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2019-01-24fscrypt: return -EXDEV for incompatible rename or link into encrypted dirEric Biggers1-2/+10
Currently, trying to rename or link a regular file, directory, or symlink into an encrypted directory fails with EPERM when the source file is unencrypted or is encrypted with a different encryption policy, and is on the same mountpoint. It is correct for the operation to fail, but the choice of EPERM breaks tools like 'mv' that know to copy rather than rename if they see EXDEV, but don't know what to do with EPERM. Our original motivation for EPERM was to encourage users to securely handle their data. Encrypting files by "moving" them into an encrypted directory can be insecure because the unencrypted data may remain in free space on disk, where it can later be recovered by an attacker. It's much better to encrypt the data from the start, or at least try to securely delete the source data e.g. using the 'shred' program. However, the current behavior hasn't been effective at achieving its goal because users tend to be confused, hack around it, and complain; see e.g. https://github.com/google/fscrypt/issues/76. And in some cases it's actually inconsistent or unnecessary. For example, 'mv'-ing files between differently encrypted directories doesn't work even in cases where it can be secure, such as when in userspace the same passphrase protects both directories. Yet, you *can* already 'mv' unencrypted files into an encrypted directory if the source files are on a different mountpoint, even though doing so is often insecure. There are probably better ways to teach users to securely handle their files. For example, the 'fscrypt' userspace tool could provide a command that migrates unencrypted files into an encrypted directory, acting like 'shred' on the source files and providing appropriate warnings depending on the type of the source filesystem and disk. Receiving errors on unimportant files might also force some users to disable encryption, thus making the behavior counterproductive. It's desirable to make encryption as unobtrusive as possible. Therefore, change the error code from EPERM to EXDEV so that tools looking for EXDEV will fall back to a copy. This, of course, doesn't prevent users from still doing the right things to securely manage their files. Note that this also matches the behavior when a file is renamed between two project quota hierarchies; so there's precedent for using EXDEV for things other than mountpoints. xfstests generic/398 will require an update with this change. [Rewritten from an earlier patch series by Michael Halcrow.] Cc: Michael Halcrow <mhalcrow@google.com> Cc: Joe Richey <joerichey@google.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-01-24fscrypt: remove filesystem specific build config optionChandan Rajendra1-2/+2
In order to have a common code base for fscrypt "post read" processing for all filesystems which support encryption, this commit removes filesystem specific build config option (e.g. CONFIG_EXT4_FS_ENCRYPTION) and replaces it with a build option (i.e. CONFIG_FS_ENCRYPTION) whose value affects all the filesystems making use of fscrypt. Reviewed-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-01-15Documentation/filesystems: add binderfsChristian Brauner2-0/+75
This documents the Android binderfs filesystem used to dynamically add and remove binder devices that are private to each instance. Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> [jc: tweaked markup and added to filesystems/index.rst] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-08Documentation: driver core: remove use of BUS_ATTRGreg Kroah-Hartman1-1/+3
We are getting rid of the "raw" BUS_ATTR() macro, so fix up the documentation to not refer to it anymore. Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-08Documentation/filesystems: fix title underline lengths in path-lookup.rstRandy Dunlap1-12/+12
Fix Sphinx warnings in path-lookup.rst: Documentation/filesystems/path-lookup.rst:347: WARNING: Title underline too short. Documentation/filesystems/path-lookup.rst:358: WARNING: Title underline too short. [...] Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-06Merge tag 'fscrypt_for_linus' of ↵Linus Torvalds1-77/+102
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Add Adiantum support for fscrypt" * tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: fscrypt: add Adiantum support
2019-01-06fscrypt: add Adiantum supportEric Biggers1-77/+102
