summaryrefslogtreecommitdiffstats
path: root/fs/nilfs2/segment.c (follow)
Commit message (Collapse)AuthorAgeFilesLines
* Merge tag 'mm-nonmm-stable-2024-09-21-07-52' of ↵Linus Torvalds2024-09-211-106/+128
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Many singleton patches - please see the various changelogs for details. Quite a lot of nilfs2 work this time around. Notable patch series in this pull request are: - "mul_u64_u64_div_u64: new implementation" by Nicolas Pitre, with assistance from Uwe Kleine-König. Reimplement mul_u64_u64_div_u64() to provide (much) more accurate results. The current implementation was causing Uwe some issues in the PWM drivers. - "xz: Updates to license, filters, and compression options" from Lasse Collin. Miscellaneous maintenance and kinor feature work to the xz decompressor. - "Fix some GDB command error and add some GDB commands" from Kuan-Ying Lee. Fixes and enhancements to the gdb scripts. - "treewide: add missing MODULE_DESCRIPTION() macros" from Jeff Johnson. Adds lots of MODULE_DESCRIPTIONs, thus fixing lots of warnings about this. - "nilfs2: add support for some common ioctls" from Ryusuke Konishi. Adds various commonly-available ioctls to nilfs2. - "This series fixes a number of formatting issues in kernel doc comments" from Ryusuke Konishi does that. - "nilfs2: prevent unexpected ENOENT propagation" from Ryusuke Konishi. Fix issues where -ENOENT was being unintentionally and inappropriately returned to userspace. - "nilfs2: assorted cleanups" from Huang Xiaojia. - "nilfs2: fix potential issues with empty b-tree nodes" from Ryusuke Konishi fixes some issues which can occur on corrupted nilfs2 filesystems. - "scripts/decode_stacktrace.sh: improve error reporting and usability" from Luca Ceresoli does those things" * tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (103 commits) list: test: increase coverage of list_test_list_replace*() list: test: fix tests for list_cut_position() proc: use __auto_type more treewide: correct the typo 'retun' ocfs2: cleanup return value and mlog in ocfs2_global_read_info() nilfs2: remove duplicate 'unlikely()' usage nilfs2: fix potential oob read in nilfs_btree_check_delete() nilfs2: determine empty node blocks as corrupted nilfs2: fix potential null-ptr-deref in nilfs_btree_insert() user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation tools/mm: rm thp_swap_allocator_test when make clean squashfs: fix percpu address space issues in decompressor_multi_percpu.c lib: glob.c: added null check for character class nilfs2: refactor nilfs_segctor_thread() nilfs2: use kthread_create and kthread_stop for the log writer thread nilfs2: remove sc_timer_task nilfs2: do not repair reserved inode bitmap in nilfs_new_inode() nilfs2: eliminate the shared counter and spinlock for i_generation nilfs2: separate inode type information from i_state field nilfs2: use the BITS_PER_LONG macro ...
| * nilfs2: refactor nilfs_segctor_thread()Ryusuke Konishi2024-09-021-45/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Simplify nilfs_segctor_thread(), the main loop function of the log writer thread, to make the basic structure easier to understand. In particular, the acquisition and release of the sc_state_lock spinlock was scattered throughout the function, so extract the determination of whether log writing is required into a helper function and make the spinlock lock sections clearer. Link: https://lkml.kernel.org/r/20240826174116.5008-9-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Huang Xiaojia <huangxiaojia2@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * nilfs2: use kthread_create and kthread_stop for the log writer threadRyusuke Konishi2024-09-021-51/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By using kthread_create() and kthread_stop() to start and stop the log writer thread, eliminate custom thread start and stop helpers, as well as the wait queue "sc_wait_task" on the "nilfs_sc_info" struct and NILFS_SEGCTOR_QUIT flag that exist only to implement them. Also, update the kernel doc comments of the changed functions as appropriate. Link: https://lkml.kernel.org/r/20240826174116.5008-8-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Huang Xiaojia <huangxiaojia2@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * nilfs2: remove sc_timer_taskRyusuke Konishi2024-09-021-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit f5d4e04634c9 ("nilfs2: fix use-after-free of timer for log writer thread") is applied, nilfs_construct_timeout(), which is called by a timer and wakes up the log writer thread, is never called after the log writer thread has terminated. As a result, the member variable "sc_timer_task" of the "nilfs_sc_info" structure, which was added when timer_setup() was adopted to retain a reference to the log writer thread's task even after it had terminated, is no longer needed, as it should be; we can simply use "sc_task" instead, which holds a reference to the log writer thread's task for its lifetime. So, eliminate "sc_timer_task" by this means. Link: https://lkml.kernel.org/r/20240826174116.5008-7-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Huang Xiaojia <huangxiaojia2@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * nilfs2: separate inode type information from i_state fieldRyusuke Konishi2024-09-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In nilfs_iget_locked() and nilfs_ilookup(), which are used to find or obtain nilfs2 inodes, the nilfs_iget_args structure used to identify inodes has type information divided into multiple booleans, making type determination complicated. Simplify inode type determination by consolidating inode type information into an unsigned integer represented by a comibination of flags and by separating the type identification information for on-memory inodes from the i_state member in the nilfs_inode_info structure. Link: https://lkml.kernel.org/r/20240826174116.5008-4-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Huang Xiaojia <huangxiaojia2@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * nilfs2: do not propagate ENOENT error from sufile during GCRyusuke Konishi2024-09-021-8/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | nilfs_sufile_freev(), which is used to free segments in GC, aborts with -ENOENT if the target segment usage is on a hole block. This error only occurs if one of the segment numbers