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* Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linuxLinus Torvalds2023-10-301-9/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull fscrypt updates from Eric Biggers: "This update adds support for configuring the crypto data unit size (i.e. the granularity of file contents encryption) to be less than the filesystem block size. This can allow users to use inline encryption hardware in some cases when it wouldn't otherwise be possible. In addition, there are two commits that are prerequisites for the extent-based encryption support that the btrfs folks are working on" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: fscrypt: track master key presence separately from secret fscrypt: rename fscrypt_info => fscrypt_inode_info fscrypt: support crypto data unit size less than filesystem block size fscrypt: replace get_ino_and_lblk_bits with just has_32bit_inodes fscrypt: compute max_lblk_bits from s_maxbytes and block size fscrypt: make the bounce page pool opt-in instead of opt-out fscrypt: make it clearer that key_prefix is deprecated
| * fscrypt: support crypto data unit size less than filesystem block sizeEric Biggers2023-09-251-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now, fscrypt has always used the filesystem block size as the granularity of file contents encryption. Two scenarios have come up where a sub-block granularity of contents encryption would be useful: 1. Inline crypto hardware that only supports a crypto data unit size that is less than the filesystem block size. 2. Support for direct I/O at a granularity less than the filesystem block size, for example at the block device's logical block size in order to match the traditional direct I/O alignment requirement. (1) first came up with older eMMC inline crypto hardware that only supports a crypto data unit size of 512 bytes. That specific case ultimately went away because all systems with that hardware continued using out of tree code and never actually upgraded to the upstream inline crypto framework. But, now it's coming back in a new way: some current UFS controllers only support a data unit size of 4096 bytes, and there is a proposal to increase the filesystem block size to 16K. (2) was discussed as a "nice to have" feature, though not essential, when support for direct I/O on encrypted files was being upstreamed. Still, the fact that this feature has come up several times does suggest it would be wise to have available. Therefore, this patch implements it by using one of the reserved bytes in fscrypt_policy_v2 to allow users to select a sub-block data unit size. Supported data unit sizes are powers of 2 between 512 and the filesystem block size, inclusively. Support is implemented for both the FS-layer and inline crypto cases. This patch focuses on the basic support for sub-block data units. Some things are out of scope for this patch but may be addressed later: - Supporting sub-block data units in combination with FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64, in most cases. Unfortunately this combination usually causes data unit indices to exceed 32 bits, and thus fscrypt_supported_policy() correctly disallows it. The users who potentially need this combination are using f2fs. To support it, f2fs would need to provide an option to slightly reduce its max file size. - Supporting sub-block data units in combination with FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32. This has the same problem described above, but also it will need special code to make DUN wraparound still happen on a FS block boundary. - Supporting use case (2) mentioned above. The encrypted direct I/O code will need to stop requiring and assuming FS block alignment. This won't be hard, but it belongs in a separate patch. - Supporting this feature on filesystems other than ext4 and f2fs. (Filesystems declare support for it via their fscrypt_operations.) On UBIFS, sub-block data units don't make sense because UBIFS encrypts variable-length blocks as a result of compression. CephFS could support it, but a bit more work would be needed to make the fscrypt_*_block_inplace functions play nicely with sub-block data units. I don't think there's a use case for this on CephFS anyway. Link: https://lore.kernel.org/r/20230925055451.59499-6-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
| * fscrypt: replace get_ino_and_lblk_bits with just has_32bit_inodesEric Biggers2023-09-251-8/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that fs/crypto/ computes the filesystem's lblk_bits from its maximum file size, it is no longer necessary for filesystems to provide lblk_bits via fscrypt_operations::get_ino_and_lblk_bits. It is still necessary for fs/crypto/ to retrieve ino_bits from the filesystem. However, this is used only to decide whether inode numbers fit in 32 bits. Also, ino_bits is static for all relevant filesystems, i.e. it doesn't depend on the filesystem instance. Therefore, in the interest of keeping things as simple as possible, replace 'get_ino_and_lblk_bits' with a flag 'has_32bit_inodes'. This can always be changed back to a function if a filesystem needs it to be dynamic, but for now a static flag is all that's needed. Link: https://lore.kernel.org/r/20230925055451.59499-5-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
| * fscrypt: make the bounce page pool opt-in instead of opt-outEric Biggers2023-09-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace FS_CFLG_OWN_PAGES with a bit flag 'needs_bounce_pages' which has the opposite meaning. I.e., filesystems now opt into the bounce page pool instead of opt out. Make fscrypt_alloc_bounce_page() check that the bounce page pool has been initialized. I believe the opt-in makes more sense, since nothing else in fscrypt_operations is opt-out, and these days filesystems can choose to use blk-crypto which doesn't need the fscrypt bounce page pool. Also, I happen to be planning to add two more flags, and I wanted to fix the "FS_CFLG_" name anyway as it wasn't prefixed with "FSCRYPT_". Link: https://lore.kernel.org/r/20230925055451.59499-3-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
| * fscrypt: make it clearer that key_prefix is deprecatedEric Biggers2023-09-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | fscrypt_operations::key_prefix should not be set by any filesystems that aren't setting it already. This is already documented, but apparently it's not sufficiently clear, as both ceph and btrfs have tried to set it. Rename the field to legacy_key_prefix and improve the documentation to hopefully make it clearer. Link: https://lore.kernel.org/r/20230925055451.59499-2-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
* | Merge tag 'vfs-6.7.ctime' of ↵Linus Torvalds2023-10-309-35/+56
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull vfs inode time accessor updates from Christian Brauner: "This finishes the conversion of all inode time fields to accessor functions as discussed on list. Changing timestamps manually as we used to do before is error prone. Using accessors function makes this robust. It does not contain the switch of the time fields to discrete 64 bit integers to replace struct timespec and free up space in struct inode. But after this, the switch can be trivially made and the patch should only affect the vfs if we decide to do it" * tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (86 commits) fs: rename inode i_atime and i_mtime fields security: convert to new timestamp accessors selinux: convert to new timestamp accessors apparmor: convert to new timestamp accessors sunrpc: convert to new timestamp accessors mm: convert to new timestamp accessors bpf: convert to new timestamp accessors ipc: convert to new timestamp accessors linux: convert to new timestamp accessors zonefs: convert to new timestamp accessors xfs: convert to new timestamp accessors vboxsf: convert to new timestamp accessors ufs: convert to new timestamp accessors udf: convert to new timestamp accessors ubifs: convert to new timestamp accessors tracefs: convert to new timestamp accessors sysv: convert to new timestamp accessors squashfs: convert to new timestamp accessors server: convert to new timestamp accessors client: convert to new timestamp accessors ...
| * | ext4: convert to new timestamp accessorsJeff Layton2023-10-189-35/+56
| |/ | | | | | | | | | | | | | | Convert to using the new inode timestamp accessor functions. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://lore.kernel.org/r/20231004185347.80880-33-jlayton@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* | Merge tag 'vfs-6.7.xattr' of ↵Linus Torvalds2023-10-302-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull vfs xattr updates from Christian Brauner: "The 's_xattr' field of 'struct super_block' currently requires a mutable table of 'struct xattr_handler' entries (although each handler itself is const). However, no code in vfs actually modifies the tables. This changes the type of 's_xattr' to allow const tables, and modifies existing file systems to move their tables to .rodata. This is desirable because these tables contain entries with function pointers in them; moving them to .rodata makes it considerably less likely to be modified accidentally or maliciously at runtime" * tag 'vfs-6.7.xattr' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (30 commits) const_structs.checkpatch: add xattr_handler net: move sockfs_xattr_handlers to .rodata shmem: move shmem_xattr_handlers to .rodata overlayfs: move xattr tables to .rodata xfs: move xfs_xattr_handlers to .rodata ubifs: move ubifs_xattr_handlers to .rodata squashfs: move squashfs_xattr_handlers to .rodata smb: move cifs_xattr_handlers to .rodata reiserfs: move reiserfs_xattr_handlers to .rodata orangefs: move orangefs_xattr_handlers to .rodata ocfs2: move ocfs2_xattr_handlers and ocfs2_xattr_handler_map to .rodata ntfs3: move ntfs_xattr_handlers to .rodata nfs: move nfs4_xattr_handlers to .rodata kernfs: move kernfs_xattr_handlers to .rodata jfs: move jfs_xattr_handlers to .rodata jffs2: move jffs2_xattr_handlers to .rodata hfsplus: move hfsplus_xattr_handlers to .rodata hfs: move hfs_xattr_handlers to .rodata gfs2: move gfs2_xattr_handlers_max to .rodata fuse: move fuse_xattr_handlers to .rodata ...
| * | ext4: move ext4_xattr_handlers to .rodataWedson Almeida Filho2023-10-092-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes it harder for accidental or malicious changes to ext4_xattr_handlers at runtime. Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: linux-ext4@vger.kernel.org Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com> Link: https://lore.kernel.org/r/20230930050033.41174-3-wedsonaf@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
* | | ext4: Convert to bdev_open_by_dev()Jan Kara2023-10-283-30/+33
| |/ |/| | | | | | | | | | | | | | | | | | | | | Convert ext4 to use bdev_open_by_dev() and pass the handle around. CC: linux-ext4@vger.kernel.org CC: Ted Tso <tytso@mit.edu> Acked-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230927093442.25915-22-jack@suse.cz Signed-off-by: Christian Brauner <brauner@kernel.org>
* | Revert "ext4: switch to multigrain timestamps"Christian Brauner2023-09-201-1/+1
|/ | | | | | | | | | | | | | This reverts commit 0269b585868e59b6a2ecc6ea685d39310e4fc18b. Users reported regressions due to enabling multi-grained timestamps unconditionally. As no clear consensus on a solution has come up and the discussion has gone back to the drawing board revert the infrastructure changes for. If it isn't code that's here to stay, make it go away. Message-ID: <20230920-keine-eile-c9755b5825db@brauner> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
* Merge tag 'ext4_for_linus-6.6-rc2' of ↵Linus Torvalds2023-09-172-32/+48
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Regression and bug fixes for ext4" * tag 'ext4_for_linus-6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix rec_len verify error ext4: do not let fstrim block system suspend ext4: move setting of trimmed bit into ext4_try_to_trim_range() jbd2: Fix memory leak in journal_init_common() jbd2: Remove page size assumptions buffer: Make bh_offset() work for compound pages
| * ext4: fix rec_len verify errorShida Zhang2023-09-141-11/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the configuration PAGE_SIZE 64k and filesystem blocksize 64k, a problem occurred when more than 13 million files were directly created under a directory: EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt? Run e2fsck -D. EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt? Run e2fsck -D. EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum When enough files are created, the fake_dirent->reclen will be 0xffff. it doesn't equal to the blocksize 65536, i.e. 0x10000. But it is not the same condition when blocksize equals to 4k. when enough files are created, the fake_dirent->reclen will be 0x1000. it equals to the blocksize 4k, i.e. 0x1000. The problem seems to be related to the limitation of the 16-bit field when the blocksize is set to 64k. To address this, helpers like ext4_rec_len_{from,to}_disk has already been introduced to complete the conversion between the encoded and the plain form of rec_len. So fix this one by using the helper, and all the other in this file too. Cc: stable@kernel.org Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes") Suggested-by: Andreas Dilger <adilger@dilger.ca> Suggested-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: do not let fstrim block system suspendJan Kara2023-09-141-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Len Brown has reported that system suspend sometimes fail due to inability to freeze a task working in ext4_trim_fs() for one minute. Trimming a large filesystem on a disk that slowly processes discard requests can indeed take a long time. Since discard is just an advisory call, it is perfectly fine to interrupt it at any time and the return number of discarded blocks until that moment. Do that when we detect the task is being frozen. Cc: stable@kernel.org Reported-by: Len Brown <lenb@kernel.org> Suggested-by: Dave Chinner <david@fromorbit.com> References: https://bugzilla.kernel.org/show_bug.cgi?id=216322 Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230913150504.9054-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: move setting of trimmed bit into ext4_try_to_trim_range()Jan Kara2023-09-141-21/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we set the group's trimmed bit in ext4_trim_all_free() based on return value of ext4_try_to_trim_range(). However when we will want to abort trimming because of suspend attempt, we want to return success from ext4_try_to_trim_range() but not set the trimmed bit. Instead implementing awkward propagation of this information, just move setting of trimmed bit into ext4_try_to_trim_range() when the whole group is trimmed. Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230913150504.9054-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | Merge tag 'ext4_for_linus-6.6-rc1' of ↵Linus Torvalds2023-08-3120-376/+462
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Many ext4 and jbd2 cleanups and bug fixes: - Cleanups in the ext4 remount code when going to and from read-only - Cleanups in ext4's multiblock allocator - Cleanups in the jbd2 setup/mounting code paths - Performance improvements when appending to a delayed allocation file - Miscellaneous syzbot and other bug fixes" * tag 'ext4_for_linus-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (60 commits) ext4: fix slab-use-after-free in ext4_es_insert_extent() libfs: remove redundant checks of s_encoding ext4: remove redundant checks of s_encoding ext4: reject casefold inode flag without casefold feature ext4: use LIST_HEAD() to initialize the list_head in mballoc.c ext4: do not mark inode dirty every time when appending using delalloc ext4: rename s_error_work to s_sb_upd_work ext4: add periodic superblock update check ext4: drop dio overwrite only flag and associated warning ext4: add correct group descriptors and reserved GDT blocks to system zone ext4: remove unused function declaration ext4: mballoc: avoid garbage value from err ext4: use sbi instead of EXT4_SB(sb) in ext4_mb_new_blocks_simple() ext4: change the type of blocksize in ext4_mb_init_cache() ext4: fix unttached inode after power cut with orphan file feature enabled jbd2: correct the end of the journal recovery scan range ext4: ext4_get_{dev}_journal return proper error value ext4: cleanup ext4_get_dev_journal() and ext4_get_journal() jbd2: jbd2_journal_init_{dev,inode} return proper error return value jbd2: drop useless error tag in jbd2_journal_wipe() ...
| * ext4: fix slab-use-after-free in ext4_es_insert_extent()Baokun Li2023-08-271-14/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Yikebaer reported an issue: ================================================================== BUG: KASAN: slab-use-after-free in ext4_es_insert_extent+0xc68/0xcb0 fs/ext4/extents_status.c:894 Read of size 4 at addr ffff888112ecc1a4 by task syz-executor/8438 CPU: 1 PID: 8438 Comm: syz-executor Not tainted 6.5.0-rc5 #1 Call Trace: [...] kasan_report+0xba/0xf0 mm/kasan/report.c:588 ext4_es_insert_extent+0xc68/0xcb0 fs/ext4/extents_status.c:894 ext4_map_blocks+0x92a/0x16f0 fs/ext4/inode.c:680 ext4_alloc_file_blocks.isra.0+0x2df/0xb70 fs/ext4/extents.c:4462 ext4_zero_range fs/ext4/extents.c:4622 [inline] ext4_fallocate+0x251c/0x3ce0 fs/ext4/extents.c:4721 [...] Allocated by task 8438: [...] kmem_cache_zalloc include/linux/slab.h:693 [inline] __es_alloc_extent fs/ext4/extents_status.c:469 [inline] ext4_es_insert_extent+0x672/0xcb0 fs/ext4/extents_status.c:873 ext4_map_blocks+0x92a/0x16f0 fs/ext4/inode.c:680 ext4_alloc_file_blocks.isra.0+0x2df/0xb70 fs/ext4/extents.c:4462 ext4_zero_range fs/ext4/extents.c:4622 [inline] ext4_fallocate+0x251c/0x3ce0 fs/ext4/extents.c:4721 [...] Freed by task 8438: [...] kmem_cache_free+0xec/0x490 mm/slub.c:3823 ext4_es_try_to_merge_right fs/ext4/extents_status.c:593 [inline] __es_insert_extent+0x9f4/0x1440 fs/ext4/extents_status.c:802 ext4_es_insert_extent+0x2ca/0xcb0 fs/ext4/extents_status.c:882 ext4_map_blocks+0x92a/0x16f0 fs/ext4/inode.c:680 ext4_alloc_file_blocks.isra.0+0x2df/0xb70 fs/ext4/extents.c:4462 ext4_zero_range fs/ext4/extents.c:4622 [inline] ext4_fallocate+0x251c/0x3ce0 fs/ext4/extents.c:4721 [...] ================================================================== The flow of issue triggering is as follows: 1. remove es raw es es removed es1 |-------------------| -> |----|.......|------| 2. insert es es insert es1 merge with es es1 merge with es and free es1 |----|.......|------| -> |------------|------| -> |-------------------| es merges with newes, then merges with es1, frees es1, then determines if es1->es_len is 0 and triggers a UAF. The code flow is as follows: ext4_es_insert_extent es1 = __es_alloc_extent(true); es2 = __es_alloc_extent(true); __es_remove_extent(inode, lblk, end, NULL, es1) __es_insert_extent(inode, &newes, es1) ---> insert es1 to es tree __es_insert_extent(inode, &newes, es2) ext4_es_try_to_merge_right ext4_es_free_extent(inode, es1) ---> es1 is freed if (es1 && !es1->es_len) // Trigger UAF by determining if es1 is used. We determine whether es1 or es2 is used immediately after calling __es_remove_extent() or __es_insert_extent() to avoid triggering a UAF if es1 or es2 is freed. Reported-by: Yikebaer Aizezi <yikebaer61@gmail.com> Closes: https://lore.kernel.org/lkml/CALcu4raD4h9coiyEBL4Bm0zjDwxC2CyPiTwsP3zFuhot6y9Beg@mail.gmail.com Fixes: 2a69c450083d ("ext4: using nofail preallocation in ext4_es_insert_extent()") Cc: stable@kernel.org Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230815070808.3377171-1-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: remove redundant checks of s_encodingEric Biggers2023-08-272-4/+4
| | | | | | | | | | | | | | | | | | | | Now that ext4 does not allow inodes with the casefold flag to be instantiated when unsupported, it's unnecessary to repeatedly check for support later on during random filesystem operations. Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20230814182903.37267-3-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: reject casefold inode flag without casefold featureEric Biggers2023-08-271-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is invalid for the casefold inode flag to be set without the casefold superblock feature flag also being set. e2fsck already considers this case to be invalid and handles it by offering to clear the casefold flag on the inode. __ext4_iget() also already considered this to be invalid, sort of, but it only got so far as logging an error message; it didn't actually reject the inode. Make it reject the inode so that other code doesn't have to handle this case. This matches what f2fs does. Note: we could check 's_encoding != NULL' instead of ext4_has_feature_casefold(). This would make the check robust against the casefold feature being enabled by userspace writing to the page cache of the mounted block device. However, it's unsolvable in general for filesystems to be robust against concurrent writes to the page cache of the mounted block device. Though this very particular scenario involving the casefold feature is solvable, we should not pretend that we can support this model, so let's just check the casefold feature. tune2fs already forbids enabling casefold on a mounted filesystem. Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20230814182903.37267-2-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: use LIST_HEAD() to initialize the list_head in mballoc.cRuan Jinjie2023-08-271-13/+5
| | | | | | | | | | | | | | | | Use LIST_HEAD() to initialize the list_head instead of open-coding it. Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com> Link: https://lore.kernel.org/r/20230812071839.3481909-1-ruanjinjie@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: do not mark inode dirty every time when appending using delallocLiu Song2023-08-271-26/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the delalloc append write scenario, if inode's i_size is extended due to buffer write, there are delalloc writes pending in the range up to i_size, and no need to touch i_disksize since writeback will push i_disksize up to i_size eventually. Offers significant performance improvement in high-frequency append write scenarios. I conducted tests in my 32-core environment by launching 32 concurrent threads to append write to the same file. Each write operation had a length of 1024 bytes and was repeated 100000 times. Without using this patch, the test was completed in 7705 ms. However, with this patch, the test was completed in 5066 ms, resulting in a performance improvement of 34%. Moreover, in test scenarios of Kafka version 2.6.2, using packet size of 2K, with this patch resulted in a 10% performance improvement. Signed-off-by: Liu Song <liusong@linux.alibaba.com> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230810154333.84921-1-liusong@linux.alibaba.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: rename s_error_work to s_sb_upd_workTheodore Ts'o2023-08-272-19/+22
| | | | | | | | | | | | | | | | | | | | The most common use that s_error_work will get scheduled is now the periodic update of the superblock. So rename it to s_sb_upd_work. Also rename the function flush_stashed_error_work() to update_super_work(). Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: add periodic superblock update checkVitaliy Kuznetsov2023-08-271-1/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a mechanism to periodically check and update the superblock within the ext4 file system. The main purpose of this patch is to keep the disk superblock up to date. The update will be performed if more than one hour has passed since the last update, and if more than 16MB of data have been written to disk. This check and update is performed within the ext4_journal_commit_callback function, ensuring that the superblock is written while the disk is active, rather than based on a timer that may trigger during disk idle periods. Discussion https://www.spinics.net/lists/linux-ext4/msg85865.html Signed-off-by: Vitaliy Kuznetsov <vk.en.mail@gmail.com> Link: https://lore.kernel.org/r/20230810143852.40228-1-vk.en.mail@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: drop dio overwrite only flag and associated warningBrian Foster2023-08-271-15/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit referenced below opened up concurrent unaligned dio under shared locking for pure overwrites. In doing so, it enabled use of the IOMAP_DIO_OVERWRITE_ONLY flag and added a warning on unexpected -EAGAIN returns as an extra precaution, since ext4 does not retry writes in such cases. The flag itself is advisory in this case since ext4 checks for unaligned I/Os and uses appropriate locking up front, rather than on a retry in response to -EAGAIN. As it turns out, the warning check is susceptible to false positives because there are scenarios where -EAGAIN can be expected from lower layers without necessarily having IOCB_NOWAIT set on the iocb. For example, one instance of the warning has been seen where io_uring sets IOCB_HIPRI, which in turn results in REQ_POLLED|REQ_NOWAIT on the bio. This results in -EAGAIN if the block layer is unable to allocate a request, etc. [Note that there is an outstanding patch to untangle REQ_POLLED and REQ_NOWAIT such that the latter relies on IOCB_NOWAIT, which would also address this instance of the warning.] Another instance of the warning has been reproduced by syzbot. A dio write is interrupted down in __get_user_pages_locked() waiting on the mm lock and returns -EAGAIN up the stack. If the iomap dio iteration layer has made no progress on the write to this point, -EAGAIN returns up to the filesystem and triggers the warning. This use of the overwrite flag in ext4 is precautionary and half-baked. I.e., ext4 doesn't actually implement overwrite checking in the iomap callbacks when the flag is set, so the only extra verification it provides are i_size checks in the generic iomap dio layer. Combined with the tendency for false positives, the added verification is not worth the extra trouble. Remove the flag, associated warning, and update the comments to document when concurrent unaligned dio writes are allowed and why said flag is not used. Cc: stable@kernel.org Reported-by: syzbot+5050ad0fb47527b1808a@syzkaller.appspotmail.com Reported-by: Pengfei Xu <pengfei.xu@intel.com> Fixes: 310ee0902b8d ("ext4: allow concurrent unaligned dio overwrites") Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230810165559.946222-1-bfoster@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: add correct group descriptors and reserved GDT blocks to system zoneWang Jianjian2023-08-273-8/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When setup_system_zone, flex_bg is not initialized so it is always 1. Use a new helper function, ext4_num_base_meta_blocks() which does not depend on sbi->s_log_groups_per_flex being initialized. [ Squashed two patches in the Link URL's below together into a single commit, which is simpler to review/understand. Also fix checkpatch warnings. --TYT ] Cc: stable@kernel.org Signed-off-by: Wang Jianjian <wangjianjian0@foxmail.com> Link: https://lore.kernel.org/r/tencent_21AF0D446A9916ED5C51492CC6C9A0A77B05@qq.com Link: https://lore.kernel.org/r/tencent_D744D1450CC169AEA77FCF0A64719909ED05@qq.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: remove unused function declarationCai Xinchen2023-08-271-6/+0
| | | | | | | | | | | | | | | | | | These functions do not have its function implementation. So those function declaration is useless. Remove these Signed-off-by: Cai Xinchen <caixinchen1@huawei.com> Link: https://lore.kernel.org/r/20230802030025.173148-1-caixinchen1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: mballoc: avoid garbage value from errSu Hui2023-08-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clang's static analysis warning: fs/ext4/mballoc.c line 4178, column 6, Branch condition evaluates to a garbage value. err is uninitialized and will be judged when 'len <= 0' or it first enters the loop while the condition "!ext4_sb_block_valid()" is true. Although this can't make problems now, it's better to correct it. Signed-off-by: Su Hui <suhui@nfschina.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20230725043310.1227621-1-suhui@nfschina.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: use sbi instead of EXT4_SB(sb) in ext4_mb_new_blocks_simple()Lu Hongfei2023-08-271-1/+1
| | | | | | | | | | | | Signed-off-by: Lu Hongfei <luhongfei@vivo.com> Link: https://lore.kernel.org/r/20230707115907.26637-1-luhongfei@vivo.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: change the type of blocksize in ext4_mb_init_cache()Lu Hongfei2023-08-271-1/+1
| | | | | | | | | | | | | | | | | | | | The return value type of i_blocksize() is 'unsigned int', so the type of blocksize has been modified from 'int' to 'unsigned int' to ensure data type consistency. Signed-off-by: Lu Hongfei <luhongfei@vivo.com> Link: https://lore.kernel.org/r/20230707105516.9156-1-luhongfei@vivo.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: fix unttached inode after power cut with orphan file feature enabledZhihao Cheng2023-08-271-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Running generic/475(filesystem consistent tests after power cut) could easily trigger unattached inode error while doing fsck: Unattached zero-length inode 39405. Clear? no Unattached inode 39405 Connect to /lost+found? no Above inconsistence is caused by following process: P1 P2 ext4_create inode = ext4_new_inode_start_handle // itable records nlink=1 ext4_add_nondir err = ext4_add_entry // ENOSPC ext4_append ext4_bread ext4_getblk ext4_map_blocks // returns ENOSPC drop_nlink(inode) // won't be updated into disk inode ext4_orphan_add(handle, inode) ext4_orphan_file_add ext4_journal_stop(handle) jbd2_journal_commit_transaction // commit success >> power cut << ext4_fill_super ext4_load_and_init_journal // itable records nlink=1 ext4_orphan_cleanup ext4_process_orphan if (inode->i_nlink) // true, inode won't be deleted Then, allocated inode will be reserved on disk and corresponds to no dentries, so e2fsck reports 'unattached inode' problem. The problem won't happen if orphan file feature is disabled, because ext4_orphan_add() will update disk inode in orphan list mode. There are several places not updating disk inode while putting inode into orphan area, such as ext4_add_nondir(), ext4_symlink() and whiteout in ext4_rename(). Fix it by updating inode into disk in all error branches of these places. Link: https://bugzilla.kernel.org/show_bug.cgi?id=217605 Fixes: 02f310fcf47f ("ext4: Speedup ext4 orphan inode handling") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230628132011.650383-1-chengzhihao1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: ext4_get_{dev}_journal return proper error valueZhang Yi2023-08-271-22/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ext4_get_journal() and ext4_get_dev_journal() return NULL if they failed to init journal, making them return proper error value instead, also rename them to ext4_open_{inode,dev}_journal(). [ Folded fix to ext4_calculate_overhead() to check for an ERR_PTR instead of NULL. ] Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230811063610.2980059-13-yi.zhang@huaweicloud.com Reported-by: syzbot+b3123e6d9842e526de39@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20230826011029.2023140-1-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: cleanup ext4_get_dev_journal() and ext4_get_journal()Zhang Yi2023-08-231-60/+49
| | | | | | | | | | | | | | | | | | | | | | | | Factor out a new helper form ext4_get_dev_journal() to get external journal bdev and check validation of this device, drop ext4_blkdev_get() helper, and also remove duplicate check of journal feature. It makes ext4_get_dev_journal() more clear than before. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230811063610.2980059-12-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * jbd2: jbd2_journal_init_{dev,inode} return proper error return valueZhang Yi2023-08-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Current jbd2_journal_init_{dev,inode} return NULL if some error happens, make them to pass out proper error return value. [ Fix from Yang Yingliang folded in. ] Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230811063610.2980059-11-yi.zhang@huaweicloud.com Link: https://lore.kernel.org/r/20230822030018.644419-1-yangyingliang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: don't use CR_BEST_AVAIL_LEN for non-regular filesRitesh Harjani2023-08-051-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using CR_BEST_AVAIL_LEN only make sense for regular files, as for non-regular files we never normalize the allocation request length i.e. goal len is same as original length (ac_g_ex.fe_len == ac_o_ex.fe_len). Hence there is no scope of trimming the goal length to make it satisfy original request len. Thus this patch avoids using CR_BEST_AVAIL_LEN criteria for non-regular files request. Cc: stable@kernel.org Fixes: 33122aa930f1 ("ext4: Add allocation criteria 1.5 (CR1_5)") Reported-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Tested-by: Eric Whitney <enwlinux@gmail.com> Link: https://lore.kernel.org/r/2a694c748ff8b8c4b416995a24f06f07b55047a8.1689516047.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: fix memory leaks in ext4_fname_{setup_filename,prepare_lookup}Luís Henriques2023-08-051-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the filename casefolding fails, we'll be leaking memory from the fscrypt_name struct, namely from the 'crypto_buf.name' member. Make sure we free it in the error path on both ext4_fname_setup_filename() and ext4_fname_prepare_lookup() functions. Cc: stable@kernel.org Fixes: 1ae98e295fa2 ("ext4: optimize match for casefolded encrypted dirs") Signed-off-by: Luís Henriques <lhenriques@suse.de> Reviewed-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20230803091713.13239-1-lhenriques@suse.de Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: correct some stale comment of criteriaKemeng Shi2023-08-031-4/+4
| | | | | | | | | | | | | | | | | | | | We named criteria with CR_XXX, correct stale comment to criteria with raw number. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-11-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: return found group directly in ext4_mb_choose_next_group_best_availKemeng Shi2023-08-031-10/+8
| | | | | | | | | | | | | | | | | | | | Return good group when it's found in loop to remove futher check if good group is found after loop. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-10-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: return found group directly in ext4_mb_choose_next_group_goal_fastKemeng Shi2023-08-031-8/+6
| | | | | | | | | | | | | | | | | | | | Return good group when it's found in loop to remove futher check if good group is found after loop. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-9-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: remove unused ext4_{set}/{clear}_bit_atomicKemeng Shi2023-08-031-2/+0
| | | | | | | | | | | | | | | | | | | | Remove ext4_set_bit_atomic and ext4_clear_bit_atomic which are defined but not used. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-8-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: replace the traditional ternary conditional operator with with max()/min()Kemeng Shi2023-08-031-4/+2
