into blocking and non-blocking helpersDarrick J. Wong1-6/+12
Break this function into two helpers so that it's obvious that the trylock versions return a value that must be checked, and the blocking versions don't require that. While we're at it, clean up the return type mismatch. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-11-11vfs: remove lockdep bogosity in __sb_start_writeDarrick J. Wong1-29/+4
__sb_start_write has some weird looking lockdep code that claims to exist to handle nested freeze locking requests from xfs. The code as written seems broken -- if we think we hold a read lock on any of the higher freeze levels (e.g. we hold SB_FREEZE_WRITE and are trying to lock SB_FREEZE_PAGEFAULT), it converts a blocking lock attempt into a trylock. However, it's not correct to downgrade a blocking lock attempt to a trylock unless the downgrading code or the callers are prepared to deal with that situation. Neither __sb_start_write nor its callers handle this at all. For example: sb_start_pagefault ignores the return value completely, with the result that if xfs_filemap_fault loses a race with a different thread trying to fsfreeze, it will proceed without pagefault freeze protection (thereby breaking locking rules) and then unlocks the pagefault freeze lock that it doesn't own on its way out (thereby corrupting the lock state), which leads to a system hang shortly afterwards. Normally, this won't happen because our ownership of a read lock on a higher freeze protection level blocks fsfreeze from grabbing a write lock on that higher level. *However*, if lockdep is offline, lock_is_held_type unconditionally returns 1, which means that percpu_rwsem_is_held returns 1, which means that __sb_start_write unconditionally converts blocking freeze lock attempts into trylocks, even when we *don't* hold anything that would block a fsfreeze. Apparently this all held together until 5.10-rc1, when bugs in lockdep caused lockdep to shut itself off early in an fstests run, and once fstests gets to the "race writes with freezer" tests, kaboom. This might explain the long trail of vanishingly infrequent livelocks in fstests after lockdep goes offline that I've never been able to diagnose. We could fix it by spinning on the trylock if wait==true, but AFAICT the locking works fine if lockdep is not built at all (and I didn't see any complaints running fstests overnight), so remove this snippet entirely. NOTE: Commit f4b554af9931 in 2015 created the current weird logic (which used to exist in a different form in commit 5accdf82ba25c from 2012) in __sb_start_write. XFS solved this whole problem in the late 2.6 era by creating a variant of transactions (XFS_TRANS_NO_WRITECOUNT) that don't grab intwrite freeze protection, thus making lockdep's solution unnecessary. The commit claims that Dave Chinner explained that the trylock hack + comment could be removed, but nobody ever did. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz>
2020-09-24bdi: replace BDI_CAP_STABLE_WRITES with a queue and a sb flagChristoph Hellwig1-0/+2
The BDI_CAP_STABLE_WRITES is one of the few bits of information in the backing_dev_info shared between the block drivers and the writeback code. To help untangling the dependency replace it with a queue flag and a superblock flag derived from it. This also helps with the case of e.g. a file system requiring stable writes due to its own checksumming, but not forcing it on other users of the block device like the swap code. One downside is that we an't support the stable_pages_required bdi attribute in sysfs anymore. It is replaced with a queue attribute which also is writable for easier testing. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11Merge branch 'work.misc' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes from Al Viro: "A couple of trivial patches that fell through the cracks last cycle" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: fix indentation in deactivate_super() vfs: Remove duplicated d_mountpoint check in __is_local_mountpoint
2020-06-03Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-blockLinus Torvalds1-3/+1
Pull block updates from Jens Axboe: "Core block changes that have been queued up for this release: - Remove dead blk-throttle and blk-wbt code (Guoqing) - Include pid in blktrace note traces (Jan) - Don't spew I/O errors on wouldblock termination (me) - Zone append addition (Johannes, Keith, Damien) - IO accounting improvements (Konstantin, Christoph) - blk-mq hardware map update improvements (Ming) - Scheduler dispatch improvement (Salman) - Inline block encryption support (Satya) - Request map fixes and improvements (Weiping) - blk-iocost tweaks (Tejun) - Fix for timeout failing with error injection (Keith) - Queue re-run fixes (Douglas) - CPU hotplug improvements (Christoph) - Queue entry/exit improvements (Christoph) - Move DMA drain handling to the few drivers that use it (Christoph) - Partition handling cleanups (Christoph)" * tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block: (127 commits) block: mark bio_wouldblock_error() bio with BIO_QUIET blk-wbt: rename __wbt_update_limits to wbt_update_limits blk-wbt: remove wbt_update_limits blk-throttle: remove tg_drain_bios blk-throttle: remove blk_throtl_drain null_blk: force complete for timeout request blk-mq: drain I/O when all CPUs in a hctx are offline blk-mq: add blk_mq_all_tag_iter blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx blk-mq: use BLK_MQ_NO_TAG in more places blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG blk-mq: move more request initialization to blk_mq_rq_ctx_init blk-mq: simplify the blk_mq_get_request calling convention blk-mq: remove the bio argument to ->prepare_request nvme: force complete cancelled requests blk-mq: blk-mq: provide forced completion method block: fix a warning when blkdev.h is included for !CONFIG_BLOCK builds block: blk-crypto-fallback: remove redundant initialization of variable err block: reduce part_stat_lock() scope block: use __this_cpu_add() instead of access by smp_processor_id() ...
2020-05-29fs: fix indentation in deactivate_super()Yufen Yu1-1/+1
Fix the breaked indent in deactive_super(). Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-10bdi: remove the name field in struct backing_dev_infoChristoph Hellwig1-2/+0
The name is only printed for a not registered bdi in writeback. Use the device name there as is more useful anyway for the unlike case that the warning triggers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-10bdi: simplify bdi_allocChristoph Hellwig1-1/+1
Merge the _node vs normal version and drop the superflous gfp_t argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-29Fix use after free in get_tree_bdev()David Howells1-1/+1
Commit 6fcf0c72e4b9, a fix to get_tree_bdev() put a missing blkdev_put() in the wrong place, before a warnf() that displays the bdev under consideration rather after it. This results in a silent lockup in printk("%pg") called via warnf() from get_tree_bdev() under some circumstances when there's a race with the blockdev being frozen. This can be caused by xfstests/tests/generic/085 in combination with Lukas Czerner's ext4 mount API conversion patchset. It looks like it ought to occur with other users of get_tree_bdev() such as XFS, but apparently doesn't. Fix this by switching the order of the lines. Fixes: 6fcf0c72e4b9 ("vfs: add missing blkdev_put() in get_tree_bdev()") Reported-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Ian Kent <raven@themaw.net> cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-18fs: call fsnotify_sb_delete after evict_inodesEric Sandeen1-1/+3
When a filesystem is unmounted, we currently call fsnotify_sb_delete() before evict_inodes(), which means that fsnotify_unmount_inodes() must iterate over all inodes on the superblock looking for any inodes with watches. This is inefficient and can lead to livelocks as it iterates over many unwatched inodes. At this point, SB_ACTIVE is gone and dropping refcount to zero kicks the inode out out immediately, so anything processed by fsnotify_sb_delete / fsnotify_unmount_inodes gets evicted in that loop. After that, the call to evict_inodes will evict everything else with a zero refcount. This should speed things up overall, and avoid livelocks in fsnotify_unmount_inodes(). Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-10-10Merge branch 'work.mount3' of ↵Linus Torvalds1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull mount fixes from Al Viro: "A couple of regressions from the mount series" * 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: add missing blkdev_put() in get_tree_bdev() shmem: fix LSM options parsing
2019-10-10vfs: add missing blkdev_put() in get_tree_bdev()Ian Kent1-1/+4
Is there are a couple of missing blkdev_put() in get_tree_bdev()? Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-25Merge tag 'fuse-update-5.4' of ↵Linus Torvalds1-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Continue separating the transport (user/kernel communication) and the filesystem layers of fuse. Getting rid of most layering violations will allow for easier cleanup and optimization later on. - Prepare for the addition of the virtio-fs filesystem. The actual filesystem will be introduced by a separate pull request. - Convert to new mount API. - Various fixes, optimizations and cleanups. * tag 'fuse-update-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (55 commits) fuse: Make fuse_args_to_req static fuse: fix memleak in cuse_channel_open fuse: fix beyond-end-of-page access in fuse_parse_cache() fuse: unexport fuse_put_request fuse: kmemcg account fs data fuse: on 64-bit store time in d_fsdata directly fuse: fix missing unlock_page in fuse_writepage() fuse: reserve byteswapped init opcodes fuse: allow skipping control interface and forced unmount fuse: dissociate DESTROY from fuseblk fuse: delete dentry if timeout is zero fuse: separate fuse device allocation and installation in fuse_conn fuse: add fuse_iqueue_ops callbacks fuse: extract fuse_fill_super_common() fuse: export fuse_dequeue_forget() function fuse: export fuse_get_unique() fuse: export fuse_send_init_request() fuse: export fuse_len_args() fuse: export fuse_end_request() fuse: fix request limit ...
2019-09-19Merge branch 'work.mount2' of ↵Linus Torvalds1-7/+28
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc mount API conversions from Al Viro: "Conversions to new API for shmem and friends and for mount_mtd()-using filesystems. As for the rest of the mount API conversions in -next, some of them belong in the individual trees (e.g. binderfs one should definitely go through android folks, after getting redone on top of their changes). I'm going to drop those and send the rest (trivial ones + stuff ACKed by maintainers) in a separate series - by that point they are independent from each other. Some stuff has already migrated into individual trees (NFS conversion, for example, or FUSE stuff, etc.); those presumably will go through the regular merges from corresponding trees." * 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Make fs_parse() handle fs_param_is_fd-type params better vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API shmem_parse_one(): switch to use of fs_parse() shmem_parse_options(): take handling a single option into a helper shmem_parse_options(): don't bother with mpol in separate variable shmem_parse_options(): use a separate structure to keep the results make shmem_fill_super() static make ramfs_fill_super() static devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single() vfs: Convert squashfs to use the new mount API mtd: Kill mount_mtd() vfs: Convert jffs2 to use the new mount API vfs: Convert cramfs to use the new mount API vfs: Convert romfs to use the new mount API vfs: Add a single-or-reconfig keying to vfs_get_super()
2019-09-19Merge tag 'y2038-vfs' of ↵Linus Torvalds1-0/+2
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
2019-09-19Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscryptLinus Torvalds1-0/+2
Pull fscrypt updates from Eric Biggers: "This is a large update to fs/crypto/ which includes: - Add ioctls that add/remove encryption keys to/from a filesystem-level keyring. These fix user-reported issues where e.g. an encrypted home directory can break NetworkManager, sshd, Docker, etc. because they don't get access to the needed keyring. These ioctls also provide a way to lock encrypted directories that doesn't use the vm.drop_caches sysctl, so is faster, more reliable, and doesn't always need root. - Add a new encryption policy version ("v2") which switches to a more standard, secure, and flexible key derivation function, and starts verifying that the correct key was supplied before using it. The key derivation improvement is needed for its own sake as well as for ongoing feature work for which the current way is too inflexible. Work is in progress to update both Android and the 'fscrypt' userspace tool to use both these features. (Working patches are available and just need to be reviewed+merged.) Chrome OS will likely use them too. This has also been tested on ext4, f2fs, and ubifs with xfstests -- both the existing encryption tests, and the new tests for this. This has also been in linux-next since Aug 16 with no reported issues. I'm also using an fscrypt v2-encrypted home directory on my personal desktop" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt: (27 commits) ext4 crypto: fix to check feature status before get policy fscrypt: document the new ioctls and policy version ubifs: wire up new fscrypt ioctls f2fs: wire up new fscrypt ioctls ext4: wire up new fscrypt ioctls fscrypt: require that key be added when setting a v2 encryption policy fscrypt: add FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS ioctl fscrypt: allow unprivileged users to add/remove keys for v2 policies fscrypt: v2 encryption policy support fscrypt: add an HKDF-SHA512 implementation fscrypt: add FS_IOC_GET_ENCRYPTION_KEY_STATUS ioctl fscrypt: add FS_IOC_REMOVE_ENCRYPTION_KEY ioctl fscrypt: add FS_IOC_ADD_ENCRYPTION_KEY ioctl fscrypt: rename keyinfo.c to keysetup.c fscrypt: move v1 policy key setup to keysetup_v1.c fscrypt: refactor key setup code in preparation for v2 policies fscrypt: rename fscrypt_master_key to fscrypt_direct_key fscrypt: add ->ci_inode to fscrypt_info fscrypt: use FSCRYPT_* definitions, not FS_* fscrypt: use FSCRYPT_ prefix for uapi constants ...
