kernel/linux.git/fs/f2fs/file.c, branch v6.6.131

f2fs: fix to avoid updating compression context during writeback

2026-01-11T14:22:27+00:00

[ Upstream commit 10b591e7fb7cdc8c1e53e9c000dc0ef7069aaa76 ] Bai, Shuangpeng reported a bug as below: Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 11441 Comm: syz.0.46 Not tainted 6.17.0 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:f2fs_all_cluster_page_ready+0x106/0x550 fs/f2fs/compress.c:857 Call Trace: f2fs_write_cache_pages fs/f2fs/data.c:3078 [inline] __f2fs_write_data_pages fs/f2fs/data.c:3290 [inline] f2fs_write_data_pages+0x1c19/0x3600 fs/f2fs/data.c:3317 do_writepages+0x38e/0x640 mm/page-writeback.c:2634 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] __filemap_fdatawrite_range mm/filemap.c:419 [inline] file_write_and_wait_range+0x2ba/0x3e0 mm/filemap.c:794 f2fs_do_sync_file+0x6e6/0x1b00 fs/f2fs/file.c:294 generic_write_sync include/linux/fs.h:3043 [inline] f2fs_file_write_iter+0x76e/0x2700 fs/f2fs/file.c:5259 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7e9/0xe00 fs/read_write.c:686 ksys_write+0x19d/0x2d0 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf7/0x470 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The bug was triggered w/ below race condition: fsync setattr ioctl - f2fs_do_sync_file - file_write_and_wait_range - f2fs_write_cache_pages : inode is non-compressed : cc.cluster_size = F2FS_I(inode)->i_cluster_size = 0 - tag_pages_for_writeback - f2fs_setattr - truncate_setsize - f2fs_truncate - f2fs_fileattr_set - f2fs_setflags_common - set_compress_context : F2FS_I(inode)->i_cluster_size = 4 : set_inode_flag(inode, FI_COMPRESSED_FILE) - f2fs_compressed_file : return true - f2fs_all_cluster_page_ready : "pgidx % cc->cluster_size" trigger dividing 0 issue Let's change as below to fix this issue: - introduce a new atomic type variable .writeback in structure f2fs_inode_info to track the number of threads which calling f2fs_write_cache_pages(). - use .i_sem lock to protect .writeback update. - check .writeback before update compression context in f2fs_setflags_common() to avoid race w/ ->writepages. Fixes: 4c8ff7095bef ("f2fs: support data compression") Cc: stable@kernel.org Reported-by: Bai, Shuangpeng Tested-by: Bai, Shuangpeng Closes: https://lore.kernel.org/lkml/44D8F7B3-68AD-425F-9915-65D27591F93F@psu.edu Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim [ Adjust context ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: drop inode from the donation list when the last file is closed

2026-01-11T14:22:27+00:00

[ Upstream commit 078cad8212ce4f4ebbafcc0936475b8215e1ca2a ] Let's drop the inode from the donation list when there is no other open file. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 10b591e7fb7c ("f2fs: fix to avoid updating compression context during writeback") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: keep POSIX_FADV_NOREUSE ranges

2026-01-11T14:22:27+00:00

[ Upstream commit ef0c333cad8d1940f132a7ce15f15920216a3bd5 ] This patch records POSIX_FADV_NOREUSE ranges for users to reclaim the caches instantly off from LRU. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 10b591e7fb7c ("f2fs: fix to avoid updating compression context during writeback") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: remove unused GC_FAILURE_PIN

2026-01-11T14:22:27+00:00

[ Upstream commit 968c4f72b23c0c8f1e94e942eab89b8c5a3022e7 ] After commit 3db1de0e582c ("f2fs: change the current atomic write way"), we removed all GC_FAILURE_ATOMIC usage, let's change i_gc_failures[] array to i_pin_failure for cleanup. Meanwhile, let's define i_current_depth and i_gc_failures as union variable due to they won't be valid at the same time. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 10b591e7fb7c ("f2fs: fix to avoid updating compression context during writeback") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: fix to avoid updating zero-sized extent in extent cache

2026-01-11T14:21:59+00:00

commit 7c37c79510329cd951a4dedf3f7bf7e2b18dccec upstream. As syzbot reported: F2FS-fs (loop0): __update_extent_tree_range: extent len is zero, type: 0, extent [0, 0, 0], age [0, 0] ------------[ cut here ]------------ kernel BUG at fs/f2fs/extent_cache.c:678! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:__update_extent_tree_range+0x13bc/0x1500 fs/f2fs/extent_cache.c:678 Call Trace: f2fs_update_read_extent_cache_range+0x192/0x3e0 fs/f2fs/extent_cache.c:1085 f2fs_do_zero_range fs/f2fs/file.c:1657 [inline] f2fs_zero_range+0x10c1/0x1580 fs/f2fs/file.c:1737 f2fs_fallocate+0x583/0x990 fs/f2fs/file.c:2030 vfs_fallocate+0x669/0x7e0 fs/open.c:342 ioctl_preallocate fs/ioctl.c:289 [inline] file_ioctl+0x611/0x780 fs/ioctl.c:-1 do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:576 __do_sys_ioctl fs/ioctl.c:595 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f07bc58eec9 In error path of f2fs_zero_range(), it may add a zero-sized extent into extent cache, it should be avoided. Fixes: 6e9619499f53 ("f2fs: support in batch fzero in dnode page") Cc: stable@kernel.org Reported-by: syzbot+24124df3170c3638b35f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-f2fs-devel/68e5d698.050a0220.256323.0032.GAE@google.com Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

f2fs: fix to mitigate overhead of f2fs_zero_post_eof_page()

2025-10-15T09:58:01+00:00

[ Upstream commit c2f7c32b254006ad48f8e4efb2e7e7bf71739f17 ] f2fs_zero_post_eof_page() may cuase more overhead due to invalidate_lock and page lookup, change as below to mitigate its overhead: - check new_size before grabbing invalidate_lock - lookup and invalidate pages only in range of [old_size, new_size] Fixes: ba8dac350faf ("f2fs: fix to zero post-eof page") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to truncate first page in error path of f2fs_truncate()

2025-10-15T09:58:01+00:00

[ Upstream commit 9251a9e6e871cb03c4714a18efa8f5d4a8818450 ] syzbot reports a bug as below: loop0: detected capacity change from 0 to 40427 F2FS-fs (loop0): Wrong SSA boundary, start(3584) end(4096) blocks(3072) F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop0): invalid crc value F2FS-fs (loop0): f2fs_convert_inline_folio: corrupted inline inode ino=3, i_addr[0]:0x1601, run fsck to fix. ------------[ cut here ]------------ kernel BUG at fs/inode.c:753! RIP: 0010:clear_inode+0x169/0x190 fs/inode.c:753 Call Trace: evict+0x504/0x9c0 fs/inode.c:810 f2fs_fill_super+0x5612/0x6fa0 fs/f2fs/super.c:5047 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692 vfs_get_tree+0x8f/0x2b0 fs/super.c:1815 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4324 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f During f2fs_evict_inode(), clear_inode() detects that we missed to truncate all page cache before destorying inode, that is because in below path, we will create page #0 in cache, but missed to drop it in error path, let's fix it. - evict - f2fs_evict_inode - f2fs_truncate - f2fs_convert_inline_inode - f2fs_grab_cache_folio : create page #0 in cache - f2fs_convert_inline_folio : sanity check failed, return -EFSCORRUPTED - clear_inode detects that inode->i_data.nrpages is not zero Fixes: 92dffd01790a ("f2fs: convert inline_data when i_size becomes large") Reported-by: syzbot+90266696fe5daacebd35@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-f2fs-devel/68c09802.050a0220.3c6139.000e.GAE@google.com Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: check the generic conditions first

2025-08-28T14:28:28+00:00

[ Upstream commit e23ab8028de0d92df5921a570f5212c0370db3b5 ] Let's return errors caught by the generic checks. This fixes generic/494 where it expects to see EBUSY by setattr_prepare instead of EINVAL by f2fs for active swapfile. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to avoid use-after-free issue in f2fs_filemap_fault

2025-07-10T14:03:21+00:00

commit eb70d5a6c932d9d23f4bb3e7b83782c21ac4b064 upstream. syzbot reports a f2fs bug as below: BUG: KASAN: slab-use-after-free in f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49 Read of size 8 at addr ffff88807bb22680 by task syz-executor184/5058 CPU: 0 PID: 5058 Comm: syz-executor184 Not tainted 6.7.0-syzkaller-09928-g052d534373b7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x163/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x170 mm/kasan/report.c:601 f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49 __do_fault+0x131/0x450 mm/memory.c:4376 do_shared_fault mm/memory.c:4798 [inline] do_fault mm/memory.c:4872 [inline] do_pte_missing mm/memory.c:3745 [inline] handle_pte_fault mm/memory.c:5144 [inline] __handle_mm_fault+0x23b7/0x72b0 mm/memory.c:5285 handle_mm_fault+0x27e/0x770 mm/memory.c:5450 do_user_addr_fault arch/x86/mm/fault.c:1364 [inline] handle_page_fault arch/x86/mm/fault.c:1507 [inline] exc_page_fault+0x456/0x870 arch/x86/mm/fault.c:1563 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 The root cause is: in f2fs_filemap_fault(), vmf->vma may be not alive after filemap_fault(), so it may cause use-after-free issue when accessing vmf->vma->vm_flags in trace_f2fs_filemap_fault(). So it needs to keep vm_flags in separated temporary variable for tracepoint use. Fixes: 87f3afd366f7 ("f2fs: add tracepoint for f2fs_vm_page_mkwrite()") Reported-and-tested-by: syzbot+763afad57075d3f862f2@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/000000000000e8222b060f00db3b@google.com Cc: Ed Tsai Suggested-by: Hillf Danton Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

f2fs: fix to zero post-eof page

2025-07-10T14:03:14+00:00

[ Upstream commit ba8dac350faf16afc129ce6303ca4feaf083ccb1 ] fstest reports a f2fs bug: #generic/363 42s ... [failed, exit status 1]- output mismatch (see /share/git/fstests/results//generic/363.out.bad) # --- tests/generic/363.out 2025-01-12 21:57:40.271440542 +0800 # +++ /share/git/fstests/results//generic/363.out.bad 2025-05-19 19:55:58.000000000 +0800 # @@ -1,2 +1,78 @@ # QA output created by 363 # fsx -q -S 0 -e 1 -N 100000 # +READ BAD DATA: offset = 0xd6fb, size = 0xf044, fname = /mnt/f2fs/junk # +OFFSET GOOD BAD RANGE # +0x1540d 0x0000 0x2a25 0x0 # +operation# (mod 256) for the bad data may be 37 # +0x1540e 0x0000 0x2527 0x1 # ... # (Run 'diff -u /share/git/fstests/tests/generic/363.out /share/git/fstests/results//generic/363.out.bad' to see the entire diff) Ran: generic/363 Failures: generic/363 Failed 1 of 1 tests The root cause is user can update post-eof page via mmap [1], however, f2fs missed to zero post-eof page in below operations, so, once it expands i_size, then it will include dummy data locates previous post-eof page, so during below operations, we need to zero post-eof page. Operations which can include dummy data after previous i_size after expanding i_size: - write - mapwrite [1] - truncate - fallocate * preallocate * zero_range * insert_range * collapse_range - clone_range (doesn’t support in f2fs) - copy_range (doesn’t support in f2fs) [1] https://man7.org/linux/man-pages/man2/mmap.2.html 'BUG section' Cc: stable@kernel.org Signed-off-by: Chao Yu Reviewed-by: Zhiguo Niu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin