kernel/linux.git/fs/f2fs, branch v6.12.96

f2fs: fix listxattr handling of corrupted xattr entries

2026-07-18T14:51:54+00:00

[ Upstream commit 5ef5bc304f23c3fe255d4936472378dcb74d0e94 ] Validate the xattr entry before reading its fields in f2fs_listxattr(). Return -EFSCORRUPTED when the entry is outside the valid xattr storage area instead of returning a successful partial result. Fixes: 688078e7f36c ("f2fs: fix to avoid memory leakage in f2fs_listxattr") Cc: stable@kernel.org Reviewed-by: Chao Yu Signed-off-by: Keshav Verma Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: fix potential deadlock in gc_merge path of f2fs_balance_fs()

2026-07-18T14:51:54+00:00

[ Upstream commit 8b4468ec023d0d1b4669dfb867588997cc03a06b ] When we mount device w/ gc_merge mount option, we may suffer below potential deadlock: Kworker GC trehad Truncator - f2fs_write_cache_pages - f2fs_write_single_data_page - f2fs_do_write_data_page - folio_start_writeback --- set writeback flag on folio - f2fs_outplace_write_data : cached folio in internal bio cache - f2fs_balance_fs - wake_up(gc_thread) : wake up gc thread to run foreground GC - finish_wait(fggc_wq) : wait on the waitqueue --- wait on GC thread to finish the work - truncate_inode_pages_range - __filemap_get_folio(, FGP_LOCK) --- lock folio - truncate_inode_partial_folio - folio_wait_writeback --- wait on writeback being cleared - do_garbage_collect - move_data_page - f2fs_get_lock_data_folio - lock on folio --- blocked on folio's lock In order to avoid such deadlock, let's call below functions to commit cached bios in GC_MERGE path of f2fs_balance_fs() as the same as we did in NOGC_MERGE path. - f2fs_submit_merged_write(sbi, DATA); - f2fs_submit_all_merged_ipu_writes(sbi); Cc: stable@kernel.org Fixes: 351df4b20115 ("f2fs: add segment operations") Cc: Ruipeng Qi Reported: Sandeep Dhavale Signed-off-by: Chao Yu Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: fix potential deadlock in f2fs_balance_fs()

2026-07-18T14:51:54+00:00

[ Upstream commit dd3114870771562036fdcf5abe813956f36d224d ] When the f2fs filesystem space is nearly exhausted, we encounter deadlock issues as below: INFO: task A:1890 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:A state:D stack:0 pid:1890 tgid:1626 ppid:1153 flags:0x00000204 Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 schedule+0x3c/0x118 io_schedule+0x44/0x68 folio_wait_bit_common+0x174/0x370 folio_wait_bit+0x20/0x38 folio_wait_writeback+0x54/0xc8 truncate_inode_partial_folio+0x70/0x1e0 truncate_inode_pages_range+0x1b0/0x450 truncate_pagecache+0x54/0x88 f2fs_file_write_iter+0x3e8/0xb80 do_iter_readv_writev+0xf0/0x1e0 vfs_writev+0x138/0x2c8 do_writev+0x88/0x130 __arm64_sys_writev+0x28/0x40 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x30/0xf8 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x190/0x198 INFO: task kworker/u8:11:2680853 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:11 state:D stack:0 pid:2680853 tgid:2680853 ppid:2 flags:0x00000208 Workqueue: writeback wb_workfn (flush-254:0) Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 schedule+0x3c/0x118 io_schedule+0x44/0x68 folio_wait_bit_common+0x174/0x370 __filemap_get_folio+0x214/0x348 pagecache_get_page+0x20/0x70 f2fs_get_read_data_page+0x150/0x3e8 f2fs_get_lock_data_page+0x2c/0x160 move_data_page+0x50/0x478 do_garbage_collect+0xd38/0x1528 f2fs_gc+0x240/0x7e0 f2fs_balance_fs+0x1a0/0x208 f2fs_write_single_data_page+0x6e4/0x730 f2fs_write_cache_pages+0x378/0x9b0 f2fs_write_data_pages+0x2e4/0x388 do_writepages+0x8c/0x2c8 __writeback_single_inode+0x4c/0x498 writeback_sb_inodes+0x234/0x4a8 __writeback_inodes_wb+0x58/0x118 wb_writeback+0x2f8/0x3c0 wb_workfn+0x2c4/0x508 process_one_work+0x180/0x408 worker_thread+0x258/0x368 kthread+0x118/0x128 ret_from_fork+0x10/0x200 INFO: task kworker/u8:8:2641297 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:8 state:D stack:0 pid:2641297 tgid:2641297 ppid:2 flags:0x00000208 Workqueue: writeback wb_workfn (flush-254:0) Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 rt_mutex_schedule+0x30/0x60 __rt_mutex_slowlock_locked.constprop.0+0x460/0x8a8 rwbase_write_lock+0x24c/0x378 down_write+0x1c/0x30 f2fs_balance_fs+0x184/0x208 f2fs_write_inode+0xf4/0x328 __writeback_single_inode+0x370/0x498 writeback_sb_inodes+0x234/0x4a8 __writeback_inodes_wb+0x58/0x118 wb_writeback+0x2f8/0x3c0 wb_workfn+0x2c4/0x508 process_one_work+0x180/0x408 worker_thread+0x258/0x368 kthread+0x118/0x128 ret_from_fork+0x10/0x20 INFO: task B:1902 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:B state:D stack:0 pid:1902 tgid:1626 ppid:1153 flags:0x0000020c Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 rt_mutex_schedule+0x30/0x60 __rt_mutex_slowlock_locked.constprop.0+0x460/0x8a8 rwbase_write_lock+0x24c/0x378 down_write+0x1c/0x30 f2fs_balance_fs+0x184/0x208 f2fs_map_blocks+0x94c/0x1110 f2fs_file_write_iter+0x228/0xb80 do_iter_readv_writev+0xf0/0x1e0 vfs_writev+0x138/0x2c8 do_writev+0x88/0x130 __arm64_sys_writev+0x28/0x40 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x30/0xf8 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x190/0x198 INFO: task sync:2769849 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:sync state:D stack:0 pid:2769849 tgid:2769849 ppid:736 flags:0x0000020c Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 schedule+0x3c/0x118 wb_wait_for_completion+0xb0/0xe8 sync_inodes_sb+0xc8/0x2b0 sync_inodes_one_sb+0x24/0x38 iterate_supers+0xa8/0x138 ksys_sync+0x54/0xc8 __arm64_sys_sync+0x18/0x30 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x30/0xf8 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x190/0x198 The root cause is a potential deadlock between the following tasks: kworker/u8:11 Thread A - f2fs_write_single_data_page - f2fs_do_write_data_page - folio_start_writeback(X) - f2fs_outplace_write_data - bio_add_folio(X) - folio_unlock(X) - truncate_inode_pages_range - __filemap_get_folio(X, FGP_LOCK) - truncate_inode_partial_folio(X) - folio_wait_writeback(X) - f2fs_balance_fs - f2fs_gc - do_garbage_collect - move_data_page - f2fs_get_lock_data_page - __filemap_get_folio(X, FGP_LOCK) Both threads try to access folio X. Thread A holds the lock but waits for writeback, while kworker waits for the lock. This causes a deadlock. Other threads also enter D state, waiting for locks such as gc_lock and writepages. OPU/IPU DATA folio are all affected by this issue. To avoid such potential deadlocks, always commit these cached folios before triggering f2fs_gc() in f2fs_balance_fs(). Suggested-by: Chao Yu Reviewed-by: Chao Yu Signed-off-by: Ruipeng Qi Signed-off-by: Jaegeuk Kim Stable-dep-of: 8b4468ec023d ("f2fs: fix potential deadlock in gc_merge path of f2fs_balance_fs()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: bound i_inline_xattr_size for non-inline-xattr inodes

2026-07-18T14:51:54+00:00

[ Upstream commit 378acf3cf19b6af6cba55e8dd1154c4e1504bae8 ] When the flexible_inline_xattr feature is enabled, do_read_inode() loads the on-disk i_inline_xattr_size unconditionally: if (f2fs_sb_has_flexible_inline_xattr(sbi)) fi->i_inline_xattr_size = le16_to_cpu(ri->i_inline_xattr_size); but sanity_check_inode() only range-checks it when the inode also has the FI_INLINE_XATTR flag set. An inode that carries an inline dentry or inline data but not FI_INLINE_XATTR -- the normal layout for an inline directory -- therefore keeps a fully attacker-controlled i_inline_xattr_size from a crafted image. get_inline_xattr_addrs() returns that value with no flag gating, so it feeds the inode geometry: MAX_INLINE_DATA() = 4 * (CUR_ADDRS_PER_INODE - i_inline_xattr_size - 1) NR_INLINE_DENTRY() = MAX_INLINE_DATA() * BITS_PER_BYTE / (...) addrs_per_page() = CUR_ADDRS_PER_INODE - i_inline_xattr_size A large i_inline_xattr_size drives MAX_INLINE_DATA() and NR_INLINE_DENTRY() negative, so make_dentry_ptr_inline() sets d->max (int) to a negative value. The inline directory walk then compares an unsigned long bit_pos against that negative d->max, which is promoted to a huge unsigned bound, and reads far past the inline area: while (bit_pos < d->max) /* fs/f2fs/dir.c */ ... test_bit_le(bit_pos, d->bitmap) / d->dentry[bit_pos] ... Mounting a crafted image and reading such a directory triggers an out-of-bounds read in f2fs_fill_dentries(); the same underflow also corrupts ADDRS_PER_INODE for regular files. Validate i_inline_xattr_size against MAX_INLINE_XATTR_SIZE whenever the flexible_inline_xattr feature is enabled -- i.e. whenever the value is loaded from disk and consumed -- and keep the lower MIN_INLINE_XATTR_SIZE bound gated on inodes that actually carry an inline xattr, so legitimate inodes with i_inline_xattr_size == 0 are still accepted. Cc: stable@vger.kernel.org Fixes: 6afc662e68b5 ("f2fs: support flexible inline xattr size") Signed-off-by: Bryam Vargas Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: atomic: fix UAF issue on f2fs_inode_info.atomic_inode

2026-07-18T14:51:54+00:00

[ Upstream commit e0288584baa5dc41df4a829a023c4c1b33fe53d7 ] - ioctl(F2FS_IOC_GARBAGE_COLLECT_RANGE) - shrink - f2fs_gc - gc_data_segment - ra_data_block(cow_inode) - mapping = F2FS_I(inode)->atomic_inode->i_mapping : f2fs_is_cow_file(cow_inode) is true - f2fs_evict_inode(atomic_inode) - clear_inode_flag(fi->cow_inode, FI_COW_FILE) - F2FS_I(fi->cow_inode)->atomic_inode = NULL ... - truncate_inode_pages_final(atomic_inode) - f2fs_grab_cache_folio(mapping) : create folio in atomic_inode->mapping - clear_inode(atomic_inode) - BUG_ON(atomic_inode->i_data.nrpages) We need to add a reference on fi->atomic_inode before using its mapping field during garbage collection, otherwise, it will cause UAF issue. Cc: stable@kernel.org Cc: Daeho Jeong Cc: Sunmin Jeong Fixes: 3db1de0e582c ("f2fs: change the current atomic write way") Fixes: f18d00769336 ("f2fs: use meta inode for GC of COW file") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: validate orphan inode entry count

2026-07-18T14:51:54+00:00

[ Upstream commit 846c499a65816d13f1186e3090e825e8bb8bcb8b ] f2fs_recover_orphan_inodes() trusts the orphan block entry_count when replaying orphan inodes from the checkpoint pack. A corrupted entry_count larger than F2FS_ORPHANS_PER_BLOCK makes the recovery loop read past the ino[] array and interpret footer or following data as inode numbers. On a crafted image, mounting an unpatched kernel can drive orphan recovery into f2fs_bug_on() and panic the kernel. Validate entry_count before consuming entries so corrupted checkpoint data fails the mount with -EFSCORRUPTED and requests fsck instead. Set ERROR_INCONSISTENT_ORPHAN as well, so the corruption reason can be recorded in the superblock s_errors[] field. This gives fsck a persistent hint even though mount-time orphan recovery failure may leave no chance to persist SBI_NEED_FSCK through a checkpoint. Cc: stable@kernel.org Fixes: 127e670abfa7 ("f2fs: add checkpoint operations") Signed-off-by: Wenjie Qi Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: keep atomic write retry from zeroing original data

2026-07-04T11:43:33+00:00

commit 6d874b65aadce56ac78f76129dbcfc2599b638f8 upstream. A partial atomic write reserves a block in the COW inode before reading the original data page for the untouched bytes in that page. If that read fails, write_begin returns an error but leaves the COW inode entry as NEW_ADDR. A retry of the same partial write then finds the COW entry, treats it as existing COW data, and f2fs_write_begin() zeroes the whole folio because blkaddr is NEW_ADDR. If the retry is committed, the bytes outside the retried write range are committed as zeroes instead of preserving the original file contents. Only use the COW inode as the read source when it already has a real data block. If the COW entry is still NEW_ADDR, treat it as a reservation to reuse: keep reading the old data from the original inode and avoid reserving or accounting the same atomic block again. Cc: stable@kernel.org Fixes: 3db1de0e582c ("f2fs: change the current atomic write way") Signed-off-by: Wenjie Qi Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node()

2026-07-04T11:43:33+00:00

commit 1f70ddb28a3c71df124da5fa4040c808116d6bb9 upstream. When __destroy_extent_node() sets the inode flag FI_NO_EXTENT, it does not reset the length of the largest extent to 0 and update the inode folio. Since modifications to the extent tree are disallowed afterward, the cached largest extent may become stale. This can trigger the following error in xfstests generic/388: F2FS-fs (dm-0): sanity_check_extent_cache: inode (ino=1761) extent info [220057, 57, 6] is incorrect, run fsck to fix In the f2fs_drop_inode path, __destroy_extent_node() does not need to guarantee that et->node_cnt is 0, because concurrency with writeback is expected in this path, and writeback may update the extent cache. This patch reverts commit ed78aeebef05 ("f2fs: fix node_cnt race between extent node destroy and writeback"), and remove the unnecessary zero check of et->node_cnt. Fixes: ed78aeebef05 ("f2fs: fix node_cnt race between extent node destroy and writeback") Cc: stable@vger.kernel.org Reported-by: Chao Yu Suggested-by: Chao Yu Signed-off-by: Yongpeng Yang Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

f2fs: validate ACL entry sizes in f2fs_acl_from_disk()