2019-09-06vfs: subtype handling moved to fuseDavid Howells1-5/+0
The unused vfs code can be removed. Don't pass empty subtype (same as if ->parse callback isn't called). The bits that are left involve determining whether it's permitted to split the filesystem type string passed in to mount(2). Consequently, this means that we cannot get rid of the FS_HAS_SUBTYPE flag unless we define that a type string with a dot in it always indicates a subtype specification. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-05vfs: Add a single-or-reconfig keying to vfs_get_super()David Howells1-7/+28
Add an additional keying mode to vfs_get_super() to indicate that only a single superblock should exist in the system, and that, if it does, further mounts should invoke reconfiguration upon it. This allows mount_single() to be replaced. [Fix by Eric Biggers folded in] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-05vfs: Create fs_context-aware mount_bdev() replacementDavid Howells1-0/+94
Create a function, get_tree_bdev(), that is fs_context-aware and a ->get_tree() counterpart of mount_bdev(). It caches the block device pointer in the fs_context struct so that this information can be passed into sget_fc()'s test and set functions. Signed-off-by: David Howells <dhowells@redhat.com> cc: Jens Axboe <axboe@kernel.dk> cc: linux-block@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-05new helper: get_tree_keyed()Al Viro1-0/+10
For vfs_get_keyed_super users. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-08-30vfs: Add file timestamp range supportDeepa Dinamani1-0/+2
Add fields to the superblock to track the min and max timestamps supported by filesystems. Initially, when a superblock is allocated, initialize it to the max and min values the fields can hold. Individual filesystems override these to match their actual limits. Pseudo filesystems are assumed to always support the min and max allowable values for the fields. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Jeff Layton <jlayton@kernel.org>
2019-08-13fscrypt: add FS_IOC_ADD_ENCRYPTION_KEY ioctlEric Biggers1-0/+2
Add a new fscrypt ioctl, FS_IOC_ADD_ENCRYPTION_KEY. This ioctl adds an encryption key to the filesystem's fscrypt keyring ->s_master_keys, making any files encrypted with that key appear "unlocked". Why we need this ~~~~~~~~~~~~~~~~ The main problem is that the "locked/unlocked" (ciphertext/plaintext) status of encrypted files is global, but the fscrypt keys are not. fscrypt only looks for keys in the keyring(s) the process accessing the filesystem is subscribed to: the thread keyring, process keyring, and session keyring, where the session keyring may contain the user keyring. Therefore, userspace has to put fscrypt keys in the keyrings for individual users or sessions. But this means that when a process with a different keyring tries to access encrypted files, whether they appear "unlocked" or not is nondeterministic. This is because it depends on whether the files are currently present in the inode cache. Fixing this by consistently providing each process its own view of the filesystem depending on whether it has the key or not isn't feasible due to how the VFS caches work. Furthermore, while sometimes users expect this behavior, it is misguided for two reasons. First, it would be an OS-level access control mechanism largely redundant with existing access control mechanisms such as UNIX file permissions, ACLs, LSMs, etc. Encryption is actually for protecting the data at rest. Second, almost all users of fscrypt actually do need the keys to be global. The largest users of fscrypt, Android and Chromium OS, achieve this by having PID 1 create a "session keyring" that is inherited by every process. This works, but it isn't scalable because it prevents session keyrings from being used for any other purpose. On general-purpose Linux distros, the 'fscrypt' userspace tool [1] can't similarly abuse the session keyring, so to make 'sudo' work on all systems it has to link all the user keyrings into root's user keyring [2]. This is ugly and raises security concerns. Moreover it can't make the keys available to system services, such as sshd trying to access the user's '~/.ssh' directory (see [3], [4]) or NetworkManager trying to read certificates from the user's home directory (see [5]); or to Docker containers (see [6], [7]). By having an API to add a key to the *filesystem* we'll be able to fix the above bugs, remove userspace workarounds, and clearly express the intended semantics: the locked/unlocked status of an encrypted directory is global, and encryption is orthogonal to OS-level access control. Why not use the add_key() syscall ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ We use an ioctl for this API rather than the existing add_key() system call because the ioctl gives us the flexibility needed to implement fscrypt-specific semantics that will be introduced in later patches: - Supporting key removal with the semantics such that the secret is removed immediately and any unused inodes using the key are evicted; also, the eviction of any in-use inodes can be retried. - Calculating a key-dependent cryptographic identifier and returning it to userspace. - Allowing keys to be added and removed by non-root users, but only keys for v2 encryption policies; and to prevent denial-of-service attacks, users can only remove keys they themselves have added, and a key is only really removed after all users who added it have removed it. Trying to shoehorn these semantics into the keyrings syscalls would be very difficult, whereas the ioctls make things much easier. However, to reuse code the implementation still uses the keyrings service internally. Thus we get lockless RCU-mode key lookups without having to re-implement it, and the keys automatically show up in /proc/keys for debugging purposes. References: [1] https://github.com/google/fscrypt [2] https://goo.gl/55cCrI#heading=h.vf09isp98isb [3] https://github.com/google/fscrypt/issues/111#issuecomment-444347939 [4] https://github.com/google/fscrypt/issues/116 [5] https://bugs.launchpad.net/ubuntu/+source/fscrypt/+bug/1770715 [6] https://github.com/google/fscrypt/issues/128 [7] https://askubuntu.com/questions/1130306/cannot-run-docker-on-an-encrypted-filesystem Reviewed-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-07-31Unbreak mount_capable()Al Viro1-4/+1
In "consolidate the capability checks in sget_{fc,userns}())" the wrong argument had been passed to mount_capable() by sget_fc(). That mistake had been further obscured later, when switching mount_capable() to fs_context has moved the calculation of bogus argument from sget_fc() to mount_capable() itself. It should've been fc->user_ns all along. Screwed-up-by: Al Viro <viro@zeniv.linux.org.uk> Reported-by: Christian Brauner <christian@brauner.io> Tested-by: Christian Brauner <christian@brauner.io> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-07-05convenience helper: get_tree_single()Al Viro1-0/+8
counterpart of mount_single(); switch fusectl to it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>