to be freed passed by the GC ioctl is invalid, so return -EINVAL instead. To avoid impairing readability, introduce a wrapper function that encapsulates error handling including the error code conversion (and error message output). Link: https://lkml.kernel.org/r/20240821154627.11848-5-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | nilfs2: fix state management in error path of log writing functionRyusuke Konishi2024-09-021-4/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit a694291a6211 ("nilfs2: separate wait function from nilfs_segctor_write") was applied, the log writing function nilfs_segctor_do_construct() was able to issue I/O requests continuously even if user data blocks were split into multiple logs across segments, but two potential flaws were introduced in its error handling. First, if nilfs_segctor_begin_construction() fails while creating the second or subsequent logs, the log writing function returns without calling nilfs_segctor_abort_construction(), so the writeback flag set on pages/folios will remain uncleared. This causes page cache operations to hang waiting for the writeback flag. For example, truncate_inode_pages_final(), which is called via nilfs_evict_inode() when an inode is evicted from memory, will hang. Second, the NILFS_I_COLLECTED flag set on normal inodes remain uncleared. As a result, if the next log write involves checkpoint creation, that's fine, but if a partial log write is performed that does not, inodes with NILFS_I_COLLECTED set are erroneously removed from the "sc_dirty_files" list, and their data and b-tree blocks may not be written to the device, corrupting the block mapping. Fix these issues by uniformly calling nilfs_segctor_abort_construction() on failure of each step in the loop in nilfs_segctor_do_construct(), having it clean up logs and segment usages according to progress, and correcting the conditions for calling nilfs_redirty_inodes() to ensure that the NILFS_I_COLLECTED flag is cleared. Link: https://lkml.kernel.org/r/20240814101119.4070-1-konishi.ryusuke@gmail.com Fixes: a694291a6211 ("nilfs2: separate wait function from nilfs_segctor_write") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: avoid undefined behavior in nilfs_cnt32_ge macroRyusuke Konishi2024-07-051-1/+1
| | | | | | | | | | | | | | | | | | | | According to the C standard 3.4.3p3, the result of signed integer overflow is undefined. The macro nilfs_cnt32_ge(), which compares two sequence numbers, uses signed integer subtraction that can overflow, and therefore the result of the calculation may differ from what is expected due to undefined behavior in different environments. Similar to an earlier change to the jiffies-related comparison macros in commit 5a581b367b5d ("jiffies: Avoid undefined behavior from signed overflow"), avoid this potential issue by changing the definition of the macro to perform the subtraction as unsigned integers, then cast the result to a signed integer for comparison. Link: https://lkml.kernel.org/r/20130727225828.GA11864@linux.vnet.ibm.com Link: https://lkml.kernel.org/r/20240702183512.6390-1-konishi.ryusuke@gmail.com Fixes: 9ff05123e3bf ("nilfs2: segment constructor") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: do not call inode_attach_wb() directlyRyusuke Konishi2024-06-251-2/+2
| | | | | | | | | | | | | | Call mark_buffer_dirty() for segment summary and super root block buffers on the backing device's page cache, thereby indirectly calling inode_attach_wb(). Then remove the no longer needed call to inode_attach_wb() in nilfs_attach_log_writer(), resolving the concern about its layer-violating use. Link: https://lkml.kernel.org/r/20240610160029.7673-3-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: prepare backing device folios for writing after adding checksumsRyusuke Konishi2024-06-251-33/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "nilfs2: eliminate the call to inode_attach_wb()". This series eliminates the inode_attach_wb() call from nilfs2, which was introduced as a workaround for a kernel bug but is suspected of layer violation (in fact, it is undesirable since it exposes a reference to the backing device). Removal of the inode_attach_wb() call is done by simply using mark_buffer_dirty() on the backing device's buffers. To use it safely, this series will prepare it in patch 1/2, and perform the replacement itself in patch 2/2. This patch (of 2): In preparation for inode_attach_wb(), which is currently called when attaching the log writer, to be done via mark_buffer_dirty(), change the order of preparation for log writing. Specifically, the function call that adds checksums to segment summary and super root blocks, which correspond to the log header and trailer, is made before starting writeback of folios containing those blocks. The current steps are as follows: 1. Put the folios of segment summary blocks in writeback state. 2. Put the folios of data blocks, metadata file blocks, and btree node blocks (collectively called payload blocks) into writeback state. 3. Put the super root block folio in writeback state. 4. Add checksums. Change these as follows: 1. Put the folios of payload blocks in writeback state. 2. Add checksums. 3. Put the folios of segment summary blocks in writeback state. 4. Put the super root block folio in writeback state. In this order, the contents of segment summaries and super root block that directly use buffer/folio of the backing device can be determined including the addition of checksums, before preparing to write. Step (1), which puts the payload block folios in writeback state, is performed first because if there are memory-mapped data blocks, a valid checksum can only be calculated after step (1). Link: https://lkml.kernel.org/r/20240610160029.7673-2-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix potential kernel bug due to lack of writeback flag waitingRyusuke Konishi2024-06-061-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Destructive writes to a block device on which nilfs2 is mounted can cause a kernel bug in the folio/page writeback start routine or writeback end routine (__folio_start_writeback in the log below): kernel BUG at mm/page-writeback.c:3070! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI ... RIP: 0010:__folio_start_writeback+0xbaa/0x10e0 Code: 25 ff 0f 00 00 0f 84 18 01 00 00 e8 40 ca c6 ff e9 17 f6 ff ff e8 36 ca c6 ff 4c 89 f7 48 c7 c6 80 c0 12 84 e8 e7 b3 0f 00 90 <0f> 0b e8 1f ca c6 ff 4c 89 f7 48 c7 c6 a0 c6 12 84 e8 d0 b3 0f 00 ... Call Trace: <TASK> nilfs_segctor_do_construct+0x4654/0x69d0 [nilfs2] nilfs_segctor_construct+0x181/0x6b0 [nilfs2] nilfs_segctor_thread+0x548/0x11c0 [nilfs2] kthread+0x2f0/0x390 ret_from_fork+0x4b/0x80 ret_from_fork_asm+0x1a/0x30 </TASK> This is because when the log writer starts a writeback for segment summary blocks or a super root block that use the backing device's page cache, it does not wait for the ongoing folio/page writeback, resulting in an inconsistent writeback state. Fix this issue by waiting for ongoing writebacks when putting folios/pages on the backing device into writeback state. Link: https://lkml.kernel.org/r/20240530141556.4411-1-konishi.ryusuke@gmail.com Fixes: 9ff05123e3bf ("nilfs2: segment constructor") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix potential hang in nilfs_detach_log_writer()Ryusuke Konishi2024-05-241-3/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Syzbot has reported a potential hang in nilfs_detach_log_writer() called during nilfs2 unmount. Analysis revealed that this is because nilfs_segctor_sync(), which synchronizes with the log writer thread, can be called after nilfs_segctor_destroy() terminates that thread, as shown in the call trace below: nilfs_detach_log_writer nilfs_segctor_destroy nilfs_segctor_kill_thread --> Shut down log writer thread flush_work nilfs_iput_work_func nilfs_dispose_list iput nilfs_evict_inode nilfs_transaction_commit nilfs_construct_segment (if inode needs sync) nilfs_segctor_sync --> Attempt to synchronize with log writer thread *** DEADLOCK *** Fix this issue by changing nilfs_segctor_sync() so that the log writer thread returns normally without synchronizing after it terminates, and by forcing tasks that are already waiting to complete once after the thread terminates. The skipped inode metadata flushout will then be processed together in the subsequent cleanup work in nilfs_segctor_destroy(). Link: https://lkml.kernel.org/r/20240520132621.4054-4-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+e3973c409251e136fdd0@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e3973c409251e136fdd0 Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Cc: "Bai, Shuangpeng" <sjb7183@psu.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix unexpected freezing of nilfs_segctor_sync()Ryusuke Konishi2024-05-241-4/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A potential and reproducible race issue has been identified where nilfs_segctor_sync() would block even after the log writer thread writes a checkpoint, unless there is an interrupt or other trigger to resume log writing. This turned out to be because, depending on the execution timing of the log writer thread running in parallel, the log writer thread may skip responding to nilfs_segctor_sync(), which causes a call to schedule() waiting for completion within nilfs_segctor_sync() to lose the opportunity to wake up. The reason why waking up the task waiting in nilfs_segctor_sync() may be skipped is that updating the request generation issued using a shared sequence counter and adding an wait queue entry to the request wait queue to the log writer, are not done atomically. There is a possibility that log writing and request completion notification by nilfs_segctor_wakeup() may occur between the two operations, and in that case, the wait queue entry is not yet visible to nilfs_segctor_wakeup() and the wake-up of nilfs_segctor_sync() will be carried over until the next request occurs. Fix this issue by performing these two operations simultaneously within the lock section of sc_state_lock. Also, following the memory barrier guidelines for event waiting loops, move the call to set_current_state() in the same location into the event waiting loop to ensure that a memory barrier is inserted just before the event condition determination. Link: https://lkml.kernel.org/r/20240520132621.4054-3-konishi.ryusuke@gmail.com Fixes: 9ff05123e3bf ("nilfs2: segment constructor") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Cc: "Bai, Shuangpeng" <sjb7183@psu.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix use-after-free of timer for log writer threadRyusuke Konishi2024-05-241-6/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "nilfs2: fix log writer related issues". This bug fix series covers three nilfs2 log writer-related issues, including a timer use-after-free issue and potential deadlock issue on unmount, and a potential freeze issue in event synchronization found during their analysis. Details are described in each commit log. This patch (of 3): A use-after-free issue has been reported regarding the timer sc_timer on the nilfs_sc_info structure. The problem is that even though it is used to wake up a sleeping log writer thread, sc_timer is not shut down until the nilfs_sc_info structure is about to be freed, and is used regardless of the thread's lifetime. Fix this issue by limiting the use of sc_timer only while the log writer thread is alive. Link: https://lkml.kernel.org/r/20240520132621.4054-1-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/20240520132621.4054-2-konishi.ryusuke@gmail.com Fixes: fdce895ea5dd ("nilfs2: change sc_timer from a pointer to an embedded one in struct nilfs_sc_info") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: "Bai, Shuangpeng" <sjb7183@psu.edu> Closes: https://groups.google.com/g/syzkaller/c/MK_LYqtt8ko/m/8rgdWeseAwAJ Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'pull-bd_inode-1' of ↵Linus Torvalds2024-05-211-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull bdev bd_inode updates from Al Viro: "Replacement of bdev->bd_inode with sane(r) set of primitives by me and Yu Kuai" * tag 'pull-bd_inode-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: RIP ->bd_inode dasd_format(): killing the last remaining user of ->bd_inode nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inode block/bdev.c: use the knowledge of inode/bdev coallocation gfs2: more obvious initializations of mapping->host fs/buffer.c: massage the remaining users of ->bd_inode to ->bd_mapping blk_ioctl_{discard,zeroout}(): we only want ->bd_inode->i_mapping here... grow_dev_folio(): we only want ->bd_inode->i_mapping there use ->bd_mapping instead of ->bd_inode->i_mapping block_device: add a pointer to struct address_space (page cache of bdev) missing helpers: bdev_unhash(), bdev_drop() block: move two helpers into bdev.c block2mtd: prevent direct access of bd_inode dm-vdo: use bdev_nr_bytes(bdev) instead of i_size_read(bdev->bd_inode) blkdev_write_iter(): saner way to get inode and bdev bcachefs: remove dead function bdev_sectors() ext4: remove block_device_ejected() erofs_buf: store address_space instead of inode erofs: switch erofs_bread() to passing offset instead of block number
| * nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inodeAl Viro2024-05-031-1/+1
| | | | | | | | | | | | | | | | | | I suspect that inode_attach_wb() use is rather unidiomatic, but that's a separate story - in any case, its use is a few times per mount *and* the route by which we access that inode is "the host of address_space a page belongs to". Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | nilfs2: remove calls to folio_set_error() and folio_clear_error()Matthew Wilcox (Oracle)2024-05-121-7/+1
|/ | | | | | | | | | | | | | Nobody checks this flag on nilfs2 folios, stop setting and clearing it. That lets us simplify nilfs_end_folio_io() slightly. Link: https://lkml.kernel.org/r/20240420025029.2166544-17-willy@infradead.org Link: https://lkml.kernel.org/r/20240430050901.3239-1-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: kernel test robot <lkp@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: localize highmem mapping for checkpoint finalization within cpfileRyusuke Konishi2024-02-231-46/+5
| | | | | | | | | | | | | | Move the checkpoint finalization routine to the cpfile side, and make the page mapping local and temporary. And use kmap_local instead of kmap to access the checkpoint entry page when finalizing a checkpoint. In this conversion, some of the information on the checkpoint entry being rewritten is passed through the arguments of the newly added method nilfs_cpfile_finalize_checkpoint(). Link: https://lkml.kernel.org/r/20240122140202.6950-13-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: localize highmem mapping for checkpoint creation within cpfileRyusuke Konishi2024-02-231-29/+2
| | | | | | | | | | | | In order to convert kmap() used in cpfile to kmap_local, first move the checkpoint creation routine, which is one of the places where kmap is used, to the cpfile side and make the page mapping local and temporary. And use kmap_local instead of kmap to access the checkpoint entry page (and header block page) when generating a checkpoint. Link: https://lkml.kernel.org/r/20240122140202.6950-12-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert ifile to use kmap_localRyusuke Konishi2024-02-231-1/+1
| | | | | | | | | | | | | Convert deprecated kmap() and kmap_atomic() to use kmap_local for the ifile metadata file used to manage disk inodes. In some usages, calls to kmap_local and kunmap_local are split into different helpers, but those usages can be safely changed to local thread kmap. Link: https://lkml.kernel.org/r/20240122140202.6950-11-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: move nilfs_bmap_write call out of nilfs_write_inode_commonRyusuke Konishi2024-02-231-8/+39
| | | | | | | | | | | | | | | | | | | Before converting the disk inode management metadata file ifile, the call to nilfs_bmap_write(), the i_device_code setting, and the zero-fill code for inodes on the super root block are moved from nilfs_write_inode_common() to its callers. This cleanup simplifies the role and arguments of nilfs_write_inode_common() and collects calls to nilfs_bmap_write() to the log writing code. Also, add and use a new helper nilfs_write_root_mdt_inode() to avoid code duplication in the data export routine nilfs_segctor_fill_in_super_root() to the super root block's buffer. Link: https://lkml.kernel.org/r/20240122140202.6950-9-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix potential bug in end_buffer_async_writeRyusuke Konishi2024-02-081-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to a syzbot report, end_buffer_async_write(), which handles the completion of block device writes, may detect abnormal condition of the buffer async_write flag and cause a BUG_ON failure when using nilfs2. Nilfs2 itself does not use end_buffer_async_write(). But, the async_write flag is now used as a marker by commit 7f42ec394156 ("nilfs2: fix issue with race condition of competition between segments for dirty blocks") as a means of resolving double list insertion of dirty blocks in nilfs_lookup_dirty_data_buffers() and nilfs_lookup_node_buffers() and the resulting crash. This modification is safe as long as it is used for file data and b-tree node blocks where the page caches are independent. However, it was irrelevant and redundant to also introduce async_write for segment summary and super root blocks that share buffers with the backing device. This led to the possibility that the BUG_ON check in end_buffer_async_write would fail as described above, if independent writebacks of the backing device occurred in parallel. The use of async_write for segment summary buffers has already been removed in a previous change. Fix this issue by removing the manipulation of the async_write flag for the remaining super root block buffer. Link: https://lkml.kernel.org/r/20240203161645.4992-1-konishi.ryusuke@gmail.com Fixes: 7f42ec394156 ("nilfs2: fix issue with race condition of competition between segments for dirty blocks") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+5c04210f7c7f897c1e7f@syzkaller.appspotmail.com Closes: https://lkml.kernel.org/r/00000000000019a97c05fd42f8c8@google.com Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: add missing set_freezable() for freezable kthreadKevin Hao2023-12-291-0/+1
| | | | | | | | | | | | The kernel thread function nilfs_segctor_thread() invokes the try_to_freeze() in its loop. But all the kernel threads are non-freezable by default. So if we want to make a kernel thread to be freezable, we have to invoke set_freezable() explicitly. Link: https://lkml.kernel.org/r/20231219090918.2329-1-konishi.ryusuke@gmail.com Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert nilfs_segctor_prepare_write to use foliosMatthew Wilcox (Oracle)2023-12-111-29/+29
| | | | | | | | | Use the new folio APIs, saving 17 hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20231114084436.2755-11-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert to __nilfs_clear_folio_dirty()Matthew Wilcox (Oracle)2023-12-111-1/+1
| | | | | | | | | | | All callers now have a folio, so convert to pass a folio. No caller uses the return value, so make it return void. Removes a couple of hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20231114084436.2755-10-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert to nilfs_folio_buffers_clean()Matthew Wilcox (Oracle)2023-12-111-2/+2
| | | | | | | | | | All callers of nilfs_page_buffers_clean() now have a folio, so convert it to take a folio. While I'm at it, make it return a bool. Link: https://lkml.kernel.org/r/20231114084436.2755-6-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert nilfs_segctor_complete_write to use foliosMatthew Wilcox (Oracle)2023-12-111-28/+21
| | | | | | | | | | Use the new folio APIs, saving five calls to compound_head(). This includes the last callers of nilfs_end_page_io(), so remove that too. Link: https://lkml.kernel.org/r/20231114084436.2755-4-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert nilfs_abort_logs to use foliosMatthew Wilcox (Oracle)2023-12-111-14/+14
| | | | | | | | | Use the new folio APIs, saving five hidden calls to compound_head(). Link: https://lkml.kernel.org/r/20231114084436.2755-3-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: add nilfs_end_folio_io()Matthew Wilcox (Oracle)2023-12-111-14/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "nilfs2: Folio conversions for file paths". This series advances page->folio conversions for a wide range of nilfs2, including its file operations, block routines, and the log writer's writeback routines. It doesn't cover large folios support, but it saves a lot of hidden compound_head() calls while preserving the existing support range behavior. The original series in post [1] also covered directory-related page->folio conversions, but that was put on hold because a regression was found in testing, so this is an excerpt from the first half of the original post. [1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org I tested this series in both 32-bit and 64-bit environments, switching between normal and small block sizes. I also reviewed all changes in all patches to ensure they do not break existing behavior. There were no problems. This patch (of 20): This is the folio counterpart of the existing nilfs_end_page_io() which is retained as a wrapper of nilfs_end_folio_io(). Replaces nine hidden calls to compound_head() with one. Link: https://lkml.kernel.org/r/20231114084436.2755-1-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/20231114084436.2755-2-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* buffer: remove folio_create_empty_buffers()Matthew Wilcox (Oracle)2023-10-261-1/+1
| | | | | | | | | | | | With all users converted, remove the old create_empty_buffers() and rename folio_create_empty_buffers() to create_empty_buffers(). Link: https://lkml.kernel.org/r/20231016201114.1928083-28-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Pankaj Raghav <p.raghav@samsung.com> Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert nilfs_lookup_dirty_data_buffers to use ↵Matthew Wilcox (Oracle)2023-10-261-4/+3
| | | | | | | | | | | | | | folio_create_empty_buffers This function was already using a folio, so this update to the new API removes a single folio->page->folio conversion. Link: https://lkml.kernel.org/r/20231016201114.1928083-17-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Pankaj Raghav <p.raghav@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix general protection fault in nilfs_lookup_dirty_data_buffers()Ryusuke Konishi2023-08-211-0/+5
| | | | | | | | | | | | | | | | | | | | | A syzbot stress test reported that create_empty_buffers() called from nilfs_lookup_dirty_data_buffers() can cause a general protection fault. Analysis using its reproducer revealed that the back reference "mapping" from a page/folio has been changed to NULL after dirty page/folio gang lookup in nilfs_lookup_dirty_data_buffers(). Fix this issue by excluding pages/folios from being collected if, after acquiring a lock on each page/folio, its back reference "mapping" differs from the pointer to the address space struct that held the page/folio. Link: https://lkml.kernel.org/r/20230805132038.6435-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+0ad741797f4565e7e2d2@syzkaller.appspotmail.com Closes: https://lkml.kernel.org/r/0000000000002930a705fc32b231@google.com Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix use-after-free of nilfs_root in dirtying inodes via iputRyusuke Konishi2023-08-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During unmount process of nilfs2, nothing holds nilfs_root structure after nilfs2 detaches its writer in nilfs_detach_log_writer(). Previously, nilfs_evict_inode() could cause use-after-free read for nilfs_root if inodes are left in "garbage_list" and released by nilfs_dispose_list at the end of nilfs_detach_log_writer(), and this bug was fixed by commit 9b5a04ac3ad9 ("nilfs2: fix use-after-free bug of nilfs_root in nilfs_evict_inode()"). However, it turned out that there is another possibility of UAF in the call path where mark_inode_dirty_sync() is called from iput(): nilfs_detach_log_writer() nilfs_dispose_list() iput() mark_inode_dirty_sync() __mark_inode_dirty() nilfs_dirty_inode() __nilfs_mark_inode_dirty() nilfs_load_inode_block() --> causes UAF of nilfs_root struct This can happen after commit 0ae45f63d4ef ("vfs: add support for a lazytime mount option"), which changed iput() to call mark_inode_dirty_sync() on its final reference if i_state has I_DIRTY_TIME flag and i_nlink is non-zero. This issue appears after commit 28a65b49eb53 ("nilfs2: do not write dirty data after degenerating to read-only") when using the syzbot reproducer, but the issue has potentially existed before. Fix this issue by adding a "purging flag" to the nilfs structure, setting that flag while disposing the "garbage_list" and checking it in __nilfs_mark_inode_dirty(). Unlike commit 9b5a04ac3ad9 ("nilfs2: fix use-after-free bug of nilfs_root in nilfs_evict_inode()"), this patch does not rely on ns_writer to determine whether to skip operations, so as not to break recovery on mount. The nilfs_salvage_orphan_logs routine dirties the buffer of salvaged data before attaching the log writer, so changing __nilfs_mark_inode_dirty() to skip the operation when ns_writer is NULL will cause recovery write to fail. The purpose of using the cleanup-only flag is to allow for narrowing of such conditions. Link: https://lkml.kernel.org/r/20230728191318.33047-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+74db8b3087f293d3a13a@syzkaller.appspotmail.com Closes: https://lkml.kernel.org/r/000000000000b4e906060113fd63@google.com Fixes: 0ae45f63d4ef ("vfs: add support for a lazytime mount option") Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> # 4.0+ Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix buffer corruption due to concurrent device readsRyusuke Konishi2023-06-191-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As a result of analysis of a syzbot report, it turned out that in three cases where nilfs2 allocates block device buffers directly via sb_getblk, concurrent reads to the device can corrupt the allocated buffers. Nilfs2 uses sb_getblk for segment summary blocks, that make up a log header, and the super root block, that is the trailer, and when moving and writing the second super block after fs resize. In any of these, since the uptodate flag is not set when storing metadata to be written in the allocated buffers, the stored metadata will be overwritten if a device read of the same block occurs concurrently before the write. This causes metadata corruption and misbehavior in the log write itself, causing warnings in nilfs_btree_assign() as reported. Fix these issues by setting an uptodate flag on the buffer head on the first or before modifying each buffer obtained with sb_getblk, and clearing the flag on failure. When setting the uptodate flag, the lock_buffer/unlock_buffer pair is used to perform necessary exclusive control, and the buffer is filled to ensure that uninitialized bytes are not mixed into the data read from others. As for buffers for segment summary blocks, they are filled incrementally, so if the uptodate flag was unset on their allocation, set the flag and zero fill the buffer once at that point. Also, regarding the superblock move routine, the starting point of the memset call to zerofill the block is incorrectly specified, which can cause a buffer overflow on file systems with block sizes greater than 4KiB. In addition, if the superblock is moved within a large block, it is necessary to assume the possibility that the data in the superblock will be destroyed by zero-filling before copying. So fix these potential issues as well. Link: https://lkml.kernel.org/r/20230609035732.20426-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+31837fe952932efc8fb9@syzkaller.appspotmail.com Closes: https://lkml.kernel.org/r/00000000000030000a05e981f475@google.com Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: do not write dirty data after degenerating to read-onlyRyusuke Konishi2023-05-061-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to syzbot's report, mark_buffer_dirty() called from nilfs_segctor_do_construct() outputs a warning with some patterns after nilfs2 detects metadata corruption and degrades to read-only mode. After such read-only degeneration, page cache data may be cleared through nilfs_clear_dirty_page() which may also clear the uptodate flag for their buffer heads. However, even after the degeneration, log writes are still performed by unmount processing etc., which causes mark_buffer_dirty() to be called for buffer heads without the "uptodate" flag and causes the warning. Since any writes should not be done to a read-only file system in the first place, this fixes the warning in mark_buffer_dirty() by letting nilfs_segctor_do_construct() abort early if in read-only mode. This also changes the retry check of nilfs_segctor_write_out() to avoid unnecessary log write retries if it detects -EROFS that nilfs_segctor_do_construct() returned. Link: https://lkml.kernel.org/r/20230427011526.13457-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+2af3bc9585be7f23f290@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=2af3bc9585be7f23f290 Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: initialize unused bytes in segment summary blocksRyusuke Konishi2023-04-181-0/+20
| | | | | | | | | | | | | | | | | | | Syzbot still reports uninit-value in nilfs_add_checksums_on_logs() for KMSAN enabled kernels after applying commit 7397031622e0 ("nilfs2: initialize "struct nilfs_binfo_dat"->bi_pad field"). This is because the unused bytes at the end of each block in segment summaries are not initialized. So this fixes the issue by padding the unused bytes with null bytes. Link: https://lkml.kernel.org/r/20230417173513.12598-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+048585f3f4227bb2b49b@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=048585f3f4227bb2b49b Cc: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread()Ryusuke Konishi2023-04-061-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The finalization of nilfs_segctor_thread() can race with nilfs_segctor_kill_thread() which terminates that thread, potentially causing a use-after-free BUG as KASAN detected. At the end of nilfs_segctor_thread(), it assigns NULL to "sc_task" member of "struct nilfs_sc_info" to indicate the thread has finished, and then notifies nilfs_segctor_kill_thread() of this using waitqueue "sc_wait_task" on the struct nilfs_sc_info. However, here, immediately after the NULL assignment to "sc_task", it is possible that nilfs_segctor_kill_thread() will detect it and return to continue the deallocation, freeing the nilfs_sc_info structure before the thread does the notification. This fixes the issue by protecting the NULL assignment to "sc_task" and its notification, with spinlock "sc_state_lock" of the struct nilfs_sc_info. Since nilfs_segctor_kill_thread() does a final check to see if "sc_task" is NULL with "sc_state_lock" locked, this can eliminate the race. Link: https://lkml.kernel.org/r/20230327175318.8060-1-konishi.ryusuke@gmail.com Reported-by: syzbot+b08ebcc22f8f3e6be43a@syzkaller.appspotmail.com Link: https://lkml.kernel.org/r/00000000000000660d05f7dfa877@google.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert nilfs_lookup_dirty_node_buffers() to use ↵Vishal Moola (Oracle)2023-02-031-8/+7
| | | | | | | | | | | | | filemap_get_folios_tag() Convert function to use folios throughout. This is in preparation for the removal of find_get_pages_range_tag(). This change removes 1 call to compound_head(). Link: https://lkml.kernel.org/r/20230104211448.4804-20-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: convert nilfs_lookup_dirty_data_buffers() to use ↵Vishal Moola (Oracle)2023-02-031-13/+16
| | | | | | | | | | | | | filemap_get_folios_tag() Convert function to use folios throughout. This is in preparation for the removal of find_get_pages_range_tag(). This change removes 4 calls to compound_head(). Link: https://lkml.kernel.org/r/20230104211448.4804-19-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: replace obvious uses of b_page with b_folioMatthew Wilcox (Oracle)2023-01-191-1/+1
| | | | | | | | | | These places just use b_page to get to the buffer's address_space or the index of the page the buffer is in. Link: https://lkml.kernel.org/r/20221215214402.3522366-11-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* treewide: Convert del_timer*() to timer_shutdown*()Steven Rostedt (Google)2022-12-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Due to several bugs caused by timers being re-armed after they are shutdown and just before they are freed, a new state of timers was added called "shutdown". After a timer is set to this state, then it can no longer be re-armed. The following script was run to find all the trivial locations where del_timer() or del_timer_sync() is called in the same function that the object holding the timer is freed. It also ignores any locations where the timer->function is modified between the del_timer*() and the free(), as that is not considered a "trivial" case. This was created by using a coccinelle script and the following commands: $ cat timer.cocci @@ expression ptr, slab; identifier timer, rfield; @@ ( - del_timer(&ptr->timer); + timer_shutdown(&ptr->timer); | - del_timer_sync(&ptr->timer); + timer_shutdown_sync(&ptr->timer); ) ... when strict when != ptr->timer ( kfree_rcu(ptr, rfield); | kmem_cache_free(slab, ptr); | kfree(ptr); ) $ spatch timer.cocci . > /tmp/t.patch $ patch -p1 < /tmp/t.patch Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/ Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ] Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ] Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nilfs2: fix use-after-free bug of ns_writer on remountRyusuke Konishi2022-11-091-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a nilfs2 filesystem is downgraded to read-only due to metadata corruption on disk and is remounted read/write, or if emergency read-only remount is performed, detaching a log writer and synchronizing the filesystem can be done at the same time. In these cases, use-after-free of the log writer (hereinafter nilfs->ns_writer) can happen as shown in the scenario below: Task1 Task2 -------------------------------- ------------------------------ nilfs_construct_segment nilfs_segctor_sync init_wait init_waitqueue_entry add_wait_queue schedule nilfs_remount (R/W remount case) nilfs_attach_log_writer nilfs_detach_log_writer nilfs_segctor_destroy kfree finish_wait _raw_spin_lock_irqsave __raw_spin_lock_irqsave do_raw_spin_lock debug_spin_lock_before <-- use-after-free While Task1 is sleeping, nilfs->ns_writer is freed by Task2. After Task1 waked up, Task1 accesses nilfs->ns_writer which is already freed. This scenario diagram is based on the Shigeru Yoshida's post [1]. This patch fixes the issue by not detaching nilfs->ns_writer on remount so that this UAF race doesn't happen. Along with this change, this patch also inserts a few necessary read-only checks with superblock instance where only the ns_writer pointer was used to check if the filesystem is read-only. Link: https://syzkaller.appspot.com/bug?id=79a4c002e960419ca173d55e863bd09e8112df8b Link: https://lkml.kernel.org/r/20221103141759.1836312-1-syoshida@redhat.com [1] Link: https://lkml.kernel.org/r/20221104142959.28296-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+f816fa82f8783f7a02bb@syzkaller.appspotmail.com Reported-by: Shigeru Yoshida <syoshida@redhat.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'mm-hotfixes-stable-2022-10-11' of ↵Linus Torvalds2022-10-121-4/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc hotfixes from Andrew Morton: "Five hotfixes - three for nilfs2, two for MM. For are cc:stable, one is not" * tag 'mm-hotfixes-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: nilfs2: fix leak of nilfs_root in case of writer thread creation failure nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level() nilfs2: fix use-after-free bug of struct nilfs_root mm/damon/core: initialize damon_target->list in damon_new_target() mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page
| * nilfs2: fix leak of nilfs_root in case of writer thread creation failureRyusuke Konishi2022-10-121-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If nilfs_attach_log_writer() failed to create a log writer thread, it frees a data structure of the log writer without any cleanup. After commit e912a5b66837 ("nilfs2: use root object to get ifile"), this causes a leak of struct nilfs_root, which started to leak an ifile metadata inode and a kobject on that struct. In addition, if the kernel is booted with panic_on_warn, the above ifile metadata inode leak will cause the following panic when the nilfs2 kernel module is removed: kmem_cache_destroy nilfs2_inode_cache: Slab cache still has objects when called from nilfs_destroy_cachep+0x16/0x3a [nilfs2] WARNING: CPU: 8 PID: 1464 at mm/slab_common.c:494 kmem_cache_destroy+0x138/0x140 ... RIP: 0010:kmem_cache_destroy+0x138/0x140 Code: 00 20 00 00 e8 a9 55 d8 ff e9 76 ff ff ff 48 8b 53 60 48 c7 c6 20 70 65 86 48 c7 c7 d8 69 9c 86 48 8b 4c 24 28 e8 ef 71 c7 00 <0f> 0b e9 53 ff ff ff c3 48 81 ff ff 0f 00 00 77 03 31 c0 c3 53 48 ... Call Trace: <TASK> ? nilfs_palloc_freev.cold.24+0x58/0x58 [nilfs2] nilfs_destroy_cachep+0x16/0x3a [nilfs2] exit_nilfs_fs+0xa/0x1b [nilfs2] __x64_sys_delete_module+0x1d9/0x3a0 ? __sanitizer_cov_trace_pc+0x1a/0x50 ? syscall_trace_enter.isra.19+0x119/0x190 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd ... </TASK> Kernel panic - not syncing: panic_on_warn set ... This patch fixes these issues by calling nilfs_detach_log_writer() cleanup function if spawning the log writer thread fails. Link: https://lkml.kernel.org/r/20221007085226.57667-1-konishi.ryusuke@gmail.com Fixes: e912a5b66837 ("nilfs2: use root object to get ifile") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+7381dc4ad60658ca4c05@syzkaller.appspotmail.com Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failureRyusuke Konishi2022-10-121-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If creation or finalization of a checkpoint fails due to anomalies in the checkpoint metadata on disk, a kernel warning is generated. This patch replaces the WARN_ONs by nilfs_error, so that a kernel, booted with panic_on_warn, does not panic. A nilfs_error is appropriate here to handle the abnormal filesystem condition. This also replaces the detected error codes with an I/O error so that neither of the internal error codes is returned to callers. Link: https://lkml.kernel.org/r/20220929123330.19658-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+fbb3e0b24e8dae5a16ee@syzkaller.appspotmail.com Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | nilfs2: remove the unneeded result variableye xingchen2022-10-031-3/+1
|/ | | | | | | | | | | | | Return the value nilfs_segctor_sync() directly instead of storing it in another redundant variable. Link: https://lkml.kernel.org/r/20220831033403.302184-1-ye.xingchen@zte.com.cn Link: https://lkml.kernel.org/r/20220921034803.2476-3-konishi.ryusuke@gmail.com Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Minghao Chi <chi.minghao@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* nilfs2: fix lockdep warnings in page operations for btree nodesRyusuke Konishi2022-04-011-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "nilfs2 lockdep warning fixes". The first two are to resolve the lockdep warning issue, and the last one is the accompanying cleanup and low priority. Based on your comment, this series solves the issue by separating inode object as needed. Since I was worried about the impact of the object composition changes, I tested the series carefully not to cause regressions especially for delicate functions such like disk space reclamation and snapshots. This patch (of 3): If CONFIG_LOCKDEP is enabled, nilfs2 hits lockdep warnings at inode_to_wb() during page/folio operations for btree nodes: WARNING: CPU: 0 PID: 6575 at include/linux/backing-dev.h:269 inode_to_wb include/linux/backing-dev.h:269 [inline] WARNING: CPU: 0 PID: 6575 at include/linux/backing-dev.h:269 folio_account_dirtied mm/page-writeback.c:2460 [inline] WARNING: CPU: 0 PID: 6575 at include/linux/backing-dev.h:269 __folio_mark_dirty+0xa7c/0xe30 mm/page-writeback.c:2509 Modules linked in: ... RIP: 0010:inode_to_wb include/linux/backing-dev.h:269 [inline] RIP: 0010:folio_account_dirtied mm/page-writeback.c:2460 [inline] RIP: 0010:__folio_mark_dirty+0xa7c/0xe30 mm/page-writeback.c:2509 ... Call Trace: __set_page_dirty include/linux/pagemap.h:834 [inline] mark_buffer_dirty+0x4e6/0x650 fs/buffer.c:1145 nilfs_btree_propagate_p fs/nilfs2/btree.c:1889 [inline] nilfs_btree_propagate+0x4ae/0xea0 fs/nilfs2/btree.c:2085 nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337 nilfs_collect_dat_data+0x45/0xd0 fs/nilfs2/segment.c:625 nilfs_segctor_apply_buffers+0x14a/0x470 fs/nilfs2/segment.c:1009 nilfs_segctor_scan_file+0x47a/0x700 fs/nilfs2/segment.c:1048 nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1224 [inline] nilfs_segctor_collect fs/nilfs2/segment.c:1494 [inline] nilfs_segctor_do_construct+0x14f3/0x6c60 fs/nilfs2/segment.c:2036 nilfs_segctor_construct+0x7a7/0xb30 fs/nilfs2/segment.c:2372 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2480 [inline] nilfs_segctor_thread+0x3c3/0xf90 fs/nilfs2/segment.c:2563 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 This is because nilfs2 uses two page caches for each inode and inode->i_mapping never points to one of them, the btree node cache. This causes inode_to_wb(inode) to refer to a different page cache than the caller page/folio operations such like __folio_start_writeback(), __folio_end_writeback(), or __folio_mark_dirty() acquired the lock. This patch resolves the issue by allocating and using an additional inode to hold the page cache of btree nodes. The inode is attached one-to-one to the traditional nilfs2 inode if it requires a block mapping with b-tree. This setup change is in memory only and does not affect the disk format. Link: https://lkml.kernel.org/r/1647867427-30498-1-git-send-email-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/1647867427-30498-2-git-send-email-konishi.ryusuke@gmail.com Link: https://lore.kernel.org/r/YXrYvIo8YRnAOJCj@casper.infradead.org Link: https://lore.kernel.org/r/9a20b33d-b38f-b4a2-4742-c1eb5b8e4d6c@redhat.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Reported-by: syzbot+0d5b462a6f07447991b3@syzkaller.appspotmail.com Reported-by: syzbot+34ef28bb2aeb28724aa0@syzkaller.appspotmail.com Reported-by: Hao Sun <sunhao.th@gmail.com> Reported-by: David Hildenbrand <david@redhat.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nilfs2: remove filenames from file commentsRyusuke Konishi2021-11-091-1/+1
| | | | | | | | | | | | | Remove filenames that are not particularly useful in file comments, and suppress checkpatch warnings WARNING: It's generally not useful to have the filename in the file Link: https://lkml.kernel.org/r/1635151862-11547-3-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Qing Wang <wangqing@vivo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs/nilfs2: fix misspellings using codespell toolLiu xuzhi2021-05-071-2/+2
| | | | | | | | | | | | | | | | | Two typos are found out by codespell tool \ in 2217th and 2254th lines of segment.c: $ codespell ./fs/nilfs2/ ./segment.c:2217 :retured ==> returned ./segment.c:2254: retured ==> returned Fix two typos found by codespell. Link: https://lkml.kernel.org/r/1617864087-8198-1-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Liu xuzhi <liu.xuzhi@zte.com.cn> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs/nilfs2: remove some unused macros to tame gccAlex Shi2020-12-161-5/+0
| | | | | | | | | | | | | | There some macros are unused and cause gcc warning. Remove them. fs/nilfs2/segment.c:137:0: warning: macro "nilfs_cnt32_gt" is not used [-Wunused-macros] fs/nilfs2/segment.c:144:0: warning: macro "nilfs_cnt32_le" is not used [-Wunused-macros] fs/nilfs2/segment.c:143:0: warning: macro "nilfs_cnt32_lt" is not used [-Wunused-macros] Link: https://lkml.kernel.org/r/1607552733-24292-1-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>