Add support for the Adiantum encryption mode to fscrypt. Adiantum is a tweakable, length-preserving encryption mode with security provably reducible to that of XChaCha12 and AES-256, subject to a security bound. It's also a true wide-block mode, unlike XTS. See the paper "Adiantum: length-preserving encryption for entry-level processors" (https://eprint.iacr.org/2018/720.pdf) for more details. Also see commit 059c2a4d8e16 ("crypto: adiantum - add Adiantum support"). On sufficiently long messages, Adiantum's bottlenecks are XChaCha12 and the NH hash function. These algorithms are fast even on processors without dedicated crypto instructions. Adiantum makes it feasible to enable storage encryption on low-end mobile devices that lack AES instructions; currently such devices are unencrypted. On ARM Cortex-A7, on 4096-byte messages Adiantum encryption is about 4 times faster than AES-256-XTS encryption; decryption is about 5 times faster. In fscrypt, Adiantum is suitable for encrypting both file contents and names. With filenames, it fixes a known weakness: when two filenames in a directory share a common prefix of >= 16 bytes, with CTS-CBC their encrypted filenames share a common prefix too, leaking information. Adiantum does not have this problem. Since Adiantum also accepts long tweaks (IVs), it's also safe to use the master key directly for Adiantum encryption rather than deriving per-file keys, provided that the per-file nonce is included in the IVs and the master key isn't used for any other encryption mode. This configuration saves memory and improves performance. A new fscrypt policy flag is added to allow users to opt-in to this configuration. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-01-06Merge tag 'docs-5.0-fixes' of git://git.lwn.net/linuxLinus Torvalds2-2/+2
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes" * tag 'docs-5.0-fixes' of git://git.lwn.net/linux: doc: filesystems: fix bad references to nonexistent ext4.rst file Documentation/admin-guide: update URL of LKML information link Docs/kernel-api.rst: Remove blk-tag.c reference
2019-01-03doc: filesystems: fix bad references to nonexistent ext4.rst fileOtto Sabart2-2/+2
The ext4.rst file does not exist anymore. This patch changes all references to point to the whole ext4 directory. Fixes: d3091215921b ("docs: move ext4 administrative docs to admin-guide/") Signed-off-by: Otto Sabart <ottosabart@seberm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-02Merge tag '4.21-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds1-6/+20
Pull cifs updates from Steve French: - four fixes for stable - improvements to DFS including allowing failover to alternate targets - some small performance improvements * tag '4.21-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (39 commits) cifs: update internal module version number cifs: we can not use small padding iovs together with encryption cifs: Minor Kconfig clarification cifs: Always resolve hostname before reconnecting cifs: Add support for failover in cifs_reconnect_tcon() cifs: Add support for failover in smb2_reconnect() cifs: Only free DFS target list if we actually got one cifs: start DFS cache refresher in cifs_mount() cifs: Use GFP_ATOMIC when a lock is held in cifs_mount() cifs: Add support for failover in cifs_reconnect() cifs: Add support for failover in cifs_mount() cifs: remove set but not used variable 'sep' cifs: Make use of DFS cache to get new DFS referrals cifs: minor updates to documentation cifs: check kzalloc return cifs: remove set but not used variable 'server' cifs: Use kzfree() to free password cifs: Fix to use kmem_cache_free() instead of kfree() cifs: update for current_kernel_time64() removal cifs: Add DFS cache routines ...
2018-12-29Merge tag 'docs-5.0' of git://git.lwn.net/linuxLinus Torvalds13-445/+526
Pull documentation update from Jonathan Corbet: "A fairly normal cycle for documentation stuff. We have a new document on perf security, more Italian translations, more improvements to the memory-management docs, improvements to the pathname lookup documentation, and the usual array of smaller fixes. As is often the case, there are a few reaches outside of Documentation/ to adjust kerneldoc comments" * tag 'docs-5.0' of git://git.lwn.net/linux: (38 commits) docs: improve pathname-lookup document structure configfs: fix wrong name of struct in documentation docs/mm-api: link slab_common.c to "The Slab Cache" section slab: make kmem_cache_create{_usercopy} description proper kernel-doc doc:process: add links where missing docs/core-api: make mm-api.rst more structured x86, boot: documentation whitespace fixup Documentation: devres: note checking needs when converting doc:it: add some process/* translations doc:it: fixes in process/1.Intro Documentation: convert path-lookup from markdown to resturctured text Documentation/admin-guide: update admin-guide index.rst Documentation/admin-guide: introduce perf-security.rst file scripts/kernel-doc: Fix struct and struct field attribute processing Documentation: dev-tools: Fix typos in index.rst Correct gen_init_cpio tool's documentation Document /proc/pid PID reuse behavior Documentation: update path-lookup.md for parallel lookups Documentation: Use "while" instead of "whilst" dmaengine: Add mailing list address to the documentation ...
2018-12-28mm, proc: report PR_SET_THP_DISABLE in procMichal Hocko1-0/+3
David Rientjes has reported that commit 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active") has changed the way how we report THPable VMAs to the userspace. Their monitoring tool is triggering false alarms on PR_SET_THP_DISABLE tasks because it considers an insufficient THP usage as a memory fragmentation resp. memory pressure issue. Before the said commit each newly created VMA inherited VM_NOHUGEPAGE flag and that got exposed to the userspace via /proc/<pid>/smaps file. This implementation had its downsides as explained in the commit message but it is true that the userspace doesn't have any means to query for the process wide THP enabled/disabled status. PR_SET_THP_DISABLE is a process wide flag so it makes a lot of sense to export in the process wide context rather than per-vma. Introduce a new field to /proc/<pid>/status which export this status. If PR_SET_THP_DISABLE is used then it reports false same as when the THP is not compiled in. It doesn't consider the global THP status because we already export that information via sysfs Link: http://lkml.kernel.org/r/20181211143641.3503-4-mhocko@kernel.org Fixes: 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active") Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: David Rientjes <rientjes@google.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28mm, thp, proc: report THP eligibility for each vmaMichal Hocko1-0/+3
Userspace falls short when trying to find out whether a specific memory range is eligible for THP. There are usecases that would like to know that http://lkml.kernel.org/r/alpine.DEB.2.21.1809251248450.50347@chino.kir.corp.google.com : This is used to identify heap mappings that should be able to fault thp : but do not, and they normally point to a low-on-memory or fragmentation : issue. The only way to deduce this now is to query for hg resp. nh flags and confronting the state with the global setting. Except that there is also PR_SET_THP_DISABLE that might change the picture. So the final logic is not trivial. Moreover the eligibility of the vma depends on the type of VMA as well. In the past we have supported only anononymous memory VMAs but things have changed and shmem based vmas are supported as well these days and the query logic gets even more complicated because the eligibility depends on the mount option and another global configuration knob. Simplify the current state and report the THP eligibility in /proc/<pid>/smaps for each existing vma. Reuse transparent_hugepage_enabled for this purpose. The original implementation of this function assumes that the caller knows that the vma itself is supported for THP so make the core checks into __transparent_hugepage_enabled and use it for existing callers. __show_smap just use the new transparent_hugepage_enabled which also checks the vma support status (please note that this one has to be out of line due to include dependency issues). [mhocko@kernel.org: fix oops with NULL ->f_mapping] Link: http://lkml.kernel.org/r/20181224185106.GC16738@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20181211143641.3503-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28mm, proc: be more verbose about unstable VMA flags in /proc/<pid>/smapsMichal Hocko1-1/+3
Patch series "THP eligibility reporting via proc". This series of three patches aims at making THP eligibility reporting much more robust and long term sustainable. The trigger for the change is a regression report [2] and the long follow up discussion. In short the specific application didn't have good API to query whether a particular mapping can be backed by THP so it has used VMA flags to workaround that. These flags represent a deep internal state of VMAs and as such they should be used by userspace with a great deal of caution. A similar has happened for [3] when users complained that VM_MIXEDMAP is no longer set on DAX mappings. Again a lack of a proper API led to an abuse. The first patch in the series tries to emphasise that that the semantic of flags might change and any application consuming those should be really careful. The remaining two patches provide a more suitable interface to address [2] and provide a consistent API to query the THP status both for each VMA and process wide as well. [1] http://lkml.kernel.org/r/20181120103515.25280-1-mhocko@kernel.org [2] http://lkml.kernel.org/r/http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com [3] http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz This patch (of 3): Even though vma flags exported via /proc/<pid>/smaps are explicitly documented to be not guaranteed for future compatibility the warning doesn't go far enough because it doesn't mention semantic changes to those flags. And they are important as well because these flags are a deep implementation internal to the MM code and the semantic might change at any time. Let's consider two recent examples: http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz : commit e1fb4a086495 "dax: remove VM_MIXEDMAP for fsdax and device dax" has : removed VM_MIXEDMAP flag from DAX VMAs. Now our testing shows that in the : mean time certain customer of ours started poking into /proc/<pid>/smaps : and looks at VMA flags there and if VM_MIXEDMAP is missing among the VMA : flags, the application just fails to start complaining that DAX support is : missing in the kernel. http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com : Commit 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active") : introduced a regression in that userspace cannot always determine the set : of vmas where thp is ineligible. : Userspace relies on the "nh" flag being emitted as part of /proc/pid/smaps : to determine if a vma is eligible to be backed by hugepages. : Previous to this commit, prctl(PR_SET_THP_DISABLE, 1) would cause thp to : be disabled and emit "nh" as a flag for the corresponding vmas as part of : /proc/pid/smaps. After the commit, thp is disabled by means of an mm : flag and "nh" is not emitted. : This causes smaps parsing libraries to assume a vma is eligible for thp : and ends up puzzling the user on why its memory is not backed by thp. In both cases userspace was relying on a semantic of a specific VMA flag. The primary reason why that happened is a lack of a proper interface. While this has been worked on and it will be fixed properly, it seems that our wording could see some refinement and be more vocal about semantic aspect of these flags as well. Link: http://lkml.kernel.org/r/20181211143641.3503-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28cifs: minor updates to documentationSteve French1-6/+20
Update cifs "TODO" file. Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-20docs: improve pathname-lookup document structureNeilBrown2-17/+12