2026-07-04T11:43:33+00:00

commit c4810ada31e80cbe4011467c4f3b1e93f94134f3 upstream. f2fs_acl_count() only validates the aggregate ACL xattr length. A malformed ACL can still place ACL_USER or ACL_GROUP in a slot that only contains struct f2fs_acl_entry_short bytes, and f2fs_acl_from_disk() then reads entry->e_id before verifying that a full entry fits. Require a short entry before reading e_tag and e_perm, and require a full entry before reading e_id for ACL_USER and ACL_GROUP. Return -EFSCORRUPTED from these new truncated-entry checks, while keeping the pre-existing -EINVAL paths unchanged. Validation reproduced this kernel report: KASAN slab-out-of-bounds in __f2fs_get_acl+0x6fb/0x7e0 RIP: 0033:0x7f4b835ea7aa The buggy address belongs to the object at ffff888114589960 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 0 bytes to the right of allocated 8-byte region [ffff888114589960, ffff888114589968) Read of size 4 Call trace: dump_stack_lvl+0x66/0xa0 (?:?) print_report+0xce/0x630 (?:?) __f2fs_get_acl+0x6fb/0x7e0 (fs/f2fs/acl.c:169) srso_alias_return_thunk+0x5/0xfbef5 (?:?) __virt_addr_valid+0x224/0x430 (?:?) kasan_report+0xe0/0x110 (?:?) __f2fs_get_acl+0x5/0x7e0 (fs/f2fs/acl.c:169) __get_acl+0x281/0x380 (?:?) vfs_get_acl+0x10b/0x190 (?:?) do_get_acl+0x2a/0x410 (?:?) do_get_acl+0x9/0x410 (?:?) do_getxattr+0xe8/0x260 (?:?) filename_getxattr+0xd1/0x140 (?:?) do_getname+0x2d/0x2d0 (?:?) path_getxattrat+0x16c/0x200 (?:?) lock_release+0xc8/0x290 (?:?) cgroup_update_frozen+0x9d/0x320 (?:?) lockdep_hardirqs_on_prepare+0xea/0x1a0 (?:?) trace_hardirqs_on+0x1a/0x170 (?:?) _raw_spin_unlock_irq+0x28/0x50 (?:?) do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87) entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?) Cc: stable@kernel.org Fixes: af48b85b8cd3 ("f2fs: add xattr and acl functionalities") Assisted-by: Codex:gpt-5.5 Signed-off-by: Zhang Cen Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

f2fs: fix to round down start offset of fallocate for pin file

2026-07-04T11:43:33+00:00

commit 4275b59673eb60b02eec3997816c83f1f4b909c4 upstream. Currently, the length of fallocate for pin file is section-aligned to keep allocated sections from being selected as victims of GC. However, for the case that the start offset of fallocate is not aligned in section, the allocated sections can't be fully utilized. It's because a new section is allocated by f2fs_allocate_pinning_section() after using blks_per_sec blocks regardless of the start offset. As a result, several unexpected dirty segments may be created, including blocks assigned to the pinned file. To address this issue, let's round down the start offset of fallocate to the length of section. The reproducing scenario is as below chunk=$(((2<<20)+4096)) # 2MB + 4KB touch test f2fs_io pinfile set test f2fs_io fallocate 0 0 $chunk test f2fs_io fallocate 0 $chunk $chunk test f2fs_io fallocate 0 $((chunk*2)) $chunk test f2fs_io fiemap 0 $((chunk*3)) test Fiemap: offset = 0 len = 12288 logical addr. physical addr. length flags 0 0000000000000000 000000068c600000 0000000000400000 00001088 1 0000000000400000 000000003d400000 0000000000001000 00001088 2 0000000000401000 00000003eb200000 0000000000200000 00001088 3 0000000000601000 00000005e4200000 0000000000001000 00001088 4 0000000000602000 0000000605400000 0000000000200000 00001089 Cc: stable@vger.kernel.org Fixes: f5a53edcf01e ("f2fs: support aligned pinned file") Reviewed-by: Yunji Kang Reviewed-by: Yeongjin Gil Reviewed-by: Sungjong Seo Signed-off-by: Sunmin Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman