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2021-02-27Merge branch 'work.misc' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted stuff pile - no common topic here" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: whack-a-mole: don't open-code iminor/imajor 9p: fix misuse of sscanf() in v9fs_stat2inode() audit_alloc_mark(): don't open-code ERR_CAST() fs/inode.c: make inode_init_always() initialize i_ino to 0 vfs: don't unnecessarily clone write access for writable fds
2021-02-27Merge tag 'docs-5.12-2' of git://git.lwn.net/linuxLinus Torvalds1-0/+4
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes, nothing all that notable" * tag 'docs-5.12-2' of git://git.lwn.net/linux: docs: proc.rst: fix indentation warning Documentation: cgroup-v2: fix path to example BPF program docs: powerpc: Fix tables in syscall64-abi.rst Documentation: features: refresh feature list Documentation: features: remove c6x references docs: ABI: testing: ima_policy: Fixed missing bracket Fix unaesthetic indentation scripts: kernel-doc: fix array element capture in pointer-to-func parsing doc: use KCFLAGS instead of EXTRA_CFLAGS to pass flags from command line Documentation: proc.rst: add more about the 6 fields in loadavg
2021-02-26seq_file: document how per-entry resources are managed.NeilBrown1-0/+6
Patch series "Fix some seq_file users that were recently broken". A recent change to seq_file broke some users which were using seq_file in a non-"standard" way ... though the "standard" isn't documented, so they can be excused. The result is a possible leak - of memory in one case, of references to a 'transport' in the other. These three patches: 1/ document and explain the problem 2/ fix the problem user in x86 3/ fix the problem user in net/sctp This patch (of 3): Users of seq_file will sometimes find it convenient to take a resource, such as a lock or memory allocation, in the ->start or ->next operations. These are per-entry resources, distinct from per-session resources which are taken in ->start and released in ->stop. The preferred management of these is release the resource on the subsequent call to ->next or ->stop. However prior to Commit 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface") it happened that ->show would always be called after ->start or ->next, and a few users chose to release the resource in ->show. This is no longer reliable. Since the mentioned commit, ->next will always come after a successful ->show (to ensure m->index is updated correctly), so the original ordering cannot be maintained. This patch updates the documentation to clearly state the required behaviour. Other patches will fix the few problematic users. [akpm@linux-foundation.org: fix typo, per Willy] Link: https://lkml.kernel.org/r/161248518659.21478.2484341937387294998.stgit@noble1 Link: https://lkml.kernel.org/r/161248539020.21478.3147971477400875336.stgit@noble1 Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface") Signed-off-by: NeilBrown <neilb@suse.de> Cc: Xin Long <lucien.xin@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-25docs: proc.rst: fix indentation warningRandy Dunlap1-1/+1
Fix indentation snafu in proc.rst as reported by Stephen. next-20210219/Documentation/filesystems/proc.rst:697: WARNING: Unexpected indentation. Fixes: 93ea4a0b8fce ("Documentation: proc.rst: add more about the 6 fields in loadavg") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20210223060418.21443-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-24Merge tag 'idmapped-mounts-v5.12' of ↵Linus Torvalds3-12/+16
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull idmapped mounts from Christian Brauner: "This introduces idmapped mounts which has been in the making for some time. Simply put, different mounts can expose the same file or directory with different ownership. This initial implementation comes with ports for fat, ext4 and with Christoph's port for xfs with more filesystems being actively worked on by independent people and maintainers. Idmapping mounts handle a wide range of long standing use-cases. Here are just a few: - Idmapped mounts make it possible to easily share files between multiple users or multiple machines especially in complex scenarios. For example, idmapped mounts will be used in the implementation of portable home directories in systemd-homed.service(8) where they allow users to move their home directory to an external storage device and use it on multiple computers where they are assigned different uids and gids. This effectively makes it possible to assign random uids and gids at login time. - It is possible to share files from the host with unprivileged containers without having to change ownership permanently through chown(2). - It is possible to idmap a container's rootfs and without having to mangle every file. For example, Chromebooks use it to share the user's Download folder with their unprivileged containers in their Linux subsystem. - It is possible to share files between containers with non-overlapping idmappings. - Filesystem that lack a proper concept of ownership such as fat can use idmapped mounts to implement discretionary access (DAC) permission checking. - They allow users to efficiently changing ownership on a per-mount basis without having to (recursively) chown(2) all files. In contrast to chown (2) changing ownership of large sets of files is instantenous with idmapped mounts. This is especially useful when ownership of a whole root filesystem of a virtual machine or container is changed. With idmapped mounts a single syscall mount_setattr syscall will be sufficient to change the ownership of all files. - Idmapped mounts always take the current ownership into account as idmappings specify what a given uid or gid is supposed to be mapped to. This contrasts with the chown(2) syscall which cannot by itself take the current ownership of the files it changes into account. It simply changes the ownership to the specified uid and gid. This is especially problematic when recursively chown(2)ing a large set of files which is commong with the aforementioned portable home directory and container and vm scenario. - Idmapped mounts allow to change ownership locally, restricting it to specific mounts, and temporarily as the ownership changes only apply as long as the mount exists. Several userspace projects have either already put up patches and pull-requests for this feature or will do so should you decide to pull this: - systemd: In a wide variety of scenarios but especially right away in their implementation of portable home directories. https://systemd.io/HOME_DIRECTORY/ - container runtimes: containerd, runC, LXD:To share data between host and unprivileged containers, unprivileged and privileged containers, etc. The pull request for idmapped mounts support in containerd, the default Kubernetes runtime is already up for quite a while now: https://github.com/containerd/containerd/pull/4734 - The virtio-fs developers and several users have expressed interest in using this feature with virtual machines once virtio-fs is ported. - ChromeOS: Sharing host-directories with unprivileged containers. I've tightly synced with all those projects and all of those listed here have also expressed their need/desire for this feature on the mailing list. For more info on how people use this there's a bunch of talks about this too. Here's just two recent ones: https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf https://fosdem.org/2021/schedule/event/containers_idmap/ This comes with an extensive xfstests suite covering both ext4 and xfs: https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts It covers truncation, creation, opening, xattrs, vfscaps, setid execution, setgid inheritance and more both with idmapped and non-idmapped mounts. It already helped to discover an unrelated xfs setgid inheritance bug which has since been fixed in mainline. It will be sent for inclusion with the xfstests project should you decide to merge this. In order to support per-mount idmappings vfsmounts are marked with user namespaces. The idmapping of the user namespace will be used to map the ids of vfs objects when they are accessed through that mount. By default all vfsmounts are marked with the initial user namespace. The initial user namespace is used to indicate that a mount is not idmapped. All operations behave as before and this is verified in the testsuite. Based on prior discussions we want to attach the whole user namespace and not just a dedicated idmapping struct. This allows us to reuse all the helpers that already exist for dealing with idmappings instead of introducing a whole new range of helpers. In addition, if we decide in the future that