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2021-07-08ext4: inline jbd2_journal_[un]register_shrinker()Theodore Ts'o1-8/+0
The function jbd2_journal_unregister_shrinker() was getting called twice when the file system was getting unmounted. On Power and ARM platforms this was causing kernel crash when unmounting the file system, when a percpu_counter was destroyed twice. Fix this by removing jbd2_journal_[un]register_shrinker() functions, and inlining the shrinker setup and teardown into journal_init_common() and jbd2_journal_destroy(). This means that ext4 and ocfs2 now no longer need to know about registering and unregistering jbd2's shrinker. Also, while we're at it, rename the percpu counter from j_jh_shrink_count to j_checkpoint_jh_count, since this makes it clearer what this counter is intended to track. Link: https://lore.kernel.org/r/20210705145025.3363130-1-tytso@mit.edu Fixes: 4ba3fcdde7e3 ("jbd2,ext4: add a shrinker to release checkpointed buffers") Reported-by: Jon Hunter <jonathanh@nvidia.com> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-07-08ext4: fix possible UAF when remounting r/o a mmp-protected file systemTheodore Ts'o1-1/+5
After commit 618f003199c6 ("ext4: fix memory leak in ext4_fill_super"), after the file system is remounted read-only, there is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to point at freed memory, which the call to ext4_stop_mmpd() can trip over. Fix this by only allowing kmmpd() to exit when it is stopped via ext4_stop_mmpd(). Link: https://lore.kernel.org/r/20210707002433.3719773-1-tytso@mit.edu Reported-by: Ye Bin <yebin10@huawei.com> Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2021-07-01ext4: fix WARN_ON_ONCE(!buffer_uptodate) after an error writing the superblockYe Bin1-2/+10
If a writeback of the superblock fails with an I/O error, the buffer is marked not uptodate. However, this can cause a WARN_ON to trigger when we attempt to write superblock a second time. (Which might succeed this time, for cerrtain types of block devices such as iSCSI devices over a flaky network.) Try to detect this case in flush_stashed_error_work(), and also change __ext4_handle_dirty_metadata() so we always set the uptodate flag, not just in the nojournal case. Before this commit, this problem can be repliciated via: 1. dmsetup create dust1 --table '0 2097152 dust /dev/sdc 0 4096' 2. mount /dev/mapper/dust1 /home/test 3. dmsetup message dust1 0 addbadblock 0 10 4. cd /home/test 5. echo "XXXXXXX" > t After a few seconds, we got following warning: [ 80.654487] end_buffer_async_write: bh=0xffff88842f18bdd0 [ 80.656134] Buffer I/O error on dev dm-0, logical block 0, lost async page write [ 85.774450] EXT4-fs error (device dm-0): ext4_check_bdev_write_error:193: comm kworker/u16:8: Error while async write back metadata [ 91.415513] mark_buffer_dirty: bh=0xffff88842f18bdd0 [ 91.417038] ------------[ cut here ]------------ [ 91.418450] WARNING: CPU: 1 PID: 1944 at fs/buffer.c:1092 mark_buffer_dirty.cold+0x1c/0x5e [ 91.440322] Call Trace: [ 91.440652] __jbd2_journal_temp_unlink_buffer+0x135/0x220 [ 91.441354] __jbd2_journal_unfile_buffer+0x24/0x90 [ 91.441981] __jbd2_journal_refile_buffer+0x134/0x1d0 [ 91.442628] jbd2_journal_commit_transaction+0x249a/0x3240 [ 91.443336] ? put_prev_entity+0x2a/0x200 [ 91.443856] ? kjournald2+0x12e/0x510 [ 91.444324] kjournald2+0x12e/0x510 [ 91.444773] ? woken_wake_function+0x30/0x30 [ 91.445326] kthread+0x150/0x1b0 [ 91.445739] ? commit_timeout+0x20/0x20 [ 91.446258] ? kthread_flush_worker+0xb0/0xb0 [ 91.446818] ret_from_fork+0x1f/0x30 [ 91.447293] ---[ end trace 66f0b6bf3d1abade ]--- Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20210615090537.3423231-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-29ext4: notify sysfs on errors_count value changeJonathan Davies1-0/+2
After s_error_count is incremented, signal the change in the corresponding sysfs attribute via sysfs_notify. This allows userspace to poll() on changes to /sys/fs/ext4/*/errors_count. [ Moved call of ext4_notify_error_sysfs() to flush_stashed_error_work() to avoid BUG's caused by calling sysfs_notify trying to sleep after being called from an invalid context. -- TYT ] Signed-off-by: Jonathan Davies <jonathan.davies@nutanix.com> Link: https://lore.kernel.org/r/20210611140209.28903-1-jonathan.davies@nutanix.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-24ext4: remove bdev_try_to_free_page() callbackZhang Yi1-21/+0
After we introduce a jbd2 shrinker to release checkpointed buffer's journal head, we could free buffer without bdev_try_to_free_page() under memory pressure. So this patch remove the whole bdev_try_to_free_page() callback directly. It also remove many use-after-free issues relate to it together. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210610112440.3438139-8-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-24jbd2,ext4: add a shrinker to release checkpointed buffersZhang Yi1-0/+8
Current metadata buffer release logic in bdev_try_to_free_page() have a lot of use-after-free issues when umount filesystem concurrently, and it is difficult to fix directly because ext4 is the only user of s_op->bdev_try_to_free_page callback and we may have to add more special refcount or lock that is only used by ext4 into the common vfs layer, which is unacceptable. One better solution is remove the bdev_try_to_free_page callback, but the real problem is we cannot easily release journal_head on the checkpointed buffer, so try_to_free_buffers() cannot release buffers and page under memory pressure, which is more likely to trigger out-of-memory. So we cannot remove the callback directly before we find another way to release journal_head. This patch introduce a shrinker to free journal_head on the checkpointed transaction. After the journal_head got freed, try_to_free_buffers() could free buffer properly. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210610112440.3438139-6-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-22ext4: add discard/zeroout flags to journal flushLeah Rumancik1-3/+3