| | | | | | | | | | | | | | | | | | Replace the traditional ternary conditional operator with with max()/min() Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-7-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: remove unnecessary return for void functionKemeng Shi2023-08-031-9/+1
| | | | | | | | | | | | | | | | | | The return at end of void function is unnecessary, just remove it. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-6-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: use is_power_of_2 helper in ext4_mb_regular_allocatorKemeng Shi2023-08-031-4/+1
| | | | | | | | | | | | | | | | | | Use intuitive is_power_of_2 helper in ext4_mb_regular_allocator. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-5-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: return found group directly in ext4_mb_choose_next_group_p2_alignedKemeng Shi2023-08-031-14/+7
| | | | | | | | | | | | | | | | | | | | Return good group when it's found in loop to remove unnecessary NULL initialization of grp and futher check if good group is found after loop. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-4-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: avoid potential data overflow in next_linear_groupKemeng Shi2023-08-031-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | ngroups is ext4_group_t (unsigned int) while next_linear_group treat it in int. If ngroups is bigger than max number described by int, it will be treat as a negative number. Then "return group + 1 >= ngroups ? 0 : group + 1;" may keep returning 0. Switch int to ext4_group_t in next_linear_group to fix the overflow. Fixes: 196e402adf2e ("ext4: improve cr 0 / cr 1 group scanning") Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-3-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: correct grp validation in ext4_mb_good_groupKemeng Shi2023-08-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | Group corruption check will access memory of grp and will trigger kernel crash if grp is NULL. So do NULL check before corruption check. Fixes: 5354b2af3406 ("ext4: allow ext4_get_group_info() to fail") Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230801143204.2284343-2-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: replace CR_FAST macro with inline function for readabilityOjaswin Mujoo2023-08-032-7/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace CR_FAST with ext4_mb_cr_expensive() inline function for better readability. This function returns true if the criteria is one of the expensive/slower ones where lots of disk IO/prefetching is acceptable. No functional changes are intended in this patch. Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20230630085927.140137-1-ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: replace read-only check for shutdown check in mmp codeJan Kara2023-07-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | The multi-mount protection kthread checks for read-only filesystem and aborts in that case. The remount code actually handles stopping of the kthread on remount so the only purpose of the check is in case of emergency remount read-only. Replace the check for read-only filesystem with a check for shutdown filesystem as running MMP on such is risky anyway and it makes ordering of things during remount simpler. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230616165109.21695-11-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: drop read-only check from ext4_force_commit()Jan Kara2023-07-291-7/+1
| | | | | | | | | | | | | | | | | | | | JBD2 code will quickly return without doing anything when there's nothing to commit so there's no point in the read-only check in ext4_force_commit(). Just drop it. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230616165109.21695-10-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: drop read-only check in ext4_write_inode()Jan Kara2023-07-291-2/+1
| | | | | | | | | | | | | | | | | | | | | | We should not have dirty inodes on read-only filesystem. Also silently bailing without writing anything would be a problem when we enable quotas during remount while the filesystem is read-only. So drop the read-only check. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230616165109.21695-9-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: drop read-only check in ext4_init_inode_table()Jan Kara2023-07-291-6/+0
| | | | | | | | | | | | | | | | | | | | We better should not be initializing inode tables on read-only filesystem. The following transaction start will warn us and make the function bail anyway so drop the pointless check. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230616165109.21695-8-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>