kernel.git/fs/ext4/ext4.h, branch linux-5.12.y

ext4: fix memory leak in ext4_fill_super

2021-07-19T08:01:28Z

commit 618f003199c6188e01472b03cdbba227f1dc5f24 upstream. static int kthread(void *_create) will return -ENOMEM or -EINTR in case of internal failure or kthread_stop() call happens before threadfn call. To prevent fancy error checking and make code more straightforward we moved all cleanup code out of kmmpd threadfn. Also, dropped struct mmpd_data at all. Now struct super_block is a threadfn data and struct buffer_head embedded into struct ext4_sb_info. Reported-by: syzbot+d9e482e303930fa4f6ff@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Link: https://lore.kernel.org/r/20210430185046.15742-1-paskripkin@gmail.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix rename whiteout with fast commit

2021-03-21T04:38:18Z

This patch adds rename whiteout support in fast commits. Note that the whiteout object that gets created is actually char device. Which imples, the function ext4_inode_journal_mode(struct inode *inode) would return "JOURNAL_DATA" for this inode. This has a consequence in fast commit code that it will make creation of the whiteout object a fast-commit ineligible behavior and thus will fall back to full commits. With this patch, this can be observed by running fast commits with rename whiteout and seeing the stats generated by ext4_fc_stats tracepoint as follows: ext4_fc_stats: dev 254:32 fc ineligible reasons: XATTR:0, CROSS_RENAME:0, JOURNAL_FLAG_CHANGE:0, NO_MEM:0, SWAP_BOOT:0, RESIZE:0, RENAME_DIR:0, FALLOC_RANGE:0, INODE_JOURNAL_DATA:16; num_commits:6, ineligible: 6, numblks: 3 So in short, this patch guarantees that in case of rename whiteout, we fall back to full commits. Amir mentioned that instead of creating a new whiteout object for every rename, we can create a static whiteout object with irrelevant nlink. That will make fast commits to not fall back to full commit. But until this happens, this patch will ensure correctness by falling back to full commits. Fixes: 8016e29f4362 ("ext4: fast commit recovery path") Cc: stable@kernel.org Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20210316221921.1124955-1-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o

ext4: shrink race window in ext4_should_retry_alloc()

2021-03-06T16:56:10Z

When generic/371 is run on kvm-xfstests using 5.10 and 5.11 kernels, it fails at significant rates on the two test scenarios that disable delayed allocation (ext3conv and data_journal) and force actual block allocation for the fallocate and pwrite functions in the test. The failure rate on 5.10 for both ext3conv and data_journal on one test system typically runs about 85%. On 5.11, the failure rate on ext3conv sometimes drops to as low as 1% while the rate on data_journal increases to nearly 100%. The observed failures are largely due to ext4_should_retry_alloc() cutting off block allocation retries when s_mb_free_pending (used to indicate that a transaction in progress will free blocks) is 0. However, free space is usually available when this occurs during runs of generic/371. It appears that a thread attempting to allocate blocks is just missing transaction commits in other threads that increase the free cluster count and reset s_mb_free_pending while the allocating thread isn't running. Explicitly testing for free space availability avoids this race. The current code uses a post-increment operator in the conditional expression that determines whether the retry limit has been exceeded. This means that the conditional expression uses the value of the retry counter before it's increased, resulting in an extra retry cycle. The current code actually retries twice before hitting its retry limit rather than once. Increasing the retry limit to 3 from the current actual maximum retry count of 2 in combination with the change described above reduces the observed failure rate to less that 0.1% on both ext3conv and data_journal with what should be limited impact on users sensitive to the overhead caused by retries. A per filesystem percpu counter exported via sysfs is added to allow users or developers to track the number of times the retry limit is exceeded without resorting to debugging methods. This should provide some insight into worst case retry behavior. Signed-off-by: Eric Whitney Link: https://lore.kernel.org/r/20210218151132.19678-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o

ext4: support idmapped mounts

2021-01-24T13:43:46Z

Enable idmapped mounts for ext4. All dedicated helpers we need for this exist. So this basically just means we're passing down the user_namespace argument from the VFS methods to the relevant helpers. Let's create simple example where we idmap an ext4 filesystem: root@f2-vm:~# truncate -s 5G ext4.img root@f2-vm:~# mkfs.ext4 ./ext4.img mke2fs 1.45.5 (07-Jan-2020) Discarding device blocks: done Creating filesystem with 1310720 4k blocks and 327680 inodes Filesystem UUID: 3fd91794-c6ca-4b0f-9964-289a000919cf Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736 Allocating group tables: done Writing inode tables: done Creating journal (16384 blocks): done Writing superblocks and filesystem accounting information: done root@f2-vm:~# losetup -f --show ./ext4.img /dev/loop0 root@f2-vm:~# mount /dev/loop0 /mnt root@f2-vm:~# ls -al /mnt/ total 24 drwxr-xr-x 3 root root 4096 Oct 28 13:34 . drwxr-xr-x 30 root root 4096 Oct 28 13:22 .. drwx------ 2 root root 16384 Oct 28 13:34 lost+found # Let's create an idmapped mount at /idmapped1 where we map uid and gid # 0 to uid and gid 1000 root@f2-vm:/# ./mount-idmapped --map-mount b:0:1000:1 /mnt/ /idmapped1/ root@f2-vm:/# ls -al /idmapped1/ total 24 drwxr-xr-x 3 ubuntu ubuntu 4096 Oct 28 13:34 . drwxr-xr-x 30 root root 4096 Oct 28 13:22 .. drwx------ 2 ubuntu ubuntu 16384 Oct 28 13:34 lost+found # Let's create an idmapped mount at /idmapped2 where we map uid and gid # 0 to uid and gid 2000 root@f2-vm:/# ./mount-idmapped --map-mount b:0:2000:1 /mnt/ /idmapped2/ root@f2-vm:/# ls -al /idmapped2/ total 24 drwxr-xr-x 3 2000 2000 4096 Oct 28 13:34 . drwxr-xr-x 31 root root 4096 Oct 28 13:39 .. drwx------ 2 2000 2000 16384 Oct 28 13:34 lost+found Let's create another example where we idmap the rootfs filesystem without a mapping for uid 0 and gid 0: # Create an idmapped mount of for a full POSIX range of rootfs under # /mnt but without a mapping for uid 0 to reduce attack surface root@f2-vm:/# ./mount-idmapped --map-mount b:1:1:65536 / /mnt/ # Since we don't have a mapping for uid and gid 0 all files owned by # uid and gid 0 should show up as uid and gid 65534: root@f2-vm:/# ls -al /mnt/ total 664 drwxr-xr-x 31 nobody nogroup 4096 Oct 28 13:39 . drwxr-xr-x 31 root root 4096 Oct 28 13:39 .. lrwxrwxrwx 1 nobody nogroup 7 Aug 25 07:44 bin -> usr/bin drwxr-xr-x 4 nobody nogroup 4096 Oct 28 13:17 boot drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:48 dev drwxr-xr-x 81 nobody nogroup 4096 Oct 28 04:00 etc drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 home lrwxrwxrwx 1 nobody nogroup 7 Aug 25 07:44 lib -> usr/lib lrwxrwxrwx 1 nobody nogroup 9 Aug 25 07:44 lib32 -> usr/lib32 lrwxrwxrwx 1 nobody nogroup 9 Aug 25 07:44 lib64 -> usr/lib64 lrwxrwxrwx 1 nobody nogroup 10 Aug 25 07:44 libx32 -> usr/libx32 drwx------ 2 nobody nogroup 16384 Aug 25 07:47 lost+found drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 media drwxr-xr-x 31 nobody nogroup 4096 Oct 28 13:39 mnt drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 opt drwxr-xr-x 2 nobody nogroup 4096 Apr 15 2020 proc drwx--x--x 6 nobody nogroup 4096 Oct 28 13:34 root drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:46 run lrwxrwxrwx 1 nobody nogroup 8 Aug 25 07:44 sbin -> usr/sbin drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 srv drwxr-xr-x 2 nobody nogroup 4096 Apr 15 2020 sys drwxrwxrwt 10 nobody nogroup 4096 Oct 28 13:19 tmp drwxr-xr-x 14 nobody nogroup 4096 Oct 20 13:00 usr drwxr-xr-x 12 nobody nogroup 4096 Aug 25 07:45 var # Since we do have a mapping for uid and gid 1000 all files owned by # uid and gid 1000 should simply show up as uid and gid 1000: root@f2-vm:/# ls -al /mnt/home/ubuntu/ total 40 drwxr-xr-x 3 ubuntu ubuntu 4096 Oct 28 00:43 . drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 .. -rw------- 1 ubuntu ubuntu 2936 Oct 28 12:26 .bash_history -rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile -rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo Link: https://lore.kernel.org/r/20210121131959.646623-39-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-ext4@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner

fs: make helpers idmap mount aware

2021-01-24T13:27:20Z

Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2020-12-24T22:16:02Z

Pull ext4 updates from Ted Ts'o: "Various bug fixes and cleanups for ext4; no new features this cycle" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (29 commits) ext4: remove unnecessary wbc parameter from ext4_bio_write_page ext4: avoid s_mb_prefetch to be zero in individual scenarios ext4: defer saving error info from atomic context ext4: simplify ext4 error translation ext4: move functions in super.c ext4: make ext4_abort() use __ext4_error() ext4: standardize error message in ext4_protect_reserved_inode() ext4: remove redundant sb checksum recomputation ext4: don't remount read-only with errors=continue on reboot ext4: fix deadlock with fs freezing and EA inodes jbd2: add a helper to find out number of fast commit blocks ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h ext4: fix fall-through warnings for Clang ext4: add docs about fast commit idempotence ext4: remove the unused EXT4_CURRENT_REV macro ext4: fix an IS_ERR() vs NULL check ext4: check for invalid block size early when mounting a file system ext4: fix a memory leak of ext4_free_data ext4: delete nonsensical (commented-out) code inside ext4_xattr_block_set() ext4: update ext4_data_block_valid related comments ...

ext4: remove unnecessary wbc parameter from ext4_bio_write_page

2020-12-22T18:08:45Z

ext4_bio_write_page does not need wbc parameter, since its parameter io contains the io_wbc field. The io::io_wbc is initialized by ext4_io_submit_init which is called in ext4_writepages and ext4_writepage functions prior to ext4_bio_write_page. Therefor, when ext4_bio_write_page is called, wbc info has already been included in io parameter. Signed-off-by: Lei Chen Link: https://lore.kernel.org/r/1607669664-25656-1-git-send-email-lennychen@tencent.com Signed-off-by: Theodore Ts'o

ext4: defer saving error info from atomic context

2020-12-22T18:07:49Z

When filesystem inconsistency is detected with group locked, we currently try to modify superblock to store error there without blocking. However this can cause superblock checksum failures (or DIF/DIX failure) when the superblock is just being written out. Make error handling code just store error information in ext4_sb_info structure and copy it to on-disk superblock only in ext4_commit_super(). In case of error happening with group locked, we just postpone the superblock flushing to a workqueue. [ Added fixup so that s_first_error_* does not get updated after the file system is remounted. Also added fix for syzbot failure. - Ted ] Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20201127113405.26867-8-jack@suse.cz Signed-off-by: Theodore Ts'o Cc: Hillf Danton Reported-by: syzbot+9043030c040ce1849a60@syzkaller.appspotmail.com

Merge tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2020-12-17T19:18:00Z

Pull f2fs updates from Jaegeuk Kim: "In this round, we've made more work into per-file compression support. For example, F2FS_IOC_GET | SET_COMPRESS_OPTION provides a way to change the algorithm or cluster size per file. F2FS_IOC_COMPRESS | DECOMPRESS_FILE provides a way to compress and decompress the existing normal files manually. There is also a new mount option, compress_mode=fs|user, which can control who compresses the data. Chao also added a checksum feature with a mount option so that we are able to detect any corrupted cluster. In addition, Daniel contributed casefolding with encryption patch, which will be used for Android devices. Summary: Enhancements: - add ioctls and mount option to manage per-file compression feature - support casefolding with encryption - support checksum for compressed cluster - avoid IO starvation by replacing mutex with rwsem - add sysfs, max_io_bytes, to control max bio size Bug fixes: - fix use-after-free issue when compression and fsverity are enabled - fix consistency corruption during fault injection test - fix data offset for lseek - get rid of buffer_head which has 32bits limit in fiemap - fix some bugs in multi-partitions support - fix nat entry count calculation in shrinker - fix some stat information And, we've refactored some logics and fix minor bugs as well" * tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (36 commits) f2fs: compress: fix compression chksum f2fs: fix shift-out-of-bounds in sanity_check_raw_super() f2fs: fix race of pending_pages in decompression f2fs: fix to account inline xattr correctly during recovery f2fs: inline: fix wrong inline inode stat f2fs: inline: correct comment in f2fs_recover_inline_data f2fs: don't check PAGE_SIZE again in sanity_check_raw_super() f2fs: convert to F2FS_*_INO macro f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size f2fs: don't allow any writes on readonly mount f2fs: avoid race condition for shrinker count f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE f2fs: add compress_mode mount option f2fs: Remove unnecessary unlikely() f2fs: init dirty_secmap incorrectly f2fs: remove buffer_head which has 32bits limit f2fs: fix wrong block count instead of bytes f2fs: use new conversion functions between blks and bytes f2fs: rename logical_to_blk and blk_to_logical f2fs: fix kbytes written stat for multi-device case ...

ext4: make ext4_abort() use __ext4_error()

2020-12-17T18:30:55Z

The only difference between __ext4_abort() and __ext4_error() is that the former one ignores errors=continue mount option. Unify the code to reduce duplication. Signed-off-by: Jan Kara Reviewed-by: Andreas Dilger Link: https://lore.kernel.org/r/20201127113405.26867-5-jack@suse.cz Signed-off-by: Theodore Ts'o