Add a flags argument to jbd2_journal_flush to enable discarding or zero-filling the journal blocks while flushing the journal. Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com> Link: https://lore.kernel.org/r/20210518151327.130198-1-leah.rumancik@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-17ext4: return error code when ext4_fill_flex_info() failsYang Yingliang1-0/+1
After commit c89128a00838 ("ext4: handle errors on ext4_commit_super"), 'ret' may be set to 0 before calling ext4_fill_flex_info(), if ext4_fill_flex_info() fails ext4_mount() doesn't return error code, it makes 'root' is null which causes crash in legacy_get_tree(). Fixes: c89128a00838 ("ext4: handle errors on ext4_commit_super") Reported-by: Hulk Robot <hulkci@huawei.com> Cc: <stable@vger.kernel.org> # v4.18+ Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20210510111051.55650-1-yangyingliang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-17ext4: cleanup in-core orphan list if ext4_truncate() failed to get a ↵Zhang Yi1-1/+8
transaction handle In ext4_orphan_cleanup(), if ext4_truncate() failed to get a transaction handle, it didn't remove the inode from the in-core orphan list, which may probably trigger below error dump in ext4_destroy_inode() during the final iput() and could lead to memory corruption on the later orphan list changes. EXT4-fs (sda): Inode 6291467 (00000000b8247c67): orphan list check failed! 00000000b8247c67: 0001f30a 00000004 00000000 00000023 ............#... 00000000e24cde71: 00000006 014082a3 00000000 00000000 ......@......... 0000000072c6a5ee: 00000000 00000000 00000000 00000000 ................ ... This patch fix this by cleanup in-core orphan list manually if ext4_truncate() return error. Cc: stable@kernel.org Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210507071904.160808-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-17ext4: fix memory leak in ext4_fill_superPavel Skripkin1-6/+4
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 <paskripkin@gmail.com> Link: https://lore.kernel.org/r/20210430185046.15742-1-paskripkin@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-06-06Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds1-2/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Miscellaneous ext4 bug fixes" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: Only advertise encrypted_casefold when encryption and unicode are enabled ext4: fix no-key deletion for encrypt+casefold ext4: fix memory leak in ext4_fill_super ext4: fix fast commit alignment issues ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed ext4: fix accessing uninit percpu counter variable with fast_commit ext4: fix memory leak in ext4_mb_init_backend on error path.
2021-06-06ext4: fix memory leak in ext4_fill_superAlexey Makhalov1-2/+9
Buffer head references must be released before calling kill_bdev(); otherwise the buffer head (and its page referenced by b_data) will not be freed by kill_bdev, and subsequently that bh will be leaked. If blocksizes differ, sb_set_blocksize() will kill current buffers and page cache by using kill_bdev(). And then super block will be reread again but using correct blocksize this time. sb_set_blocksize() didn't fully free superblock page and buffer head, and being busy, they were not freed and instead leaked. This can easily be reproduced by calling an infinite loop of: systemctl start <ext4_on_lvm>.mount, and systemctl stop <ext4_on_lvm>.mount ... since systemd creates a cgroup for each slice which it mounts, and the bh leak get amplified by a dying memory cgroup that also never gets freed, and memory consumption is much more easily noticed. Fixes: ce40733ce93d ("ext4: Check for return value from sb_set_blocksize") Fixes: ac27a0ec112a ("ext4: initial copy of files from ext3") Link: https://lore.kernel.org/r/20210521075533.95732-1-amakhalov@vmware.com Signed-off-by: Alexey Makhalov <amakhalov@vmware.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2021-04-30Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-43/+73
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "New features for ext4 this cycle include support for encrypted casefold, ensure that deleted file names are cleared in directory blocks by zeroing directory entries when they are unlinked or moved as part of a hash tree node split. We also improve the block allocator's performance on a freshly mounted file system by prefetching block bitmaps. There are also the usual cleanups and bug fixes, including fixing a page cache invalidation race when there is mixed buffered and direct I/O and the block size is less than page size, and allow the dax flag to be set and cleared on inline directories" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits) ext4: wipe ext4_dir_entry2 upon file deletion ext4: Fix occasional generic/418 failure fs: fix reporting supported extra file attributes for statx() ext4: allow the dax flag to be set and cleared on inline directories ext4: fix debug format string warning ext4: fix trailing whitespace ext4: fix various seppling typos ext4: fix error return code in ext4_fc_perform_commit() ext4: annotate data race in jbd2_journal_dirty_metadata() ext4: annotate data race in start_this_handle() ext4: fix ext4_error_err save negative errno into superblock ext4: fix error code in ext4_commit_super ext4: always panic when errors=panic is specified ext4: delete redundant uptodate check for buffer ext4: do not set SB_ACTIVE in ext4_orphan_cleanup() ext4: make prefetch_block_bitmaps default ext4: add proc files to monitor new structures ext4: improve cr 0 / cr 1 group scanning ext4: add MB_NUM_ORDERS macro ext4: add mballoc stats proc file ...
2021-04-29Merge tag 'fsnotify_for_v5.13-rc1' of ↵Linus Torvalds1-4/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: - support for limited fanotify functionality for unpriviledged users - faster merging of fanotify events - a few smaller fsnotify improvements * tag 'fsnotify_for_v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: shmem: allow reporting fanotify events with file handles on tmpfs fs: introduce a wrapper uuid_to_fsid() fanotify_user: use upper_32_bits() to verify mask fanotify: support limited functionality for unprivileged users fanotify: configurable limits via sysfs fanotify: limit number of event merge attempts fsnotify: use hash table for faster events merge fanotify: mix event info and pid into merge key hash fanotify: reduce event objectid to 29-bit hash fsnotify: allow fsnotify_{peek,remove}_first_event with empty queue
2021-04-19fs: introduce a wrapper uuid_to_fsid()Amir Goldstein1-4/+1
Some filesystem's use a digest of their uuid for f_fsid. Create a simple wrapper for this open coded folding. Filesystems that have a non null uuid but use the block device number for f_fsid may also consider using this helper. [JK: Added missing asm/byteorder.h include] Link: https://lore.kernel.org/r/20210322173944.449469-2-amir73il@gmail.com Acked-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2021-04-09ext4: fix trailing whitespaceJack Qiu1-1/+1
Made suggested modifications from checkpatch in reference to ERROR: trailing whitespace Signed-off-by: Jack Qiu <jack.qiu@huawei.com> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20210409042035.15516-1-jack.qiu@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-09ext4: fix error code in ext4_commit_superFengnan Chang1-2/+4
We should set the error code when ext4_commit_super check argument failed. Found in code review. Fixes: c4be0c1dc4cdc ("filesystem freeze: add error handling of write_super_lockfs/unlockfs"). Cc: stable@kernel.org Signed-off-by: Fengnan Chang <changfengnan@vivo.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20210402101631.561-1-changfengnan@vivo.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-09ext4: always panic when errors=panic is specifiedYe Bin1-3/+4
Before commit 014c9caa29d3 ("ext4: make ext4_abort() use __ext4_error()"), the following series of commands would trigger a panic: 1. mount /dev/sda -o ro,errors=panic test 2. mount /dev/sda -o remount,abort test After commit 014c9caa29d3, remounting a file system using the test mount option "abort" will no longer trigger a panic. This commit will restore the behaviour immediately before commit 014c9caa29d3. (However, note that the Linux kernel's behavior has not been consistent; some previous kernel versions, including 5.4 and 4.19 similarly did not panic after using the mount option "abort".) This also makes a change to long-standing behaviour; namely, the following series commands will now cause a panic, when previously it did not: 1. mount /dev/sda -o ro,errors=panic test 2. echo test > /sys/fs/ext4/sda/trigger_fs_error However, this makes ext4's behaviour much more consistent, so this is a good thing. Cc: stable@kernel.org Fixes: 014c9caa29d3 ("ext4: make ext4_abort() use __ext4_error()") Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20210401081903.3421208-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-09ext4: do not set SB_ACTIVE in ext4_orphan_cleanup()Zhang Yi1-3/+0
When CONFIG_QUOTA is enabled, if we failed to mount the filesystem due to some error happens behind ext4_orphan_cleanup(), it will end up triggering a after free issue of super_block. The problem is that ext4_orphan_cleanup() will set SB_ACTIVE flag if CONFIG_QUOTA is enabled, after we cleanup the truncated inodes, the last iput() will put them into the lru list, and these inodes' pages may probably dirty and will be write back by the writeback thread, so it could be raced by freeing super_block in the error path of mount_bdev(). After check the setting of SB_ACTIVE flag in ext4_orphan_cleanup(), it was used to ensure updating the quota file properly, but evict inode and trash data immediately in the last iput does not affect the quotafile, so setting the SB_ACTIVE flag seems not required[1]. Fix this issue by just remove the SB_ACTIVE setting. [1] https://lore.kernel.org/linux-ext4/99cce8ca-e4a0-7301-840f-2ace67c551f3@huawei.com/T/#m04990cfbc4f44592421736b504afcc346b2a7c00 Cc: stable@kernel.org Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Tested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210331033138.918975-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-09ext4: make prefetch_block_bitmaps defaultHarshad Shirwadkar1-7/+8
Block bitmap prefetching is needed for these allocator optimization data structures to get populated and provide better group scanning order. So, turn it on bu default. prefetch_block_bitmaps mount option is now marked as removed and a new option no_prefetch_block_bitmaps is added to disable block bitmap prefetching. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://lore.kernel.org/r/20210401172129.189766-8-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-09ext4: improve cr 0 / cr 1 group scanningHarshad Shirwadkar1-1/+27
Instead of traversing through groups linearly, scan groups in specific orders at cr 0 and cr 1. At cr 0, we want to find groups that have the largest free order >= the order of the request. So, with this patch, we maintain lists for each possible order and insert each group into a list based on the largest free order in its buddy bitmap. During cr 0 allocation, we traverse these lists in the increasing order of largest free orders. This allows us to find a group with the best available cr 0 match in constant time. If nothing can be found, we fallback to cr 1 immediately. At CR1, the story is slightly different. We want to traverse in the order of increasing average fragment size. For CR1, we maintain a rb tree of groupinfos which is sorted by average fragment size. Instead of traversing linearly, at CR1, we traverse in the order of increasing average fragment size, starting at the most optimal group. This brings down cr 1 search complexity to log(num groups). For cr >= 2, we just perform the linear search as before. Also, in case of lock contention, we intermittently fallback to linear search even in CR 0 and CR 1 cases. This allows us to proceed during the allocation path even in case of high contention. There is an opportunity to do optimization at CR2 too. That's because at CR2 we only consider groups where bb_free counter (number of free blocks) is greater than the request extent size. That's left as future work. All the changes introduced in this patch are protected under a new mount option "mb_optimize_scan". With this patchset, following experiment was performed: Created a highly fragmented disk of size 65TB. The disk had no contiguous 2M regions. Following command was run consecutively for 3 times: time dd if=/dev/urandom of=file bs=2M count=10 Here are the results with and without cr 0/1 optimizations introduced in this patch: |---------+------------------------------+---------------------------| | | Without CR 0/1 Optimizations | With CR 0/1 Optimizations | |---------+------------------------------+---------------------------| | 1st run | 5m1.871s | 2m47.642s | | 2nd run | 2m28.390s | 0m0.611s | | 3rd run | 2m26.530s | 0m1.255s | |---------+------------------------------+---------------------------| Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20210401172129.189766-6-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-09ext4: add ability to return parsed options from parse_optionsHarshad Shirwadkar1-21/+30
Before this patch, the function parse_options() was returning journal_devnum and journal_ioprio variables to the caller. This patch generalizes that interface to allow parse_options to return any parsed options to return back to the caller. In this patch series, it gets used to capture the value of "mb_optimize_scan=%u" mount option. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20210401172129.189766-3-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-05ext4: handle casefolding with encryptionDaniel Rosenberg1-6/+0
This adds support for encryption with casefolding. Since the name on disk is case preserving, and also encrypted, we can no longer just recompute the hash on the fly. Additionally, to avoid leaking extra information from the hash of the unencrypted name, we use siphash via an fscrypt v2 policy. The hash is stored at the end of the directory entry for all entries inside of an encrypted and casefolded directory apart from those that deal with '.' and '..'. This way, the change is backwards compatible with existing ext4 filesystems. [ Changed to advertise this feature via the file: /sys/fs/ext4/features/encrypted_casefold -- TYT ] Signed-off-by: Daniel Rosenberg <drosen@google.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20210319073414.1381041-2-drosen@google.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-21ext4: fix timer use-after-free on failed mountJan Kara1-1/+1
When filesystem mount fails because of corrupted filesystem we first cancel the s_err_report timer reminding fs errors every day and only then we flush s_error_work. However s_error_work may report another fs error and re-arm timer thus resulting in timer use-after-free. Fix the problem by first flushing the work and only after that canceling the s_err_report timer. Reported-by: syzbot+628472a2aac693ab0fcd@syzkaller.appspotmail.com Fixes: 2d01ddc86606 ("ext4: save error info to sb through journal if available") CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210315165906.2175-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-06ext4: shrink race window in ext4_should_retry_alloc()Eric Whitney1-0/+5
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 <enwlinux@gmail.com> Link: https://lore.kernel.org/r/20210218151132.19678-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-02-25Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-3/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Miscellaneous ext4 cleanups and bug fixes. Pretty boring this cycle..." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: add .kunitconfig fragment to enable ext4-specific tests ext: EXT4_KUNIT_TESTS should depend on EXT4_FS instead of selecting it ext4: reset retry counter when ext4_alloc_file_blocks() makes progress ext4: fix potential htree index checksum corruption ext4: factor out htree rep invariant check ext4: Change list_for_each* to list_for_each_entry* ext4: don't try to processed freed blocks until mballoc is initialized ext4: use DEFINE_MUTEX() for mutex lock
2021-02-23Merge tag 'idmapped-mounts-v5.12' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull idmapped mounts from Christian Brauner: "This introduces idmapped mounts which has been in the making for some time. Simply put, different mounts can expose the same file or directory with different ownership. This initial implementation comes with ports for fat, ext4 and with Christoph's port for xfs with more filesystems being actively worked on by independent people and maintainers. Idmapping mounts handle a wide range of long standing use-cases. Here are just a few: - Idmapped mounts make it possible to easily share files between multiple users or multiple machines especially in complex scenarios. For example, idmapped mounts will be used in the implementation of portable home directories in systemd-homed.service(8) where they allow users to move their home directory to an external storage device and use it on multiple computers where they are assigned different uids and gids. This effectively makes it possible to assign random uids and gids at login time. - It is possible to share files from the host with unprivileged containers without having to change ownership permanently through chown(2). - It is possible to idmap a container's rootfs and without having to mangle every file. For example, Chromebooks use it to share the user's Download folder with their unprivileged containers in their Linux subsystem. - It is possible to share files between containers with non-overlapping idmappings. - Filesystem that lack a proper concept of ownership such as fat can use idmapped mounts to implement discretionary access (DAC) permission checking. - They allow users to efficiently changing ownership on a per-mount basis without having to (recursively) chown(2) all files. In contrast to chown (2) changing ownership of large sets of files is instantenous with idmapped mounts. This is especially useful when ownership of a whole root filesystem of a virtual machine or container is changed. With idmapped mounts a single syscall