Get rid of some unneeded structural elements around the new (to RST) pathname-lookup document. Signed-off-by: NeilBrown <neilb@suse.com> [ jc: grabbed from email and changelog added ] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-12-20configfs: fix wrong name of struct in documentationHelen Koike1-1/+1
The name of the struct is configfs_bin_attribute instead of configfs_attribute Signed-off-by: Helen Koike <helen.koike@collabora.com> Fixes: 03607ace807b ("configfs: implement binary attributes") Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-12-06Documentation: convert path-lookup from markdown to resturctured textNeilBrown2-436/+464
This allows the document to be integrated with the main documentation tree. Changes include: - rename from .md to .rst - use `` for code, not single ` - use correct sub-section marking - fix indented blocks, both code and non-code - fix external-link markup Signed-off-by: NeilBrown <neilb@suse.com> [jc: changed the toctree organization a bit] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20Document /proc/pid PID reuse behaviorDaniel Colascione1-0/+7
State explicitly that holding a /proc/pid file descriptor open does not reserve the PID. Also note that in the event of PID reuse, these open file descriptors refer to the old, now-dead process, and not the new one that happens to be named the same numeric PID. Signed-off-by: Daniel Colascione <dancol@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20Documentation: update path-lookup.md for parallel lookupsNeilBrown1-19/+66
Since this document was written, i_mutex has been replace with i_rwsem, and shared locks are utilized to allow lookups in the one directory to happen in parallel. So replace i_mutex with i_rwsem, and explain how this is used for parallel lookups. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20Documentation: Use "while" instead of "whilst"Will Deacon8-10/+10
Whilst making an unrelated change to some Documentation, Linus sayeth: | Afaik, even in Britain, "whilst" is unusual and considered more | formal, and "while" is the common word. | | [...] | | Can we just admit that we work with computers, and we don't need to | use þe eald Englisc spelling of words that most of the world never | uses? dictionary.com refers to the word as "Chiefly British", which is probably an undesirable attribute for technical documentation. Replace all occurrences under Documentation/ with "while". Cc: David Howells <dhowells@redhat.com> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-08Documentation: fix spelling mistake, EACCESS -> EACCESColin Ian King1-1/+1
Trivial fix to a spelling mistake of the error access name EACCESS, rename to EACCES Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-08Documentation/proc.txt: Add 2 missing fields for /proc/<pid>/statusWaiman Long1-1/+5
It was found that two of the fields in the /proc/<pid>/status file were missing - CapAmb & Speculation_Store_Bypass. They are now added to the proc.txt documentation file. v2: Update the example as well. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-05Merge tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifsLinus Torvalds2-0/+433
Pull UBIFS updates from Richard Weinberger: - Full filesystem authentication feature, UBIFS is now able to have the whole filesystem structure authenticated plus user data encrypted and authenticated. - Minor cleanups * tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifs: (26 commits) ubifs: Remove unneeded semicolon Documentation: ubifs: Add authentication whitepaper ubifs: Enable authentication support ubifs: Do not update inode size in-place in authenticated mode ubifs: Add hashes and HMACs to default filesystem ubifs: authentication: Authenticate super block node ubifs: Create hash for default LPT ubfis: authentication: Authenticate master node ubifs: authentication: Authenticate LPT ubifs: Authenticate replayed journal ubifs: Add auth nodes to garbage collector journal head ubifs: Add authentication nodes to journal ubifs: authentication: Add hashes to index nodes ubifs: Add hashes to the tree node cache ubifs: Create functions to embed a HMAC in a node ubifs: Add helper functions for authentication support ubifs: Add separate functions to init/crc a node ubifs: Format changes for authentication support ubifs: Store read superblock node ubifs: Drop write_node ...
2018-11-02Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2-7/+20
Pull vfs dedup fixes from Dave Chinner: "This reworks the vfs data cloning infrastructure. We discovered many issues with these interfaces late in the 4.19 cycle - the worst of them (data corruption, setuid stripping) were fixed for XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all the problems was needed. That rework is the contents of this pull request. Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use a common .remap_file_range method and supply generic bounds and sanity checking functions that are shared with the data write path. The current VFS infrastructure has problems with rlimit, LFS file sizes, file time stamps, maximum filesystem file sizes, stripping setuid bits, etc and so they are addressed in these commits. We also introduce the ability for the ->remap_file_range methods to return short clones so that clones for vfs_copy_file_range() don't get rejected if the entire range can't be cloned. It also allows filesystems to sliently skip deduplication of partial EOF blocks if they are not capable of doing so without requiring errors to be thrown to userspace. Existing filesystems are converted to user the new remap_file_range method, and both XFS and ocfs2 are modified to make use of the new generic checking infrastructure" * tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits) xfs: remove [cm]time update from reflink calls xfs: remove xfs_reflink_remap_range xfs: remove redundant remap partial EOF block checks xfs: support returning partial reflink results xfs: clean up xfs_reflink_remap_blocks call site xfs: fix pagecache truncation prior to reflink ocfs2: remove ocfs2_reflink_remap_range ocfs2: support partial clone range and dedupe range ocfs2: fix pagecache truncation prior to reflink ocfs2: truncate page cache for clone destination file before remapping vfs: clean up generic_remap_file_range_prep return value vfs: hide file range comparison function vfs: enable remap callers that can handle short operations vfs: plumb remap flags through the vfs dedupe functions vfs: plumb remap flags through the vfs clone functions vfs: make remap_file_range functions take and return bytes completed vfs: remap helper should update destination inode metadata vfs: pass remap flags to generic_remap_checks vfs: pass remap flags to generic_remap_file_range_prep vfs: combine the clone and dedupe into a single remap_file_range ...
2018-11-02Merge tag 'ovl-update-4.20' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "A mix of fixes and cleanups" * tag 'ovl-update-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: automatically enable redirect_dir on metacopy=on ovl: check whiteout in ovl_create_over_whiteout() ovl: using posix_acl_xattr_size() to get size instead of posix_acl_to_xattr() ovl: abstract ovl_inode lock with a helper ovl: remove the 'locked' argument of ovl_nlink_{start,end} ovl: relax requirement for non null uuid of lower fs ovl: fold copy-up helpers into callers ovl: untangle copy up call chain ovl: relax permission checking on underlying layers ovl: fix recursive oi->lock in ovl_link() vfs: fix FIGETBSZ ioctl on an overlayfs file ovl: clean up error handling in ovl_get_tmpfile() ovl: fix error handling in ovl_verify_set_fh()
2018-11-01ovl: automatically enable redirect_dir on metacopy=onMiklos Szeredi1-0/+6
Current behavior is to automatically disable metacopy if redirect_dir is not enabled and proceed with the mount. If "metacopy=on" mount option was given, then this behavior can confuse the user: no mount failure, yet metacopy is disabled. This patch makes metacopy=on imply redirect_dir=on. The converse is also true: turning off full redirect with redirect_dir= {off|follow|nofollow} will disable metacopy. If both metacopy=on and redirect_dir={off|follow|nofollow} is specified, then mount will fail, since there's no way to correctly resolve the conflict. Reported-by: Daniel Walsh <dwalsh@redhat.com> Fixes: d5791044d2e5 ("ovl: Provide a mount option metacopy=on/off...") Cc: <stable@vger.kernel.org> # v4.19 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-11-01Merge tag 'ceph-for-4.20-rc1' of git://github.com/ceph/ceph-clientLinus Torvalds1-0/+5
Pull ceph updates from Ilya Dryomov: "The highlights are: - a series that fixes some old memory allocation issues in libceph (myself). We no longer allocate memory in places where allocation failures cannot be handled and BUG when the allocation fails. - support for copy_file_range() syscall (Luis Henriques). If size and alignment conditions are met, it leverages RADOS copy-from operation. Otherwise, a local copy is performed. - a patch that reduces memory requirement of ceph_sync_read() from the size of the entire read to the size of one object (Zheng Yan). - fallocate() syscall is now restricted to FALLOC_FL_PUNCH_HOLE (Luis Henriques)" * tag 'ceph-for-4.20-rc1' of git://github.com/ceph/ceph-client: (25 commits) ceph: new mount option to disable usage of copy-from op ceph: support copy_file_range file operation libceph: support the RADOS copy-from operation ceph: add non-blocking parameter to ceph_try_get_caps() libceph: check reply num_data_items in setup_request_data() libceph: preallocate message data items libceph, rbd, ceph: move ceph_osdc_alloc_messages() calls libceph: introduce alloc_watch_request() libceph: assign cookies in linger_submit() libceph: enable fallback to ceph_msg_new() in ceph_msgpool_get() ceph: num_ops is off by one in ceph_aio_retry_work() libceph: no need to call osd_req_opcode_valid() in osd_req_encode_op() ceph: set timeout conditionally in __cap_delay_requeue libceph: don't consume a ref on pagelist in ceph_msg_data_add_pagelist() libceph: introduce ceph_pagelist_alloc() libceph: osd_req_op_cls_init() doesn't need to take opcode libceph: bump CEPH_MSG_MAX_DATA_LEN ceph: only allow punch hole mode in fallocate ceph: refactor ceph_sync_read() ceph: check if LOOKUPNAME request was aborted when filling trace ...
2018-10-30Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linuxLinus Torvalds1-3/+3
Pull nfsd updates from Bruce Fields: "Olga added support for the NFSv4.2 asynchronous copy protocol. We already supported COPY, by copying a limited amount of data and then returning a short result, letting the client resend. The asynchronous protocol should offer better performance at the expense of some complexity. The other highlight is Trond's work to convert the duplicate reply cache to a red-black tree, and to move it and some other server caches to RCU. (Previously these have meant taking global spinlocks on every RPC) Otherwise, some RDMA work and miscellaneous bugfixes" * tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux: (30 commits) lockd: fix access beyond unterminated strings in prints nfsd: Fix an Oops in free_session() nfsd: correctly decrement odstate refcount in error path svcrdma: Increase the default connection credit limit svcrdma: Remove try_module_get from backchannel svcrdma: Remove ->release_rqst call in bc reply handler svcrdma: Reduce max_send_sges nfsd: fix fall-through annotations knfsd: Improve lookup performance in the duplicate reply cache using an rbtree knfsd: Further simplify the cache lookup knfsd: Simplify NFS duplicate replay cache knfsd: Remove dead code from nfsd_cache_lookup SUNRPC: Simplify TCP receive code SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock SUNRPC: Remove non-RCU protected lookup NFS: Fix up a typo in nfs_dns_ent_put NFS: Lockless DNS lookups knfsd: Lockless lookup of NFSv4 identities. SUNRPC: Lockless server RPCSEC_GSS context lookup knfsd: Allow lockless lookups of the exports ...
2018-10-30vfs: enable remap callers that can handle short operationsDarrick J. Wong1-1/+3
Plumb in a remap flag that enables the filesystem remap handler to shorten remapping requests for callers that can handle it. Now copy_file_range can report partial success (in case we run up against alignment problems, resource limits, etc.). We also enable CAN_SHORTEN for fideduperange to maintain existing userspace-visible behavior where xfs/btrfs shorten the dedupe range to avoid stale post-eof data exposure. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30vfs: make remap_file_range functions take and return bytes completedDarrick J. Wong1-5/+5
Change the remap_file_range functions to take a number of bytes to operate upon and return the number of bytes they operated on. This is a requirement for allowing fs implementations to return short clone/dedupe results to the user, which will enable us to obey resource limits in a graceful manner. A subsequent patch will enable copy_file_range to signal to the ->clone_file_range implementation that it can handle a short length, which will be returned in the function's return value. For now the short return is not implemented anywhere so the behavior won't change -- either copy_file_range manages to clone the entire range or it tries an alternative. Neither clone ioctl can take advantage of this, alas. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30vfs: combine the clone and dedupe into a single remap_file_rangeDarrick J. Wong2-7/+18
Combine the clone_file_range and dedupe_file_range operations into a single remap_file_range file operation dispatch since they're fundamentally the same operation. The differences between the two can be made in the prep functions. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-29SUNRPC: Remove non-RCU protected lookupTrond Myklebust1-3/+3
Clean up the cache code by removing the non-RCU protected lookup. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-10-29Merge tag 'staging-4.20-rc1' of ↵Linus Torvalds3-398/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging/IIO driver updates from Greg KH: "Here is the big staging and IIO driver pull request for 4.20-rc1. There are lots of things here, we ended up adding more lines than removing, thanks to a large influx of Comedi National Instrument device support. Someday soon we need to get comedi out of staging... Other than the comedi drivers, the "big" things here are: - new iio drivers - delete dgnc driver (no one used it and no one had the hardware anymore) - vbox driver updates and fixes - erofs fixes - tons and tons of tiny checkpatch fixes for almost all staging drivers All of these have been in linux-next, with the last few happening a bit "late" due to them getting stuck on my laptop during travel to the Mantainers summit" * tag 'staging-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (690 commits) staging: gasket: Fix sparse "incorrect type in assignment" warnings. staging: gasket: remove debug logs for callback invocation staging: gasket: remove debug logs in page table mapping calls staging: rtl8188eu: core: Use sizeof(*p) instead of sizeof(struct P) for memory allocation staging: ks7010: Remove extra blank line staging: gasket: Remove extra blank line staging: media: davinci_vpfe: Fix spelling mistake in enum staging: speakup: Add a pair of braces staging: wlan-ng: Replace long int with long staging: MAINTAINERS: remove obsolete IPX staging directory staging: MAINTAINERS: remove NCP filesystem entry staging: rtl8188eu: cleanup comparsions to false staging: gasket: Update device virtual address comment staging: gasket: sysfs: fix attribute release comment staging: gasket: apex: fix sysfs_show staging: gasket: page_table: simplify gasket_components_to_dev_address staging: gasket: page_table: fix comment in components_to_dev_address staging: gasket: page table: fixup error path allocating coherent mem staging: gasket: page_table: rearrange gasket_page_table_entry staging: gasket: page_table: remove unnecessary PTE status set to free ...
2018-10-27mm, proc: add KReclaimable to /proc/meminfoVlastimil Babka1-0/+4
The vmstat NR_KERNEL_MISC_RECLAIMABLE counter is for kernel non-slab allocations that can be reclaimed via shrinker. In /proc/meminfo, we can show the sum of all reclaimable kernel allocations (including slab) as "KReclaimable". Add the same counter also to per-node meminfo under /sys With this counter, users will have more complete information about kernel memory usage. Non-slab reclaimable pages (currently just the ION allocator) will not be missing from /proc/meminfo, making users wonder where part of their memory went. More precisely, they already appear in MemAvailable, but without the new counter, it's not obvious why the value in MemAvailable doesn't fully correspond with the sum of other counters participating in it. Link: http://lkml.kernel.org/r/20180731090649.16028-6-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26Merge branch 'linus' of ↵Linus Torvalds1-10/+0
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Remove VLA usage - Add cryptostat user-space interface - Add notifier for new crypto algorithms Algorithms: - Add OFB mode - Remove speck Drivers: - Remove x86/sha*-mb as they are buggy - Remove pcbc(aes) from x86/aesni - Improve performance of arm/ghash-ce by up to 85% - Implement CTS-CBC in arm64/aes-blk, faster by up to 50% - Remove PMULL based arm64/crc32 driver - Use PMULL in arm64/crct10dif - Add aes-ctr support in s5p-sss - Add caam/qi2 driver Others: - Pick better transform if one becomes available in crc-t10dif" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (124 commits) crypto: chelsio - Update ntx queue received from cxgb4 crypto: ccree - avoid implicit enum conversion crypto: caam - add SPDX license identifier to all files crypto: caam/qi - simplify CGR allocation, freeing crypto: mxs-dcp - make symbols 'sha1_null_hash' and 'sha256_null_hash' static crypto: arm64/aes-blk - ensure XTS mask is always loaded crypto: testmgr - fix sizeof() on COMP_BUF_SIZE crypto: chtls - remove set but not used variable 'csk' crypto: axis - fix platform_no_drv_owner.cocci warnings crypto: x86/aes-ni - fix build error following fpu template removal crypto: arm64/aes - fix handling sub-block CTS-CBC inputs crypto: caam/qi2 - avoid double export crypto: mxs-dcp - Fix AES issues crypto: mxs-dcp - Fix SHA null hashes and output length crypto: mxs-dcp - Implement sha import/export crypto: aegis/generic - fix for big endian systems crypto: morus/generic - fix for big endian systems crypto: lrw - fix rebase error after out of bounds fix crypto: cavium/nitrox - use pci_alloc_irq_vectors() while enabling MSI-X. crypto: cavium/nitrox - NITROX command queue changes. ...