we are confident enough to enable unprivileged users to setup idmapped mounts the permission checking can take into account whether the caller is privileged in the user namespace the mount is currently marked with. The user namespace the mount will be marked with can be specified by passing a file descriptor refering to the user namespace as an argument to the new mount_setattr() syscall together with the new MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern of extensibility. The following conditions must be met in order to create an idmapped mount: - The caller must currently have the CAP_SYS_ADMIN capability in the user namespace the underlying filesystem has been mounted in. - The underlying filesystem must support idmapped mounts. - The mount must not already be idmapped. This also implies that the idmapping of a mount cannot be altered once it has been idmapped. - The mount must be a detached/anonymous mount, i.e. it must have been created by calling open_tree() with the OPEN_TREE_CLONE flag and it must not already have been visible in the filesystem. The last two points guarantee easier semantics for userspace and the kernel and make the implementation significantly simpler. By default vfsmounts are marked with the initial user namespace and no behavioral or performance changes are observed. The manpage with a detailed description can be found here: https://git.kernel.org/brauner/man-pages/c/1d7b902e2875a1ff342e036a9f866a995640aea8 In order to support idmapped mounts, filesystems need to be changed and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The patches to convert individual filesystem are not very large or complicated overall as can be seen from the included fat, ext4, and xfs ports. Patches for other filesystems are actively worked on and will be sent out separately. The xfstestsuite can be used to verify that port has been done correctly. The mount_setattr() syscall is motivated independent of the idmapped mounts patches and it's been around since July 2019. One of the most valuable features of the new mount api is the ability to perform mounts based on file descriptors only. Together with the lookup restrictions available in the openat2() RESOLVE_* flag namespace which we added in v5.6 this is the first time we are close to hardened and race-free (e.g. symlinks) mounting and path resolution. While userspace has started porting to the new mount api to mount proper filesystems and create new bind-mounts it is currently not possible to change mount options of an already existing bind mount in the new mount api since the mount_setattr() syscall is missing. With the addition of the mount_setattr() syscall we remove this last restriction and userspace can now fully port to the new mount api, covering every use-case the old mount api could. We also add the crucial ability to recursively change mount options for a whole mount tree, both removing and adding mount options at the same time. This syscall has been requested multiple times by various people and projects. There is a simple tool available at https://github.com/brauner/mount-idmapped that allows to create idmapped mounts so people can play with this patch series. I'll add support for the regular mount binary should you decide to pull this in the following weeks: Here's an example to a simple idmapped mount of another user's home directory: u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt u1001@f2-vm:/$ ls -al /home/ubuntu/ total 28 drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 . drwxr-xr-x 4 root root 4096 Oct 28 04:00 .. -rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile -rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ ls -al /mnt/ total 28 drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 . drwxr-xr-x 29 root root 4096 Oct 28 22:01 .. -rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile -rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ touch /mnt/my-file u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file u1001@f2-vm:/$ ls -al /mnt/my-file -rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file u1001@f2-vm:/$ ls -al /home/ubuntu/my-file -rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file u1001@f2-vm:/$ getfacl /mnt/my-file getfacl: Removing leading '/' from absolute path names # file: mnt/my-file # owner: u1001 # group: u1001 user::rw- user:u1001:rwx group::rw- mask::rwx other::r-- u1001@f2-vm:/$ getfacl /home/ubuntu/my-file getfacl: Removing leading '/' from absolute path names # file: home/ubuntu/my-file # owner: ubuntu # group: ubuntu user::rw- user:ubuntu:rwx group::rw- mask::rwx other::r--" * tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits) xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl xfs: support idmapped mounts ext4: support idmapped mounts fat: handle idmapped mounts tests: add mount_setattr() selftests fs: introduce MOUNT_ATTR_IDMAP fs: add mount_setattr() fs: add attr_flags_to_mnt_flags helper fs: split out functions to hold writers namespace: only take read lock in do_reconfigure_mnt() mount: make {lock,unlock}_mount_hash() static namespace: take lock_mount_hash() directly when changing flags nfs: do not export idmapped mounts overlayfs: do not mount on top of idmapped mounts ecryptfs: do not mount on top of idmapped mounts ima: handle idmapped mounts apparmor: handle idmapped mounts fs: make helpers idmap mount aware exec: handle idmapped mounts would_dump: handle idmapped mounts ...
2021-02-23Merge tag 'lazytime_for_v5.12-rc1' of ↵Linus Torvalds1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull lazytime updates from Jan Kara: "Cleanups of the lazytime handling in the writeback code making rules for calling ->dirty_inode() filesystem handlers saner" * tag 'lazytime_for_v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: ext4: simplify i_state checks in __ext4_update_other_inode_time() gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync() fs: improve comments for writeback_single_inode() fs: drop redundant check from __writeback_single_inode() fs: clean up __mark_inode_dirty() a bit fs: pass only I_DIRTY_INODE flags to ->dirty_inode fs: don't call ->dirty_inode for lazytime timestamp updates fat: only specify I_DIRTY_TIME when needed in fat_update_time() fs: only specify I_DIRTY_TIME when needed in generic_update_time() fs: correctly document the inode dirty flags
2021-02-22Documentation: proc.rst: add more about the 6 fields in loadavgRandy Dunlap1-0/+4
Address Jon's feedback on the previous patch by adding info about field separators in the /proc/loadavg file. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20210222034729.22350-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-22Merge tag 'docs-5.12' of git://git.lwn.net/linuxLinus Torvalds5-20/+13
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 ...
2021-02-21Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-blockLinus Torvalds2-1/+16
Pull core block updates from Jens Axboe: "Another nice round of removing more code than what is added, mostly due to Christoph's relentless pursuit of tech debt removal/cleanups. This pull request contains: - Two series of BFQ improvements (Paolo, Jan, Jia) - Block iov_iter improvements (Pavel) - bsg error path fix (Pan) - blk-mq scheduler improvements (Jan) - -EBUSY discard fix (Jan) - bvec allocation improvements (Ming, Christoph) - bio allocation and init improvements (Christoph) - Store bdev pointer in bio instead of gendisk + partno (Christoph) - Block trace point cleanups (Christoph) - hard read-only vs read-only split (Christoph) - Block based swap cleanups (Christoph) - Zoned write granularity support (Damien) - Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)" * tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits) mm: simplify swapdev_block sd_zbc: clear zone resources for non-zoned case block: introduce blk_queue_clear_zone_settings() zonefs: use zone write granularity as block size block: introduce zone_write_granularity limit block: use blk_queue_set_zoned in add_partition() nullb: use blk_queue_set_zoned() to setup zoned devices nvme: cleanup zone information initialization block: document zone_append_max_bytes attribute block: use bi_max_vecs to find the bvec pool md/raid10: remove dead code in reshape_request block: mark the bio as cloned in bio_iov_bvec_set block: set BIO_NO_PAGE_REF in bio_iov_bvec_set block: remove a layer of indentation in bio_iov_iter_get_pages block: turn the nr_iovecs argument to bio_alloc* into an unsigned short block: remove the 1 and 4 vec bvec_slabs entries block: streamline bvec_alloc block: factor out a bvec_alloc_gfp helper block: move struct biovec_slab to bio.c block: reuse BIO_INLINE_VECS for integrity bvecs ...
2021-02-21Merge tag 'fsverity-for-linus' of ↵Linus Torvalds1-0/+76
git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt Pull fsverity updates from Eric Biggers: "Add an ioctl which allows reading fs-verity metadata from a file. This is useful when a file with fs-verity enabled needs to be served somewhere, and the other end wants to do its own fs-verity compatible verification of the file. See the commit messages for details. This new ioctl has been tested using new xfstests I've written for it" * tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt: fs-verity: support reading signature with ioctl fs-verity: support reading descriptor with ioctl fs-verity: support reading Merkle tree with ioctl fs-verity: add FS_IOC_READ_VERITY_METADATA ioctl fs-verity: don't pass whole descriptor to fsverity_verify_signature() fs-verity: factor out fsverity_get_descriptor()
2021-02-21Merge tag 'f2fs-for-5.12-rc1' of ↵Linus Torvalds1-1/+17
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "We've added two major features: 1) compression level and 2) checkpoint_merge, in this round. Compression level expands 'compress_algorithm' mount option to accept parameter as format of <algorithm>:<level>, by this way, it gives a way to allow user to do more specified config on lz4 and zstd compression level, then f2fs compression can provide higher compress ratio. checkpoint_merge creates a kernel daemon and makes it to merge concurrent checkpoint requests as much as possible to eliminate redundant checkpoint issues. Plus, we can eliminate the sluggish issue caused by slow checkpoint operation when the checkpoint is done in a process context in a cgroup having low i/o budget and cpu shares. Enhancements: - add compress level for lz4 and zstd in mount option - checkpoint_merge mount option - deprecate f2fs_trace_io Bug fixes: - flush data when enabling checkpoint back - handle corner cases of mount options - missing ACL update and lock for I_LINKABLE flag - attach FIEMAP_EXTENT_MERGED in f2fs_fiemap - fix potential deadlock in compression flow - fix wrong submit_io condition As usual, we've cleaned up many code flows and fixed minor bugs" * tag 'f2fs-for-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (32 commits) Documentation: f2fs: fix typo s/automaic/automatic f2fs: give a warning only for readonly partition f2fs: don't grab superblock freeze for flush/ckpt thread f2fs: add ckpt_thread_ioprio sysfs node f2fs: introduce checkpoint_merge mount option f2fs: relocate inline conversion from mmap() to mkwrite() f2fs: fix a wrong condition in __submit_bio f2fs: remove unnecessary initialization in xattr.c f2fs: fix to avoid inconsistent quota data f2fs: flush data when enabling checkpoint back f2fs: deprecate f2fs_trace_io f2fs: Remove readahead collision detection f2fs: remove unused stat_{inc, dec}_atomic_write f2fs: introduce sb_status sysfs node f2fs: fix to use per-inode maxbytes f2fs: compress: fix potential deadlock libfs: unexport generic_ci_d_compare() and generic_ci_d_hash() f2fs: fix to set/clear I_LINKABLE under i_lock f2fs: fix null page reference in redirty_blocks f2fs: clean up post-read processing ...
2021-02-16Documentation: f2fs: fix typo s/automaic/automaticEd Tsai1-1/+1
Fix typo in f2fs documentation. Signed-off-by: Ed Tsai <ed.tsai@mediatek.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-02-08fs-verity: support reading signature with ioctlEric Biggers1-1/+8
Add support for FS_VERITY_METADATA_TYPE_SIGNATURE to FS_IOC_READ_VERITY_METADATA. This allows a userspace server program to retrieve the built-in signature (if present) of a verity file for serving to a client which implements fs-verity compatible verification. See the patch which introduced FS_IOC_READ_VERITY_METADATA for more details. The ability for userspace to read the built-in signatures is also useful because it allows a system that is using the in-kernel signature verification to migrate to userspace signature verification. This has been tested using a new xfstest which calls this ioctl via a new subcommand for the 'fsverity' program from fsverity-utils. Link: https://lore.kernel.org/r/20210115181819.34732-7-ebiggers@kernel.org Reviewed-by: Victor Hsieh <victorhsieh@google.com> Reviewed-by: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2021-02-08fs-verity: support reading descriptor with ioctlEric Biggers1-0/+4
Add support for FS_VERITY_METADATA_TYPE_DESCRIPTOR to FS_IOC_READ_VERITY_METADATA. This allows a userspace server program to retrieve the fs-verity descriptor of a file for serving to a client which implements fs-verity compatible verification. See the patch which introduced FS_IOC_READ_VERITY_METADATA for more details. "fs-verity descriptor" here means only the part that userspace cares about because it is hashed to produce the file digest. It doesn't include the signature which ext4 and f2fs append to the fsverity_descriptor struct when storing it on-disk, since that way of storing the signature is an implementation detail. The next patch adds a separate metadata_type value for retrieving the signature separately. This has been tested using a new xfstest which calls this ioctl via a new subcommand for the 'fsverity' program from fsverity-utils. Link: https://lore.kernel.org/r/20210115181819.34732-6-ebiggers@kernel.org Reviewed-by: Victor Hsieh <victorhsieh@google.com> Reviewed-by: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2021-02-08fs-verity: support reading Merkle tree with ioctlEric Biggers1-1/+9
Add support for FS_VERITY_METADATA_TYPE_MERKLE_TREE to FS_IOC_READ_VERITY_METADATA. This allows a userspace server program to retrieve the Merkle tree of a verity file for serving to a client which implements fs-verity compatible verification. See the patch which introduced FS_IOC_READ_VERITY_METADATA for more details. This has been tested using a new xfstest which calls this ioctl via a new subcommand for the 'fsverity' program from fsverity-utils. Link: https://lore.kernel.org/r/20210115181819.34732-5-ebiggers@kernel.org Reviewed-by: Victor Hsieh <victorhsieh@google.com> Reviewed-by: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2021-02-08fs-verity: add FS_IOC_READ_VERITY_METADATA ioctlEric Biggers1-0/+57
Add an ioctl FS_IOC_READ_VERITY_METADATA which will allow reading verity metadata from a file that has fs-verity enabled, including: - The Merkle tree - The fsverity_descriptor (not including the signature if present) - The built-in signature, if present This ioctl has similar semantics to pread(). It is passed the type of metadata to read (one of the above three), and a buffer, offset, and size. It returns the number of bytes read or an error. Separate patches will add support for each of the above metadata types. This patch just adds the ioctl itself. This ioctl doesn't make any assumption about where the metadata is stored on-disk. It does assume the metadata is in a stable format, but that's basically already the case: - The Merkle tree and fsverity_descriptor are defined by how fs-verity file digests are computed; see the "File digest computation" section of Documentation/filesystems/fsverity.rst. Technically, the way in which the levels of the tree are ordered relative to each other wasn't previously specified, but it's logical to put the root level first. - The built-in signature is the value passed to FS_IOC_ENABLE_VERITY. This ioctl is useful because it allows writing a server program that takes a verity file and serves it to a client program, such that the client can do its own fs-verity compatible verification of the file. This only makes sense if the client doesn't trust the server and if the server needs to provide the storage for the client. More concretely, there is interest in using this ability in Android to export APK files (which are protected by fs-verity) to "protected VMs". This would use Protected KVM (https://lwn.net/Articles/836693), which provides an isolated execution environment without having to trust the traditional "host". A "guest" VM can boot from a signed image and perform specific tasks in a minimum trusted environment using files that have fs-verity enabled on the host, without trusting the host or requiring that the guest has its own trusted storage. Technically, it would be possible to duplicate the metadata and store it in separate files for serving. However, that would be less efficient and would require extra care in userspace to maintain file consistency. In addition to the above, the ability to read the built-in signatures is useful because it allows a system that is using the in-kernel signature verification to migrate to userspace signature verification. Link: https://lore.kernel.org/r/20210115181819.34732-4-ebiggers@kernel.org Reviewed-by: Victor Hsieh <victorhsieh@google.com> Acked-by: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2021-02-05Documentation: /proc/loadavg: add 3 more field descriptionsRandy Dunlap1-1/+4
Update contents of /proc/loadavg: add 3 more fields. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/fe55b139-bd03-4762-199b-83be873cf7dd@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-04f2fs: introduce checkpoint_merge mount optionDaeho Jeong1-0/+11
We've added a new mount options, "checkpoint_merge" and "nocheckpoint_merge", which creates a kernel daemon and makes it to merge concurrent checkpoint requests as much as possible to eliminate redundant checkpoint issues. Plus, we can eliminate the sluggish issue caused by slow checkpoint operation when the checkpoint is done in a process context in a cgroup having low i/o budget and cpu shares. To make this do better, we set the default i/o priority of the kernel daemon to "3", to give one higher priority than other kernel threads. The below verification result explains this. The basic idea has come from https://opensource.samsung.com. [Verification] Android Pixel Device(ARM64, 7GB RAM, 256GB UFS) Create two I/O cgroups (fg w/ weight 100, bg w/ wight 20) Set "strict_guarantees" to "1" in BFQ tunables In "fg" cgroup, - thread A => trigger 1000 checkpoint operations "for i in `seq 1 1000`; do touch test_dir1/file; fsync test_dir1; done" - thread B => gererating async. I/O "fio --rw=write --numjobs=1 --bs=128k --runtime=3600 --time_based=1 --filename=test_img --name=test" In "bg" cgroup, - thread C => trigger repeated checkpoint operations "echo $$ > /dev/blkio/bg/tasks; while true; do touch test_dir2/file; fsync test_dir2; done" We've measured thread A's execution time. [ w/o patch ] Elapsed Time: Avg. 68 seconds [ w/ patch ] Elapsed Time: Avg. 48 seconds Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> [Jaegeuk Kim: fix the return value in f2fs_start_ckpt_thread, reported by Dan] Signed-off-by: Daeho Jeong <daehojeong@google.com> Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-01-28ovl: implement volatile-specific fsync error behaviourSargun Dhillon1-0/+8
Overlayfs's volatile option allows the user to bypass all forced sync calls to the upperdir filesystem. This comes at the cost of safety. We can never ensure that the user's data is intact, but we can make a best effort to expose whether or not the data is likely to be in a bad state. The best way to handle this in the time being is that if an overlayfs's upperdir experiences an error after a volatile mount occurs, that error will be returned on fsync, fdatasync, sync, and syncfs. This is contradictory to the traditional behaviour of VFS which fails the call once, and only raises an error if a subsequent fsync error has occurred, and been raised by the filesystem. One awkward aspect of the patch is that we have to manually set the superblock's errseq_t after the sync_fs callback as opposed to just returning an error from syncfs. This is because the call chain looks something like this: sys_syncfs -> sync_filesystem -> __sync_filesystem -> /* The return value is ignored here sb->s_op->sync_fs(sb) _sync_blockdev /* Where the VFS fetches the error to raise to userspace */ errseq_check_and_advance Because of this we call errseq_set every time the sync_fs callback occurs. Due to the nature of this seen / unseen dichotomy, if the upperdir is an inconsistent state at the initial mount time, overlayfs will refuse to mount, as overlayfs cannot get a snapshot of the upperdir's errseq that will increment on error until the user calls syncfs. Signed-off-by: Sargun Dhillon <sargun@sargun.me> Suggested-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Fixes: c86243b090bc ("ovl: provide a mount option "volatile"") Cc: stable@vger.kernel.org Reviewed-by: Vivek Goyal <vgoyal@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2021-01-28f2fs: compress: support compress levelChao Yu1-0/+5
Expand 'compress_algorithm' mount option to accept parameter as format of <algorithm>:<level>, by this way, it gives a way to allow user to do more specified config on lz4 and zstd compression level, then f2fs compression can provide higher compress ratio. In order to set compress level for lz4 algorithm, it needs to set CONFIG_LZ4HC_COMPRESS and CONFIG_F2FS_FS_LZ4HC config to enable lz4hc compress algorithm. CR and performance number on lz4/lz4hc algorithm: dd if=enwik9 of=compressed_file conv=fsync Original blocks: 244382 lz4 lz4hc-9 compressed blocks 170647 163270 compress ratio 69.8% 66.8% speed 16.4207 s, 60.9 MB/s 26.7299 s, 37.4 MB/s compress ratio = after / before Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-01-27f2fs: remove FAULT_ALLOC_BIOChristoph Hellwig1-1/+0
Sleeping bio allocations do not fail, which means that injecting an error into sleeping bio allocations is a little silly. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Acked-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-25bio: don't copy bvec for direct IOPavel Begunkov1-0/+9
The block layer spends quite a while in blkdev_direct_IO() to copy and initialise bio's bvec. However, if we've already got a bvec in the input iterator it might be reused in some cases, i.e. when new ITER_BVEC_FLAG_FIXED flag is set. Simple tests show considerable performance boost, and it also reduces memory footprint. Suggested-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-25bvec/iter: disallow zero-length segment bvecsPavel Begunkov1-0/+7
zero-length bvec segments are allowed in general, but not handled by bio and down the block layer so filtered out. This inconsistency may be confusing and prevent from optimisations. As zero-length segments are useless and places that were generating them are patched, declare them not allowed. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24fs: make helpers idmap mount awareChristian Brauner1-9/+10
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>
2021-01-24acl: handle idmapped mountsChristian Brauner2-3/+6
The posix acl permission checking helpers determine whether a caller is privileged over an inode according to the acls associated with the inode. Add helpers that make it possible to handle acls on idmapped mounts. The vfs and the filesystems targeted by this first iteration make use of posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to translate basic posix access and default permissions such as the ACL_USER and ACL_GROUP type according to the initial user namespace (or the superblock's user namespace) to and from the caller's current user namespace. Adapt these two helpers to handle idmapped mounts whereby we either map from or into the mount's user namespace depending on in which direction we're translating. Similarly, cap_convert_nscap() is used by the vfs to translate user namespace and non-user namespace aware filesystem capabilities from the superblock's user namespace to the caller's user namespace. Enable it to handle idmapped mounts by accounting for the mount's user namespace. In addition the fileystems targeted in the first iteration of this patch series make use of the posix_acl_chmod() and, posix_acl_update_mode() helpers. Both helpers perform permission checks on the target inode. Let them handle idmapped mounts. These two helpers are called when posix acls are set by the respective filesystems to handle this case we extend the ->set() method to take an additional user namespace argument to pass the mount's user namespace down. Link: https://lore.kernel.org/r/20210121131959.646623-9-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>
2021-01-22AFS: Documentation: fix a few typos in afs.rstRandy Dunlap1-4/+4
Fix typos (punctuation, grammar, spelling) in afs.rst. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: linux-afs@lists.infradead.org Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20210117213351.1075-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-13fs: pass only I_DIRTY_INODE flags to ->dirty_inodeEric Biggers1-1/+4
->dirty_inode is now only called when I_DIRTY_INODE (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) is set. However it may still be passed other dirty flags at the same time, provided that these other flags happened to be passed to __mark_inode_dirty() at the same time as I_DIRTY_INODE. This doesn't make sense because there is no reason for filesystems to care about these extra flags. Nor are filesystems notified about all updates to these other flags. Therefore, mask the flags before passing them to ->dirty_inode. Also properly document ->dirty_inode in vfs.rst. Link: https://lore.kernel.org/r/20210112190253.64307-7-ebiggers@kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jan Kara <jack@suse.cz>
2021-01-11docs: Include ext4 documentation via filesystems/Jonathan Neuschäfer1-0/+1
The documentation for other filesystems is already included via filesystems/index.rst. Include ext4 in the same way and remove it from the top-level table of contents. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Link: https://lore.kernel.org/r/20210101215215.1047826-1-j.neuschaefer@gmx.net Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-11Documentation/dax: Update description of DAX policy changingHao Li1-14/+3
After commit 77573fa310d9 ("fs: Kill DCACHE_DONTCACHE dentry even if DCACHE_REFERENCED is set"), changes to DAX policy will take effect as soon as all references to this file are gone. Update the documentation accordingly. Signed-off-by: Hao Li <lihao2018.fnst@cn.fujitsu.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20210106015000.5263-1-lihao2018.fnst@cn.fujitsu.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-11docs: filesystems: vfs: Correct the struct nameLiao Pingfang1-1/+1
The struct name should be file_system_type instead of file_system_operations. Signed-off-by: Liao Pingfang <winndows@163.com> Link: https://lore.kernel.org/r/1610265599-5101-1-git-send-email-winndows@163.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-04vfs: don't unnecessarily clone write access for writable fdsEric Biggers1-0/+7
There's no need for mnt_want_write_file() to increment mnt_writers when the file is already open for writing, provided that mnt_drop_write_file() is changed to conditionally decrement it. We seem to have ended up in the current situation because mnt_want_write_file() used to be paired with mnt_drop_write(), due to mnt_drop_write_file() not having been added yet. So originally mnt_want_write_file() had to always increment mnt_writers. But later mnt_drop_write_file() was added, and all callers of mnt_want_write_file() were paired with it. This makes the compatibility between mnt_want_write_file() and mnt_drop_write() no longer necessary. Therefore, make __mnt_want_write_file() and __mnt_drop_write_file() skip incrementing mnt_writers on files already open for writing. This removes the only caller of mnt_clone_write(), so remove that too. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-12-25Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-0/+50
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Various bug fixes and cleanups for ext4; no new features this cycle" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (29 commits) ext4: remove unnecessary wbc parameter from ext4_bio_write_page ext4: avoid s_mb_prefetch to be zero in individual scenarios ext4: defer saving error info from atomic context ext4: simplify ext4 error translation ext4: move functions in super.c ext4: make ext4_abort() use __ext4_error() ext4: standardize error message in ext4_protect_reserved_inode() ext4: remove redundant sb checksum recomputation ext4: don't remount read-only with errors=continue on reboot ext4: fix deadlock with fs freezing and EA inodes jbd2: add a helper to find out number of fast commit blocks ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h ext4: fix fall-through warnings for Clang ext4: add docs about fast commit idempotence ext4: remove the unused EXT4_CURRENT_REV macro ext4: fix an IS_ERR() vs NULL check ext4: check for invalid block size early when mounting a file system ext4: fix a memory leak of ext4_free_data ext4: delete nonsensical (commented-out) code inside ext4_xattr_block_set() ext4: update ext4_data_block_valid related comments ...
2020-12-20Merge tag 'gfs2-for-5.11' of ↵Linus Torvalds1-19/+18
git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 updates from Andreas Gruenbacher: - Don't wait for unfreeze of the wrong filesystems - Remove an obsolete delete_work_func hack and an incorrect sb_start_write - Minor documentation updates and cosmetic care * tag 'gfs2-for-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: gfs2: in signal_our_withdraw wait for unfreeze of _this_ fs only gfs2: Remove sb_start_write from gfs2_statfs_sync gfs2: remove trailing semicolons from macro definitions Revert "GFS2: Prevent delete work from occurring on glocks used for create" gfs2: Make inode operations static MAINTAINERS: Add gfs2 bug tracker link Documentation: Update filesystems/gfs2.rst
2020-12-17Merge tag 'ovl-update-5.11' of ↵Linus Torvalds1-8/+28
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: - Allow unprivileged mounting in a user namespace. For quite some time the security model of overlayfs has been that operations on underlying layers shall be performed with the privileges of the mounting task. This way an unprvileged user cannot gain privileges by the act of mounting an overlayfs instance. A full audit of all function calls made by the overlayfs code has been performed to see whether they conform to this model, and this branch contains some fixes in this regard. - Support running on copied filesystem images by optionally disabling UUID verification. - Bug fixes as well as documentation updates. * tag 'ovl-update-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: unprivieged mounts ovl: do not get metacopy for userxattr ovl: do not fail because of O_NOATIME ovl: do not fail when setting origin xattr ovl: user xattr ovl: simplify file splice ovl: make ioctl() safe ovl: check privs before decoding file handle vfs: verify source area in vfs_dedupe_file_range_one() vfs: move cap_convert_nscap() call into vfs_setxattr() ovl: fix incorrect extent info in metacopy case ovl: expand warning in ovl_d_real() ovl: document lower modification caveats ovl: warn about orphan metacopy ovl: doc clarification ovl: introduce new "uuid=off" option for inodes index feature ovl: propagate ovl_fs to ovl_decode_real_fh and ovl_encode_real_fh
2020-12-17Merge tag 'f2fs-for-5.11-rc1' of ↵Linus Torvalds1-0/+36
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "In this round, we've made more work into per-file compression support. For example, F2FS_IOC_GET | SET_COMPRESS_OPTION provides a way to change the algorithm or cluster size per file. F2FS_IOC_COMPRESS | DECOMPRESS_FILE provides a way to compress and decompress the existing normal files manually. There is also a new mount option, compress_mode=fs|user, which can control who compresses the data. Chao also added a checksum feature with a mount option so that we are able to detect any corrupted cluster. In addition, Daniel contributed casefolding with encryption patch, which will be used for Android devices. Summary: Enhancements: - add ioctls and mount option to manage per-file compression feature - support casefolding with encryption - support checksum for compressed cluster - avoid IO starvation by replacing mutex with rwsem - add sysfs, max_io_bytes, to control max bio size Bug fixes: - fix use-after-free issue when compression and fsverity are enabled - fix consistency corruption during fault injection test - fix data offset for lseek - get rid of buffer_head which has 32bits limit in fiemap - fix some bugs in multi-partitions support - fix nat entry count calculation in shrinker - fix some stat information And, we've refactored some logics and fix minor bugs as well" * tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (36 commits) f2fs: compress: fix compression chksum f2fs: fix shift-out-of-bounds in sanity_check_raw_super() f2fs: fix race of pending_pages in decompression f2fs: fix to account inline xattr correctly during recovery f2fs: inline: fix wrong inline inode stat f2fs: inline: correct comment in f2fs_recover_inline_data f2fs: don't check PAGE_SIZE again in sanity_check_raw_super() f2fs: convert to F2FS_*_INO macro f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size f2fs: don't allow any writes on readonly mount f2fs: avoid race condition for shrinker count f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE f2fs: add compress_mode mount option f2fs: Remove unnecessary unlikely() f2fs: init dirty_secmap incorrectly f2fs: remove buffer_head which has 32bits limit f2fs: fix wrong block count instead of bytes f2fs: use new conversion functions between blks and bytes f2fs: rename logical_to_blk and blk_to_logical f2fs: fix kbytes written stat for multi-device case ...
2020-12-17Merge tag 'for_v5.11-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull ext2, reiserfs, quota and writeback updates from Jan Kara: - a couple of quota fixes (mostly for problems found by syzbot) - several ext2 cleanups - one fix for reiserfs crash on corrupted image - a fix for spurious warning in writeback code * tag 'for_v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: writeback: don't warn on an unregistered BDI in __mark_inode_dirty fs: quota: fix array-index-out-of-bounds bug by passing correct argument to vfs_cleanup_quota_inode() reiserfs: add check for an invalid ih_entry_count ext2: Fix fall-through warnings for Clang fs/ext2: Use ext2_put_page docs: filesystems: Reduce ext2.rst to one top-level heading quota: Sanity-check quota file headers on load quota: Don't overflow quota file offsets ext2: Remove unnecessary blank fs/quota: update quota state flags scheme with project quota flags
2020-12-17ext4: add docs about fast commit idempotenceHarshad Shirwadkar1-0/+50
Fast commit on-disk format is designed such that the replay of these tags can be idempotent. This patch adds documentation in the code in form of comments and in form kernel docs that describes these characteristics. This patch also adds a TODO item needed to ensure kernel fast commit replay idempotence. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://lore.kernel.org/r/20201119232822.1860882-1-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-16Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+2
Merge yet more updates from Andrew Morton: - lots of little subsystems - a few post-linux-next MM material. Most of the rest awaits more merging of other trees. Subsystems affected by this series: alpha, procfs, misc, core-kernel, bitmap, lib, lz4, checkpatch, nilfs, kdump, rapidio, gcov, bfs, relay, resource, ubsan, reboot, fault-injection, lzo, apparmor, and mm (swap, memory-hotplug, pagemap, cleanups, and gup). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (86 commits) mm: fix some spelling mistakes in comments mm: simplify follow_pte{,pmd} mm: unexport follow_pte_pmd apparmor: remove duplicate macro list_entry_is_head() lib/lzo/lzo1x_compress.c: make lzogeneric1x_1_compress() static fault-injection: handle EI_ETYPE_TRUE reboot: hide from sysfs not applicable settings reboot: allow to override reboot type if quirks are found reboot: remove cf9_safe from allowed types and rename cf9_force reboot: allow to specify reboot mode via sysfs reboot: refactor and comment the cpu selection code lib/ubsan.c: mark type_check_kinds with static keyword kcov: don't instrument with UBSAN ubsan: expand tests and reporting ubsan: remove UBSAN_MISC in favor of individual options ubsan: enable for all*config builds ubsan: disable UBSAN_TRAP for all*config ubsan: disable object-size sanitizer under GCC ubsan: move cc-option tests into Kconfig ubsan: remove redundant -Wno-maybe-uninitialized ...
2020-12-16proc: provide details on indirect branch speculationAnand K Mistry1-0/+2
Similar to speculation store bypass, show information about the indirect branch speculation mode of a task in /proc/$pid/status. For testing/benchmarking, I needed to see whether IB (Indirect Branch) speculation (see Spectre-v2) is enabled on a task, to see whether an IBPB instruction should be executed on an address space switch. Unfortunately, this information isn't available anywhere else and currently the only way to get it is to hack the kernel to expose it (like this change). It also helped expose a bug with conditional IB speculation on certain CPUs. Another place this could be useful is to audit the system when using sanboxing. With this change, I can confirm that seccomp-enabled process have IB speculation force disabled as expected when the kernel command line parameter `spectre_v2_user=seccomp`. Since there's already a 'Speculation_Store_Bypass' field, I used that as precedent for adding this one. [amistry@google.com: remove underscores from field name to workaround documentation issue] Link: https://lkml.kernel.org/r/20201106131015.v2.1.I7782b0cedb705384a634cfd8898eb7523562da99@changeid Link: https://lkml.kernel.org/r/20201030172731.1.I7782b0cedb705384a634cfd8898eb7523562da99@changeid Signed-off-by: Anand K Mistry <amistry@google.com> Cc: Anthony Steinhauser <asteinhauser@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Anand K Mistry <amistry@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Alexey Gladkov <gladkov.alexey@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <keescook@chromium.org> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: NeilBrown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-16Merge branch 'exec-for-v5.11' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull execve updates from Eric Biederman: "This set of changes ultimately fixes the interaction of posix file lock and exec. Fundamentally most of the change is just moving where unshare_files is called during exec, and tweaking the users of files_struct so that the count of files_struct is not unnecessarily played with. Along the way fcheck and related helpers were renamed to more accurately reflect what they do. There were also many other small changes that fell out, as this is the first time in a long time much of this code has been touched. Benchmarks haven't turned up any practical issues but Al Viro has observed a possibility for a lot of pounding on task_lock. So I have some changes in progress to convert put_files_struct to always rcu free files_struct. That wasn't ready for the merge window so that will have to wait until next time" * 'exec-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) exec: Move io_uring_task_cancel after the point of no return coredump: Document coredump code exclusively used by cell spufs file: Remove get_files_struct file: Rename __close_fd_get_file close_fd_get_file file: Replace ksys_close with close_fd file: Rename __close_fd to close_fd and remove the files parameter file: Merge __alloc_fd into alloc_fd file: In f_dupfd read RLIMIT_NOFILE once. file: Merge __fd_install into fd_install proc/fd: In fdinfo seq_show don't use get_files_struct bpf/task_iter: In task_file_seq_get_next use task_lookup_next_fd_rcu proc/fd: In proc_readfd_common use task_lookup_next_fd_rcu file: Implement task_lookup_next_fd_rcu kcmp: In get_file_raw_ptr use task_lookup_fd_rcu proc/fd: In tid_fd_mode use task_lookup_fd_rcu file: Implement task_lookup_fd_rcu file: Rename fcheck lookup_fd_rcu file: Replace fcheck_files with files_lookup_fd_rcu file: Factor files_lookup_fd_locked out of fcheck_files file: Rename __fcheck_files to files_lookup_fd_raw ...
2020-12-16Merge tag 'nfsd-5.11' of git://git.linux-nfs.org/projects/cel/cel-2.6Linus Torvalds1-0/+52
Pull nfsd updates from Chuck Lever: "Several substantial changes this time around: - Previously, exporting an NFS mount via NFSD was considered to be an unsupported feature. With v5.11, the community has attempted to make re-exporting a first-class feature of NFSD. This would enable the Linux in-kernel NFS server to be used as an intermediate cache for a remotely-located primary NFS server, for example, even with other NFS server implementations, like a NetApp filer, as the primary. - A short series of patches brings support for multiple RPC/RDMA data chunks per RPC transaction to the Linux NFS server's RPC/RDMA transport implementation. This is a part of the RPC/RDMA spec that the other premiere NFS/RDMA implementation (Solaris) has had for a very long time, and completes the implementation of RPC/RDMA version 1 in the Linux kernel's NFS server. - Long ago, NFSv4 support was introduced to NFSD using a series of C macros that hid dprintk's and goto's. Over time, the kernel's XDR implementation has been greatly improved, but these C macros have remained and become fallow. A series of patches in this pull request completely replaces those macros with the use of current kernel XDR infrastructure. Benefits include: - More robust input sanitization in NFSD's NFSv4 XDR decoders. - Make it easier to use common kernel library functions that use XDR stream APIs (for example, GSS-API). - Align the structure of the source code with the RFCs so it is easier to learn, verify, and maintain our XDR implementation. - Removal of more than a hundred hidden dprintk() call sites. - Removal of some explicit manipulation of pages to help make the eventual transition to xdr->bvec smoother. - On top of several related fixes in 5.10-rc, there are a few more fixes to get the Linux NFSD implementation of NFSv4.2 inter-server copy up to speed. And as usual, there is a pinch of seasoning in the form of a collection of unrelated minor bug fixes and clean-ups. Many thanks to all who contributed this time around!" * tag 'nfsd-5.11' of git://git.linux-nfs.org/projects/cel/cel-2.6: (131 commits) nfsd: Record NFSv4 pre/post-op attributes as non-atomic nfsd: Set PF_LOCAL_THROTTLE on local filesystems only nfsd: Fix up nfsd to ensure that timeout errors don't result in ESTALE exportfs: Add a function to return the raw output from fh_to_dentry() nfsd: close cached files prior to a REMOVE or RENAME that would replace target nfsd: allow filesystems to opt out of subtree checking nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations Revert "nfsd4: support change_attr_type attribute" nfsd4: don't query change attribute in v2/v3 case nfsd: minor nfsd4_change_attribute cleanup nfsd: simplify nfsd4_change_info nfsd: only call inode_query_iversion in the I_VERSION case nfs_common: need lock during iterate through the list NFSD: Fix 5 seconds delay when doing inter server copy NFSD: Fix sparse warning in nfs4proc.c SUNRPC: Remove XDRBUF_SPARSE_PAGES flag in gss_proxy upcall sunrpc: clean-up cache downcall nfsd: Fix message level for normal termination NFSD: Remove macros that are no longer used NFSD: Replace READ* macros in nfsd4_decode_compound() ...
2020-12-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-4/+4
Merge misc updates from Andrew Morton: - a few random little subsystems - almost all of the MM patches which are staged ahead of linux-next material. I'll trickle to post-linux-next work in as the dependents get merged up. Subsystems affected by this patch series: kthread, kbuild, ide, ntfs, ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation, kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction, oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc, uaccess, zram, and cleanups). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits) mm: cleanup kstrto*() usage mm: fix fall-through warnings for Clang mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at mm: shmem: convert shmem_enabled_show to use sysfs_emit_at mm:backing-dev: use sysfs_emit in macro defining functions mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening mm: use sysfs_emit for struct kobject * uses mm: fix kernel-doc markups zram: break the strict dependency from lzo zram: add stat to gather incompressible pages since zram set up zram: support page writeback mm/process_vm_access: remove redundant initialization of iov_r mm/zsmalloc.c: rework the list_add code in insert_zspage() mm/zswap: move to use crypto_acomp API for hardware acceleration mm/zswap: fix passing zero to 'PTR_ERR' warning mm/zswap: make struct kernel_param_ops definitions const userfaultfd/selftests: hint the test runner on required privilege userfaultfd/selftests: fix retval check for userfaultfd_open() userfaultfd/selftests: always dump something in modes userfaultfd: selftests: make __{s,u}64 format specifiers portable ...
2020-12-15tmpfs: fix Documentation nitsRandy Dunlap1-4/+4
Fix a typo, punctuation, use uppercase for CPUs, and limit tmpfs to keeping only its files in virtual memory (phrasing). Link: https://lkml.kernel.org/r/20201202010934.18566-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Hugh Dickins <hughd@google.com> Cc: Chris Down <chris@chrisdown.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15Merge tag 'docs-5.11' of git://git.lwn.net/linuxLinus Torvalds3-3/+4
Pull documentation updates from Jonathan Corbet: "A much quieter cycle for documentation (happily), with, one hopes, the bulk of the churn behind us. Significant stuff in this pull includes: - A set of new Chinese translations - Italian translation updates - A mechanism from Mauro to automatically format Documentation/features for the built docs - Automatic cross references without explicit :ref: markup - A new reset-controller document - An extensive new document on reporting problems from Thorsten That last patch also adds the CC-BY-4.0 license to LICENSES/dual; there was some discussion on this, but we seem to have consensus and an ack from Greg for that addition" * tag 'docs-5.11' of git://git.lwn.net/linux: (50 commits) docs: fix broken cross reference in translations/zh_CN docs: Note that sphinx 1.7 will be required soon docs: update requirements to install six module docs: reporting-issues: move 'outdated, need help' note to proper place docs: Update documentation to reflect what TAINT_CPU_OUT_OF_SPEC means docs: add a reset controller chapter to the driver API docs docs: make reporting-bugs.rst obsolete docs: Add a new text describing how to report bugs LICENSES: Add the CC-BY-4.0 license Documentation: fix multiple typos found in the admin-guide subdirectory Documentation: fix typos found in admin-guide subdirectory kernel-doc: Fix example in Nested structs/unions docs: clean up sysctl/kernel: titles, version docs: trace: fix event state structure name docs: nios2: add missing ReST file scripts: get_feat.pl: reduce table width for all features output scripts: get_feat.pl: change the group by order scripts: get_feat.pl: make complete table more coincise scripts: kernel-doc: fix parsing function-like typedefs Documentation: fix typos found in process, dev-tools, and doc-guide subdirectories ...
2020-12-14ovl: user xattrMiklos Szeredi1-2/+11
Optionally allow using "user.overlay." namespace instead of "trusted.overlay." This is necessary for overlayfs to be able to be mounted in an unprivileged namepsace. Make the option explicit, since it makes the filesystem format be incompatible. Disable redirect_dir and metacopy options, because these would allow privilege escalation through direct manipulation of the "user.overlay.redirect" or "user.overlay.metacopy" xattrs. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com>
2020-12-10file: Rename fcheck lookup_fd_rcuEric W. Biederman1-3/+3
Also remove the confusing comment about checking if a fd exists. I could not find one instance in the entire kernel that still matches the description or the reason for the name fcheck. The need for better names became apparent in the last round of discussion of this set of changes[1]. [1] https://lkml.kernel.org/r/CAHk-=wj8BQbgJFLa+J0e=iT-1qpmCRTbPAJ8gd6MJQ=kbRPqyQ@mail.gmail.com Link: https://lkml.kernel.org/r/20201120231441.29911-10-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-10file: Replace fcheck_files with files_lookup_fd_rcuEric W. Biederman1-3/+3
This change renames fcheck_files to files_lookup_fd_rcu. All of the remaining callers take the rcu_read_lock before calling this function so the _rcu suffix is appropriate. This change also tightens up the debug check to verify that all callers hold the rcu_read_lock. All callers that used to call files_check with the files->file_lock held have now been changed to call files_lookup_fd_locked. This change of name has helped remind me of which locks and which guarantees are in place helping me to catch bugs later in the patchset. The need for better names became apparent in the last round of discussion of this set of changes[1]. [1] https://lkml.kernel.org/r/CAHk-=wj8BQbgJFLa+J0e=iT-1qpmCRTbPAJ8gd6MJQ=kbRPqyQ@mail.gmail.com Link: https://lkml.kernel.org/r/20201120231441.29911-9-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-09nfsd: close cached files prior to a REMOVE or RENAME that would replace targetJeff Layton1-0/+13
It's not uncommon for some workloads to do a bunch of I/O to a file and delete it just afterward. If knfsd has a cached open file however, then the file may still be open when the dentry is unlinked. If the underlying filesystem is nfs, then that could trigger it to do a sillyrename. On a REMOVE or RENAME scan the nfsd_file cache for open files that correspond to the inode, and proactively unhash and put their references. This should prevent any delete-on-last-close activity from occurring, solely due to knfsd's open file cache. This must be done synchronously though so we use the variants that call flush_delayed_fput. There are deadlock possibilities if you call flush_delayed_fput while holding locks, however. In the case of nfsd_rename, we don't even do the lookups of the dentries to be renamed until we've locked for rename. Once we've figured out what the target dentry is for a rename, check to see whether there are cached open files associated with it. If there are, then unwind all of the locking, close them all, and then reattempt the rename. None of this is really necessary for "typical" filesystems though. It's mostly of use for NFS, so declare a new export op flag and use that to determine whether to close the files beforehand. Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09nfsd: allow filesystems to opt out of subtree checkingJeff Layton1-0/+12
When we start allowing NFS to be reexported, then we have some problems when it comes to subtree checking. In principle, we could allow it, but it would mean encoding parent info in the filehandles and there may not be enough space for that in a NFSv3 filehandle. To enforce this at export upcall time, we add a new export_ops flag that declares the filesystem ineligible for subtree checking. Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operationsJeff Layton1-0/+27
With NFSv3 nfsd will always attempt to send along WCC data to the client. This generally involves saving off the in-core inode information prior to doing the operation on the given filehandle, and then issuing a vfs_getattr to it after the op. Some filesystems (particularly clustered or networked ones) have an expensive ->getattr inode operation. Atomicity is also often difficult or impossible to guarantee on such filesystems. For those, we're best off not trying to provide WCC information to the client at all, and to simply allow it to poll for that information as needed with a GETATTR RPC. This patch adds a new flags field to struct export_operations, and defines a new EXPORT_OP_NOWCC flag that filesystems can use to indicate that nfsd should not attempt to provide WCC info in NFSv3 replies. It also adds a blurb about the new flags field and flag to the exporting documentation. The server will also now skip collecting this information for NFSv2 as well, since that info is never used there anyway. Note that this patch does not add this flag to any filesystem export_operations structures. This was originally developed to allow reexporting nfs via nfsd. Other filesystems may want to consider enabling this flag too. It's hard to tell however which ones have export operations to enable export via knfsd and which ones mostly rely on them for open-by-filehandle support, so I'm leaving that up to the individual maintainers to decide. I am cc'ing the relevant lists for those filesystems that I think may want to consider adding this though. Cc: HPDD-discuss@lists.01.org Cc: ceph-devel@vger.kernel.org Cc: cluster-devel@redhat.com Cc: fuse-devel@lists.sourceforge.net Cc: ocfs2-devel@oss.oracle.com Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>