mount_setattr syscall will be sufficient to change the ownership of all files. - Idmapped mounts always take the current ownership into account as idmappings specify what a given uid or gid is supposed to be mapped to. This contrasts with the chown(2) syscall which cannot by itself take the current ownership of the files it changes into account. It simply changes the ownership to the specified uid and gid. This is especially problematic when recursively chown(2)ing a large set of files which is commong with the aforementioned portable home directory and container and vm scenario. - Idmapped mounts allow to change ownership locally, restricting it to specific mounts, and temporarily as the ownership changes only apply as long as the mount exists. Several userspace projects have either already put up patches and pull-requests for this feature or will do so should you decide to pull this: - systemd: In a wide variety of scenarios but especially right away in their implementation of portable home directories. https://systemd.io/HOME_DIRECTORY/ - container runtimes: containerd, runC, LXD:To share data between host and unprivileged containers, unprivileged and privileged containers, etc. The pull request for idmapped mounts support in containerd, the default Kubernetes runtime is already up for quite a while now: https://github.com/containerd/containerd/pull/4734 - The virtio-fs developers and several users have expressed interest in using this feature with virtual machines once virtio-fs is ported. - ChromeOS: Sharing host-directories with unprivileged containers. I've tightly synced with all those projects and all of those listed here have also expressed their need/desire for this feature on the mailing list. For more info on how people use this there's a bunch of talks about this too. Here's just two recent ones: https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf https://fosdem.org/2021/schedule/event/containers_idmap/ This comes with an extensive xfstests suite covering both ext4 and xfs: https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts It covers truncation, creation, opening, xattrs, vfscaps, setid execution, setgid inheritance and more both with idmapped and non-idmapped mounts. It already helped to discover an unrelated xfs setgid inheritance bug which has since been fixed in mainline. It will be sent for inclusion with the xfstests project should you decide to merge this. In order to support per-mount idmappings vfsmounts are marked with user namespaces. The idmapping of the user namespace will be used to map the ids of vfs objects when they are accessed through that mount. By default all vfsmounts are marked with the initial user namespace. The initial user namespace is used to indicate that a mount is not idmapped. All operations behave as before and this is verified in the testsuite. Based on prior discussions we want to attach the whole user namespace and not just a dedicated idmapping struct. This allows us to reuse all the helpers that already exist for dealing with idmappings instead of introducing a whole new range of helpers. In addition, if we decide in the future that we are confident enough to enable unprivileged users to setup idmapped mounts the permission checking can take into account whether the caller is privileged in the user namespace the mount is currently marked with. The user namespace the mount will be marked with can be specified by passing a file descriptor refering to the user namespace as an argument to the new mount_setattr() syscall together with the new MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern of extensibility. The following conditions must be met in order to create an idmapped mount: - The caller must currently have the CAP_SYS_ADMIN capability in the user namespace the underlying filesystem has been mounted in. - The underlying filesystem must support idmapped mounts. - The mount must not already be idmapped. This also implies that the idmapping of a mount cannot be altered once it has been idmapped. - The mount must be a detached/anonymous mount, i.e. it must have been created by calling open_tree() with the OPEN_TREE_CLONE flag and it must not already have been visible in the filesystem. The last two points guarantee easier semantics for userspace and the kernel and make the implementation significantly simpler. By default vfsmounts are marked with the initial user namespace and no behavioral or performance changes are observed. The manpage with a detailed description can be found here: https://git.kernel.org/brauner/man-pages/c/1d7b902e2875a1ff342e036a9f866a995640aea8 In order to support idmapped mounts, filesystems need to be changed and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The patches to convert individual filesystem are not very large or complicated overall as can be seen from the included fat, ext4, and xfs ports. Patches for other filesystems are actively worked on and will be sent out separately. The xfstestsuite can be used to verify that port has been done correctly. The mount_setattr() syscall is motivated independent of the idmapped mounts patches and it's been around since July 2019. One of the most valuable features of the new mount api is the ability to perform mounts based on file descriptors only. Together with the lookup restrictions available in the openat2() RESOLVE_* flag namespace which we added in v5.6 this is the first time we are close to hardened and race-free (e.g. symlinks) mounting and path resolution. While userspace has started porting to the new mount api to mount proper filesystems and create new bind-mounts it is currently not possible to change mount options of an already existing bind mount in the new mount api since the mount_setattr() syscall is missing. With the addition of the mount_setattr() syscall we remove this last restriction and userspace can now fully port to the new mount api, covering every use-case the old mount api could. We also add the crucial ability to recursively change mount options for a whole mount tree, both removing and adding mount options at the same time. This syscall has been requested multiple times by various people and projects. There is a simple tool available at https://github.com/brauner/mount-idmapped that allows to create idmapped mounts so people can play with this patch series. I'll add support for the regular mount binary should you decide to pull this in the following weeks: Here's an example to a simple idmapped mount of another user's home directory: u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt u1001@f2-vm:/$ ls -al /home/ubuntu/ total 28 drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 . drwxr-xr-x 4 root root 4096 Oct 28 04:00 .. -rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile -rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ ls -al /mnt/ total 28 drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 . drwxr-xr-x 29 root root 4096 Oct 28 22:01 .. -rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile -rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ touch /mnt/my-file u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file u1001@f2-vm:/$ ls -al /mnt/my-file -rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file u1001@f2-vm:/$ ls -al /home/ubuntu/my-file -rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file u1001@f2-vm:/$ getfacl /mnt/my-file getfacl: Removing leading '/' from absolute path names # file: mnt/my-file # owner: u1001 # group: u1001 user::rw- user:u1001:rwx group::rw- mask::rwx other::r-- u1001@f2-vm:/$ getfacl /home/ubuntu/my-file getfacl: Removing leading '/' from absolute path names # file: home/ubuntu/my-file # owner: ubuntu # group: ubuntu user::rw- user:ubuntu:rwx group::rw- mask::rwx other::r--" * tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits) xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl xfs: support idmapped mounts ext4: support idmapped mounts fat: handle idmapped mounts tests: add mount_setattr() selftests fs: introduce MOUNT_ATTR_IDMAP fs: add mount_setattr() fs: add attr_flags_to_mnt_flags helper fs: split out functions to hold writers namespace: only take read lock in do_reconfigure_mnt() mount: make {lock,unlock}_mount_hash() static namespace: take lock_mount_hash() directly when changing flags nfs: do not export idmapped mounts overlayfs: do not mount on top of idmapped mounts ecryptfs: do not mount on top of idmapped mounts ima: handle idmapped mounts apparmor: handle idmapped mounts fs: make helpers idmap mount aware exec: handle idmapped mounts would_dump: handle idmapped mounts ...
2021-02-02ext4: don't try to processed freed blocks until mballoc is initializedTheodore Ts'o1-1/+8
If we try to make any changes via the journal between when the journal is initialized, but before the multi-block allocated is initialized, we will end up deferencing a NULL pointer when the journal commit callback function calls ext4_process_freed_data(). The proximate cause of this failure was commit 2d01ddc86606 ("ext4: save error info to sb through journal if available") since file system corruption problems detected before the call to ext4_mb_init() would result in a journal commit before we aborted the mount of the file system.... and we would then trigger the NULL pointer deref. Link: https://lore.kernel.org/r/YAm8qH/0oo2ofSMR@mit.edu Reported-by: Murphy Zhou <jencce.kernel@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-02-02ext4: use DEFINE_MUTEX() for mutex lockZheng Yongjun1-2/+1
mutex lock can be initialized automatically with DEFINE_MUTEX() rather than explicitly calling mutex_init(). Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Link: https://lore.kernel.org/r/20201224132244.30907-1-zhengyongjun3@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-01-27block: use an on-stack bio in blkdev_issue_flushChristoph Hellwig1-1/+1
There is no point in allocating memory for a synchronous flush. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Acked-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24ext4: support idmapped mountsChristian Brauner1-1/+1
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 <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-ext4@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-15Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds1-72/+118
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "A number of bug fixes for ext4: - Fix for the new fast_commit feature - Fix some error handling codepaths in whiteout handling and mountpoint sampling - Fix how we write ext4_error information so it goes through the journal when journalling is active, to avoid races that can lead to lost error information, superblock checksum failures, or DIF/DIX features" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: remove expensive flush on fast commit ext4: fix bug for rename with RENAME_WHITEOUT ext4: fix wrong list_splice in ext4_fc_cleanup ext4: use IS_ERR instead of IS_ERR_OR_NULL and set inode null when IS_ERR ext4: don't leak old mountpoint samples ext4: drop ext4_handle_dirty_super() ext4: fix superblock checksum failure when setting password salt ext4: use sbi instead of EXT4_SB(sb) in ext4_update_super() ext4: save error info to sb through journal if available ext4: protect superblock modifications with a buffer lock ext4: drop sync argument of ext4_commit_super() ext4: combine ext4_handle_error() and save_error_info()
2020-12-24Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-215/+207
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Various bug fixes and cleanups for ext4; no new features this cycle" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (29 commits) ext4: remove unnecessary wbc parameter from ext4_bio_write_page ext4: avoid s_mb_prefetch to be zero in individual scenarios ext4: defer saving error info from atomic context ext4: simplify ext4 error translation ext4: move functions in super.c ext4: make ext4_abort() use __ext4_error() ext4: standardize error message in ext4_protect_reserved_inode() ext4: remove redundant sb checksum recomputation ext4: don't remount read-only with errors=continue on reboot ext4: fix deadlock with fs freezing and EA inodes jbd2: add a helper to find out number of fast commit blocks ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h ext4: fix fall-through warnings for Clang ext4: add docs about fast commit idempotence ext4: remove the unused EXT4_CURRENT_REV macro ext4: fix an IS_ERR() vs NULL check ext4: check for invalid block size early when mounting a file system ext4: fix a memory leak of ext4_free_data ext4: delete nonsensical (commented-out) code inside ext4_xattr_block_set() ext4: update ext4_data_block_valid related comments ...
2020-12-22ext4: use sbi instead of EXT4_SB(sb) in ext4_update_super()Jan Kara1-11/+10
No behavioral change. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20201216101844.22917-6-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22ext4: save error info to sb through journal if availableJan Kara1-26/+75
If journalling is still working at the moment we get to writing error information to the superblock we cannot write directly to the superblock as such write could race with journalled update of the superblock and cause journal checksum failures, writing inconsistent information to the journal or other problems. We cannot journal the superblock directly from the error handling functions as we are running in uncertain context and could deadlock so just punt journalled superblock update to a workqueue. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20201216101844.22917-5-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22ext4: protect superblock modifications with a buffer lockJan Kara1-1/+1
Protect all superblock modifications (including checksum computation) with a superblock buffer lock. That way we are sure computed checksum matches current superblock contents (a mismatch could cause checksum failures in nojournal mode or if an unjournalled superblock update races with a journalled one). Also we avoid modifying superblock contents while it is being written out (which can cause DIF/DIX failures if we are running in nojournal mode). Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20201216101844.22917-4-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22ext4: drop sync argument of ext4_commit_super()Jan Kara1-25/+22
Everybody passes 1 as sync argument of ext4_commit_super(). Just drop it. Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20201216101844.22917-3-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22ext4: combine ext4_handle_error() and save_error_info()Jan Kara1-17/+17
save_error_info() is always called together with ext4_handle_error(). Combine them into a single call and move unconditional bits out of save_error_info() into ext4_handle_error(). Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20201216101844.22917-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22ext4: defer saving error info from atomic contextJan Kara1-37/+83
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 <jack@suse.cz> Link: https://lore.kernel.org/r/20201127113405.26867-8-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: Hillf Danton <hdanton@sina.com> Reported-by: syzbot+9043030c040ce1849a60@syzkaller.appspotmail.com
2020-12-17Merge tag 'f2fs-for-5.11-rc1' of ↵Linus Torvalds1-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "In this round, we've made more work into per-file compression support. For example, F2FS_IOC_GET | SET_COMPRESS_OPTION provides a way to change the algorithm or cluster size per file. F2FS_IOC_COMPRESS | DECOMPRESS_FILE provides a way to compress and decompress the existing normal files manually. There is also a new mount option, compress_mode=fs|user, which can control who compresses the data. Chao also added a checksum feature with a mount option so that we are able to detect any corrupted cluster. In addition, Daniel contributed casefolding with encryption patch, which will be used for Android devices. Summary: Enhancements: - add ioctls and mount option to manage per-file compression feature - support casefolding with encryption - support checksum for compressed cluster - avoid IO starvation by replacing mutex with rwsem - add sysfs, max_io_bytes, to control max bio size Bug fixes: - fix use-after-free issue when compression and fsverity are enabled - fix consistency corruption during fault injection test - fix data offset for lseek - get rid of buffer_head which has 32bits limit in fiemap - fix some bugs in multi-partitions support - fix nat entry count calculation in shrinker - fix some stat information And, we've refactored some logics and fix minor bugs as well" * tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (36 commits) f2fs: compress: fix compression chksum f2fs: fix shift-out-of-bounds in sanity_check_raw_super() f2fs: fix race of pending_pages in decompression f2fs: fix to account inline xattr correctly during recovery f2fs: inline: fix wrong inline inode stat f2fs: inline: correct comment in f2fs_recover_inline_data f2fs: don't check PAGE_SIZE again in sanity_check_raw_super() f2fs: convert to F2FS_*_INO macro f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size f2fs: don't allow any writes on readonly mount f2fs: avoid race condition for shrinker count f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE f2fs: add compress_mode mount option f2fs: Remove unnecessary unlikely() f2fs: init dirty_secmap incorrectly f2fs: remove buffer_head which has 32bits limit f2fs: fix wrong block count instead of bytes f2fs: use new conversion functions between blks and bytes f2fs: rename logical_to_blk and blk_to_logical f2fs: fix kbytes written stat for multi-device case ...
2020-12-17ext4: simplify ext4 error translationJan Kara1-55/+40
We convert errno's to ext4 on-disk format error codes in save_error_info(). Add a function and a bit of macro magic to make this simpler. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20201127113405.26867-7-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-17ext4: move functions in super.cJan Kara1-98/+98
Just move error info related functions in super.c close to ext4_handle_error(). We'll want to combine save_error_info() with ext4_handle_error() and this makes change more obvious and saves a forward declaration as well. No functional change. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20201127113405.26867-6-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-17ext4: make ext4_abort() use __ext4_error()Jan Kara1-62/+22
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 <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20201127113405.26867-5-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-17ext4: remove redundant sb checksum recomputationJan Kara1-2/+0
Superblock is written out either through ext4_commit_super() or through ext4_handle_dirty_super(). In both cases we recompute the checksum so it is not necessary to recompute it after updating superblock free inodes & blocks counters. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20201127113405.26867-3-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-17ext4: don't remount read-only with errors=continue on rebootJan Kara1-8/+6
ext4_handle_error() with errors=continue mount option can accidentally remount the filesystem read-only when the system is rebooting. Fix that. Fixes: 1dc1097ff60e ("ext4: avoid panic during forced reboot") Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Cc: stable@kernel.org Link: https://lore.kernel.org/r/20201127113405.26867-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-17ext4: fix fall-through warnings for ClangGustavo A. R. Silva1-0/+1
In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning by explicitly adding a break statement instead of just letting the code fall through to the next case. Link: https://github.com/KSPP/linux/issues/115 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://lore.kernel.org/r/03497331f088a938d7a728e7a689bd7953139429.1605896059.git.gustavoars@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-17ext4: check for invalid block size early when mounting a file systemTheodore Ts'o1-24/+16
Check for valid block size directly by validating s_log_block_size; we were doing this in two places. First, by calculating blocksize via BLOCK_SIZE << s_log_block_size, and then checking that the blocksize was valid. And then secondly, by checking s_log_block_size directly. The first check is not reliable, and can trigger an UBSAN warning if s_log_block_size on a maliciously corrupted superblock is greater than 22. This is harmless, since the second test will correctly reject the maliciously fuzzed file system, but to make syzbot shut up, and because the two checks are duplicative in any case, delete the blocksize check, and move the s_log_block_size earlier in ext4_fill_super(). Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reported-by: syzbot+345b75652b1d24227443@syzkaller.appspotmail.com
2020-12-16Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-blockLinus Torvalds1-12/+6
Pull block updates from Jens Axboe: "Another series of killing more code than what is being added, again thanks to Christoph's relentless cleanups and tech debt tackling. This contains: - blk-iocost improvements (Baolin Wang) - part0 iostat fix (Jeffle Xu) - Disable iopoll for split bios (Jeffle Xu) - block tracepoint cleanups (Christoph Hellwig) - Merging of struct block_device and hd_struct (Christoph Hellwig) - Rework/cleanup of how block device sizes are updated (Christoph Hellwig) - Simplification of gendisk lookup and removal of block device aliasing (Christoph Hellwig) - Block device ioctl cleanups (Christoph Hellwig) - Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig) - Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig) - sbitmap improvements (Pavel Begunkov) - Hybrid polling fix (Pavel Begunkov) - bvec iteration improvements (Pavel Begunkov) - Zone revalidation fixes (Damien Le Moal) - blk-throttle limit fix (Yu Kuai) - Various little fixes" * tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits) blk-mq: fix msec comment from micro to milli seconds blk-mq: update arg in comment of blk_mq_map_queue blk-mq: add helper allocating tagset->tags Revert "block: Fix a lockdep complaint triggered by request queue flushing" nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class blk-mq: add new API of blk_mq_hctx_set_fq_lock_class block: disable iopoll for split bio block: Improve blk_revalidate_disk_zones() checks sbitmap: simplify wrap check sbitmap: replace CAS with atomic and sbitmap: remove swap_lock sbitmap: optimise sbitmap_deferred_clear() blk-mq: skip hybrid polling if iopoll doesn't spin blk-iocost: Factor out the base vrate change into a separate function blk-iocost: Factor out the active iocgs' state check into a separate function blk-iocost: Move the usage ratio calculation to the correct place blk-iocost: Remove unnecessary advance declaration blk-iocost: Fix some typos in comments blktrace: fix up a kerneldoc comment block: remove the request_queue to argument request based tracepoints ...
2020-12-03ext4: use ASSERT() to replace J_ASSERT()Chunguang Xu1-1/+1
There are currently multiple forms of assertion, such as J_ASSERT(). J_ASEERT() is provided for the jbd module, which is a public module. Maybe we should use custom ASSERT() like other file systems, such as xfs, which would be better. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/1604764698-4269-1-git-send-email-brookxu@tencent.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-03ext4: print quota journalling mode on (re-)mountRoman Anufriev1-3/+20
Right now, it is hard to understand which quota journalling type is enabled: you need to be quite familiar with kernel code and trace it or really understand what different combinations of fs flags/mount options lead to. This patch adds printing of current quota jounalling mode on each mount/remount, thus making it easier to check it at a glance/in autotests. The semantics is similar to ext4 data journalling modes: * journalled - quota configured, journalling will be enabled * writeback - quota configured, journalling won't be enabled * none - quota isn't configured * disabled - kernel compiled without CONFIG_QUOTA feature Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/1603336860-16153-2-git-send-email-dotdot@yandex-team.ru Signed-off-by: Roman Anufriev <dotdot@yandex-team.ru> Signed-off-by: Theodore Ts'o <tytso@mit.edu>