2018-10-25Merge branch 'work.lookup' of ↵Linus Torvalds1-0/+11
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more ->lookup() cleanups from Al Viro: "Some ->lookup() instances are still overcomplicating the life for themselves, open-coding the stuff that would be handled by d_splice_alias() just fine. Simplify a couple of such cases caught this cycle and document d_splice_alias() intended use" * 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Document d_splice_alias() calling conventions for ->lookup() users. simplify btrfs_lookup() clean erofs_lookup()
2018-10-24Merge tag 'docs-4.20' of git://git.lwn.net/linuxLinus Torvalds4-181/+2
Pull documentation updates from Jonathan Corbet: "This is a fairly typical cycle for documentation. There's some welcome readability improvements for the formatted output, some LICENSES updates including the addition of the ISC license, the removal of the unloved and unmaintained 00-INDEX files, the deprecated APIs document from Kees, more MM docs from Mike Rapoport, and the usual pile of typo fixes and corrections" * tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits) docs: Fix typos in histogram.rst docs: Introduce deprecated APIs list kernel-doc: fix declaration type determination doc: fix a typo in adding-syscalls.rst docs/admin-guide: memory-hotplug: remove table of contents doc: printk-formats: Remove bogus kobject references for device nodes Documentation: preempt-locking: Use better example dm flakey: Document "error_writes" feature docs/completion.txt: Fix a couple of punctuation nits LICENSES: Add ISC license text LICENSES: Add note to CDDL-1.0 license that it should not be used docs/core-api: memory-hotplug: add some details about locking internals docs/core-api: rename memory-hotplug-notifier to memory-hotplug docs: improve readability for people with poorer eyesight yama: clarify ptrace_scope=2 in Yama documentation docs/vm: split memory hotplug notifier description to Documentation/core-api docs: move memory hotplug description into admin-guide/mm doc: Fix acronym "FEKEK" in ecryptfs docs: fix some broken documentation references iommu: Fix passthrough option documentation ...
2018-10-24Merge tag 'ext4_for_linus' of ↵Linus Torvalds25-692/+68
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: - further restructure ext4 documentation - fix up ext4's delayed allocation for bigalloc file systems - fix up some syzbot-detected races in EXT4_IOC_MOVE_EXT, EXT4_IOC_SWAP_BOOT, and ext4_remount - ... and a few other miscellaneous bugs and optimizations. * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits) ext4: fix use-after-free race in ext4_remount()'s error path ext4: cache NULL when both default_acl and acl are NULL docs: promote the ext4 data structures book to top level docs: move ext4 administrative docs to admin-guide/ jbd2: fix use after free in jbd2_log_do_checkpoint() ext4: propagate error from dquot_initialize() in EXT4_IOC_FSSETXATTR ext4: fix setattr project check in fssetxattr ioctl docs: make ext4 readme tables readable docs: fix ext4 documentation table formatting problems docs: generate a separate ext4 pdf file from the documentation ext4: convert fault handler to use vm_fault_t type ext4: initialize retries variable in ext4_da_write_inline_data_begin() ext4: fix EXT4_IOC_SWAP_BOOT ext4: fix build error when DX_DEBUG is defined ext4: fix argument checking in EXT4_IOC_MOVE_EXT ext4: fix reserved cluster accounting at page invalidation time ext4: adjust reserved cluster count when removing extents ext4: reduce reserved cluster count by number of allocated clusters ext4: fix reserved cluster accounting at delayed write time ext4: add new pending reservation mechanism ...
2018-10-24Merge tag 'f2fs-for-4.20-rc1' of ↵Linus Torvalds1-1/+7
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "In this round, we've added 1) superblock checksum feature, 2) implemented new mount option which we can disable/enable checkpoint to provide atomic updates of entire filesystem, 3) refactored quota operations to enhance its consistency along with checkpoint, 4) fixed subtle IO hang conditions and roll-forward recovery flow to resurrect any fsync'ed inode metadata. Enhancements: - add checksum to keep superblock contents more safe - add checkpoint=disable/enable to support A/B update of entire filesystem - use plug for readahead IO in readdir - add more IO counts to avoid block layer hacks Bug fixes: - prevent data corruption issue for hardware encryption - fix IO hang issues when GC is heavily triggered - add missing up_read in __write_node_page - recover inode metadata during roll-forward recovery flow - fix null pointer dereference issue in wrongly configured discard map There are some more sanity checks and minor bug fixes as well" * tag 'f2fs-for-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (62 commits) f2fs: fix to keep project quota consistent f2fs: guarantee journalled quota data by checkpoint f2fs: cleanup dirty pages if recover failed f2fs: fix data corruption issue with hardware encryption f2fs: fix to recover inode->i_flags of inode block during POR f2fs: spread f2fs_set_inode_flags() f2fs: fix to spread clear_cold_data() Revert "f2fs: fix to clear PG_checked flag in set_page_dirty()" f2fs: account read IOs and use IO counts for is_idle f2fs: fix to account IO correctly for cgroup writeback f2fs: fix to account IO correctly f2fs: remove request_list check in is_idle() f2fs: allow to mount, if quota is failed f2fs: update REQ_TIME in f2fs_cross_rename() f2fs: do not update REQ_TIME in case of error conditions f2fs: remove unneeded disable_nat_bits() f2fs: remove unused sbi->trigger_ssr_threshold f2fs: shrink sbi->sb_lock coverage in set_file_temperature() f2fs: use rb_*_cached friends f2fs: fix to recover cold bit of inode block during POR ...
2018-10-23Documentation: ubifs: Add authentication whitepaperSascha Hauer1-0/+426
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Enable authentication supportSascha Hauer1-0/+7
With the preparations all being done this patch now enables authentication support for UBIFS. Authentication is enabled when the newly introduced auth_key and auth_hash_name mount options are passed. auth_key provides the key which is used for authentication whereas auth_hash_name provides the hashing algorithm used for this FS. Passing these options make authentication mandatory and only UBIFS images that can be authenticated with the given key are allowed. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-22ceph: new mount option to disable usage of copy-from opLuis Henriques1-0/+5
Add a new mount option 'nocopyfrom' that will prevent the usage of the RADOS 'copy-from' operation in cephfs. This could be useful, for example, for an administrator to temporarily mitigate any possible bugs in the 'copy-from' implementation. Currently, only copy_file_range uses this RADOS operation. Setting this mount option will result in this syscall reverting to the default VFS implementation, i.e. to perform the copies locally instead of doing remote object copies. Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2018-10-16f2fs: checkpoint disablingDaniel Rosenberg1-0/+5
Note that, it requires "f2fs: return correct errno in f2fs_gc". This adds a lightweight non-persistent snapshotting scheme to f2fs. To use, mount with the option checkpoint=disable, and to return to normal operation, remount with checkpoint=enable. If the filesystem is shut down before remounting with checkpoint=enable, it will revert back to its apparent state when it was first mounted with checkpoint=disable. This is useful for situations where you wish to be able to roll back the state of the disk in case of some critical failure. Signed-off-by: Daniel Rosenberg <drosen@google.com> [Jaegeuk Kim: use SB_RDONLY instead of MS_RDONLY] Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-10-10Document d_splice_alias() calling conventions for ->lookup() users.Al Viro1-0/+11
Short version: it does the right thing when given NULL or ERR_PTR(...) and its calling conventions are chosen to have minimal PITA when used in ->lookup() instances. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-06docs: promote the ext4 data structures book to top levelDarrick J. Wong24-19/+8
Move the ext4 data structures book to Documentation/filesystems/ext4/ since the administrative information moved elsewhere. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-10-06docs: move ext4 administrative docs to admin-guide/Darrick J. Wong2-575/+0
Move the ext4 mount option and other administrative stuff to the Linux administrator's guide. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-10-03docs: make ext4 readme tables readableDarrick J. Wong1-430/+391
The tables in the ext4 readme are not particularly space efficient in the text or html outputs, and they're totally broken in the pdf output. Convert them into titled paragraphs so that they render more nicely. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-10-03docs: fix ext4 documentation table formatting problemsDarrick J. Wong10-59/+60
It turns out that the latex table formatters lay out table columns with the exact proportional widths given in the table metadata, even if text overflows outside the box. This was not caught during the initial import because the HTML renderers are smart enough to fudge the table. Fix the table column width formatting problems in the data structures and algorithms documentation so that we don't have squashed columns. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-09-20docs: fix some broken documentation referencesMauro Carvalho Chehab2-2/+2
Some documentation files received recent changes and are pointing to wrong places. Those references can easily fixed with the help of a script: $ ./scripts/documentation-file-ref-check --fix Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>