kernel/git/stable/linux.git/fs/ext4/inode.c, branch linux-5.5.y

ext4: fix a data race at inode->i_blocks

2020-04-17T14:12:15+00:00

commit 28936b62e71e41600bab319f262ea9f9b1027629 upstream. inode->i_blocks could be accessed concurrently as noticed by KCSAN, BUG: KCSAN: data-race in ext4_do_update_inode [ext4] / inode_add_bytes write to 0xffff9a00d4b982d0 of 8 bytes by task 22100 on cpu 118: inode_add_bytes+0x65/0xf0 __inode_add_bytes at fs/stat.c:689 (inlined by) inode_add_bytes at fs/stat.c:702 ext4_mb_new_blocks+0x418/0xca0 [ext4] ext4_ext_map_blocks+0x1a6b/0x27b0 [ext4] ext4_map_blocks+0x1a9/0x950 [ext4] _ext4_get_block+0xfc/0x270 [ext4] ext4_get_block_unwritten+0x33/0x50 [ext4] __block_write_begin_int+0x22e/0xae0 __block_write_begin+0x39/0x50 ext4_write_begin+0x388/0xb50 [ext4] ext4_da_write_begin+0x35f/0x8f0 [ext4] generic_perform_write+0x15d/0x290 ext4_buffered_write_iter+0x11f/0x210 [ext4] ext4_file_write_iter+0xce/0x9e0 [ext4] new_sync_write+0x29c/0x3b0 __vfs_write+0x92/0xa0 vfs_write+0x103/0x260 ksys_write+0x9d/0x130 __x64_sys_write+0x4c/0x60 do_syscall_64+0x91/0xb05 entry_SYSCALL_64_after_hwframe+0x49/0xbe read to 0xffff9a00d4b982d0 of 8 bytes by task 8 on cpu 65: ext4_do_update_inode+0x4a0/0xf60 [ext4] ext4_inode_blocks_set at fs/ext4/inode.c:4815 ext4_mark_iloc_dirty+0xaf/0x160 [ext4] ext4_mark_inode_dirty+0x129/0x3e0 [ext4] ext4_convert_unwritten_extents+0x253/0x2d0 [ext4] ext4_convert_unwritten_io_end_vec+0xc5/0x150 [ext4] ext4_end_io_rsv_work+0x22c/0x350 [ext4] process_one_work+0x54f/0xb90 worker_thread+0x80/0x5f0 kthread+0x1cd/0x1f0 ret_from_fork+0x27/0x50 4 locks held by kworker/u256:0/8: #0: ffff9a025abc4328 ((wq_completion)ext4-rsv-conversion){+.+.}, at: process_one_work+0x443/0xb90 #1: ffffab5a862dbe20 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}, at: process_one_work+0x443/0xb90 #2: ffff9a025a9d0f58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2] #3: ffff9a00d4b985d8 (&(&ei->i_raw_lock)->rlock){+.+.}, at: ext4_do_update_inode+0xaa/0xf60 [ext4] irq event stamp: 3009267 hardirqs last enabled at (3009267): [] __find_get_block+0x107/0x790 hardirqs last disabled at (3009266): [] __find_get_block+0x49/0x790 softirqs last enabled at (3009230): [] __do_softirq+0x34c/0x57c softirqs last disabled at (3009223): [] irq_exit+0xa2/0xc0 Reported by Kernel Concurrency Sanitizer on: CPU: 65 PID: 8 Comm: kworker/u256:0 Tainted: G L 5.6.0-rc2-next-20200221+ #7 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work [ext4] The plain read is outside of inode->i_lock critical section which results in a data race. Fix it by adding READ_ONCE() there. Link: https://lore.kernel.org/r/20200222043258.2279-1-cai@lca.pw Signed-off-by: Qian Cai Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: rename s_journal_flag_rwsem to s_writepages_rwsem

2020-02-28T16:23:39+00:00

commit bbd55937de8f2754adc5792b0f8e5ff7d9c0420e upstream. In preparation for making s_journal_flag_rwsem synchronize ext4_writepages() with changes to both the EXTENTS and JOURNAL_DATA flags (rather than just JOURNAL_DATA as it does currently), rename it to s_writepages_rwsem. Link: https://lore.kernel.org/r/20200219183047.47417-2-ebiggers@kernel.org Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix a data race in EXT4_I(inode)->i_disksize

2020-02-28T16:23:38+00:00

commit 35df4299a6487f323b0aca120ea3f485dfee2ae3 upstream. EXT4_I(inode)->i_disksize could be accessed concurrently as noticed by KCSAN, BUG: KCSAN: data-race in ext4_write_end [ext4] / ext4_writepages [ext4] write to 0xffff91c6713b00f8 of 8 bytes by task 49268 on cpu 127: ext4_write_end+0x4e3/0x750 [ext4] ext4_update_i_disksize at fs/ext4/ext4.h:3032 (inlined by) ext4_update_inode_size at fs/ext4/ext4.h:3046 (inlined by) ext4_write_end at fs/ext4/inode.c:1287 generic_perform_write+0x208/0x2a0 ext4_buffered_write_iter+0x11f/0x210 [ext4] ext4_file_write_iter+0xce/0x9e0 [ext4] new_sync_write+0x29c/0x3b0 __vfs_write+0x92/0xa0 vfs_write+0x103/0x260 ksys_write+0x9d/0x130 __x64_sys_write+0x4c/0x60 do_syscall_64+0x91/0xb47 entry_SYSCALL_64_after_hwframe+0x49/0xbe read to 0xffff91c6713b00f8 of 8 bytes by task 24872 on cpu 37: ext4_writepages+0x10ac/0x1d00 [ext4] mpage_map_and_submit_extent at fs/ext4/inode.c:2468 (inlined by) ext4_writepages at fs/ext4/inode.c:2772 do_writepages+0x5e/0x130 __writeback_single_inode+0xeb/0xb20 writeback_sb_inodes+0x429/0x900 __writeback_inodes_wb+0xc4/0x150 wb_writeback+0x4bd/0x870 wb_workfn+0x6b4/0x960 process_one_work+0x54c/0xbe0 worker_thread+0x80/0x650 kthread+0x1e0/0x200 ret_from_fork+0x27/0x50 Reported by Kernel Concurrency Sanitizer on: CPU: 37 PID: 24872 Comm: kworker/u261:2 Tainted: G W O L 5.5.0-next-20200204+ #5 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019 Workqueue: writeback wb_workfn (flush-7:0) Since only the read is operating as lockless (outside of the "i_data_sem"), load tearing could introduce a logic bug. Fix it by adding READ_ONCE() for the read and WRITE_ONCE() for the write. Signed-off-by: Qian Cai Link: https://lore.kernel.org/r/1581085751-31793-1-git-send-email-cai@lca.pw Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix checksum errors with indexed dirs

2020-02-19T18:54:03+00:00

commit 48a34311953d921235f4d7bbd2111690d2e469cf upstream. DIR_INDEX has been introduced as a compat ext4 feature. That means that even kernels / tools that don't understand the feature may modify the filesystem. This works because for kernels not understanding indexed dir format, internal htree nodes appear just as empty directory entries. Index dir aware kernels then check the htree structure is still consistent before using the data. This all worked reasonably well until metadata checksums were introduced. The problem is that these effectively made DIR_INDEX only ro-compatible because internal htree nodes store checksums in a different place than normal directory blocks. Thus any modification ignorant to DIR_INDEX (or just clearing EXT4_INDEX_FL from the inode) will effectively cause checksum mismatch and trigger kernel errors. So we have to be more careful when dealing with indexed directories on filesystems with checksumming enabled. 1) We just disallow loading any directory inodes with EXT4_INDEX_FL when DIR_INDEX is not enabled. This is harsh but it should be very rare (it means someone disabled DIR_INDEX on existing filesystem and didn't run e2fsck), e2fsck can fix the problem, and we don't want to answer the difficult question: "Should we rather corrupt the directory more or should we ignore that DIR_INDEX feature is not set?" 2) When we find out htree structure is corrupted (but the filesystem and the directory should in support htrees), we continue just ignoring htree information for reading but we refuse to add new entries to the directory to avoid corrupting it more. Link: https://lore.kernel.org/r/20200210144316.22081-1-jack@suse.cz Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes") Reviewed-by: Andreas Dilger Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2019-12-22T18:41:48+00:00

Pull ext4 bug fixes from Ted Ts'o: "Ext4 bug fixes, including a regression fix" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: clarify impact of 'commit' mount option ext4: fix unused-but-set-variable warning in ext4_add_entry() jbd2: fix kernel-doc notation warning ext4: use RCU API in debug_print_tree ext4: validate the debug_want_extra_isize mount option at parse time ext4: reserve revoke credits in __ext4_new_inode ext4: unlock on error in ext4_expand_extra_isize() ext4: optimize __ext4_check_dir_entry() ext4: check for directory entries too close to block end ext4: fix ext4_empty_dir() for directories with holes

ext4: unlock on error in ext4_expand_extra_isize()

2019-12-14T22:31:23+00:00

We need to unlock the xattr before returning on this error path. Cc: stable@kernel.org # 4.13 Fixes: c03b45b853f5 ("ext4, project: expand inode extra size if possible") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/20191213185010.6k7yl2tck3wlsdkt@kili.mountain Signed-off-by: Theodore Ts'o

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

2019-11-30T18:53:02+00:00

Pull ext4 updates from Ted Ts'o: "This merge window saw the the following new featuers added to ext4: - Direct I/O via iomap (required the iomap-for-next branch from Darrick as a prereq). - Support for using dioread-nolock where the block size < page size. - Support for encryption for file systems where the block size < page size. - Rework of journal credits handling so a revoke-heavy workload will not cause the journal to run out of space. - Replace bit-spinlocks with spinlocks in jbd2 Also included were some bug fixes and cleanups, mostly to clean up corner cases from fuzzed file systems and error path handling" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (59 commits) ext4: work around deleting a file with i_nlink == 0 safely ext4: add more paranoia checking in ext4_expand_extra_isize handling jbd2: make jbd2_handle_buffer_credits() handle reserved handles ext4: fix a bug in ext4_wait_for_tail_page_commit ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails ext4: code cleanup for get_next_id ext4: fix leak of quota reservations ext4: remove unused variable warning in parse_options() ext4: Enable encryption for subpage-sized blocks fs/buffer.c: support fscrypt in block_read_full_page() ext4: Add error handling for io_end_vec struct allocation jbd2: Fine tune estimate of necessary descriptor blocks jbd2: Provide trace event for handle restarts ext4: Reserve revoke credits for freed blocks jbd2: Make credit checking more strict jbd2: Rename h_buffer_credits to h_total_credits jbd2: Reserve space for revoke descriptor blocks jbd2: Drop jbd2_space_needed() jbd2: Account descriptor blocks into t_outstanding_credits jbd2: Factor out common parts of stopping and restarting a handle ...

Merge tag 'iomap-5.5-merge-11' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2019-11-30T18:44:49+00:00

Pull iomap updates from Darrick Wong: "In this release, we hoisted as much of XFS' writeback code into iomap as was practicable, refactored the unshare file data function, added the ability to perform buffered io copy on write, and tweaked various parts of the directio implementation as needed to port ext4's directio code (that will be a separate pull). Summary: - Make iomap_dio_rw callers explicitly tell us if they want us to wait - Port the xfs writeback code to iomap to complete the buffered io library functions - Refactor the unshare code to share common pieces - Add support for performing copy on write with buffered writes - Other minor fixes - Fix unchecked return in iomap_bmap - Fix a type casting bug in a ternary statement in iomap_dio_bio_actor - Improve tracepoints for easier diagnostic ability - Fix pipe page leakage in directio reads" * tag 'iomap-5.5-merge-11' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (31 commits) iomap: Fix pipe page leakage during splicing iomap: trace iomap_appply results iomap: fix return value of iomap_dio_bio_actor on 32bit systems iomap: iomap_bmap should check iomap_apply return value iomap: Fix overflow in iomap_page_mkwrite fs/iomap: remove redundant check in iomap_dio_rw() iomap: use a srcmap for a read-modify-write I/O iomap: renumber IOMAP_HOLE to 0 iomap: use write_begin to read pages to unshare iomap: move the zeroing case out of iomap_read_page_sync iomap: ignore non-shared or non-data blocks in xfs_file_dirty iomap: always use AOP_FLAG_NOFS in iomap_write_begin iomap: remove the unused iomap argument to __iomap_write_end iomap: better document the IOMAP_F_* flags iomap: enhance writeback error message iomap: pass a struct page to iomap_finish_page_writeback iomap: cleanup iomap_ioend_compare iomap: move struct iomap_page out of iomap.h iomap: warn on inline maps in iomap_writepage_map iomap: lift the xfs writeback code to iomap ...

Merge branch 'tt/misc' into dev

2019-11-19T17:25:42+00:00

ext4: add more paranoia checking in ext4_expand_extra_isize handling

2019-11-19T17:24:55+00:00

It's possible to specify a non-zero s_want_extra_isize via debugging option, and this can cause bad things(tm) to happen when using a file system with an inode size of 128 bytes. Add better checking when the file system is mounted, as well as when we are actually doing the trying to do the inode expansion. Link: https://lore.kernel.org/r/20191110121510.GH23325@mit.edu Reported-by: syzbot+f8d6f8386ceacdbfff57@syzkaller.appspotmail.com Reported-by: syzbot+33d7ea72e47de3bdf4e1@syzkaller.appspotmail.com Reported-by: syzbot+44b6763edfc17144296f@syzkaller.appspotmail.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org