kernel/linux.git/fs/f2fs/sysfs.c, branch v6.1.168

f2fs: fix out-of-bounds access in sysfs attribute read/write

2026-02-19T15:25:21+00:00

[ Upstream commit 98ea0039dbfdd00e5cc1b9a8afa40434476c0955 ] Some f2fs sysfs attributes suffer from out-of-bounds memory access and incorrect handling of integer values whose size is not 4 bytes. For example: vm:~# echo 65537 > /sys/fs/f2fs/vde/carve_out vm:~# cat /sys/fs/f2fs/vde/carve_out 65537 vm:~# echo 4294967297 > /sys/fs/f2fs/vde/atgc_age_threshold vm:~# cat /sys/fs/f2fs/vde/atgc_age_threshold 1 carve_out maps to {struct f2fs_sb_info}->carve_out, which is a 8-bit integer. However, the sysfs interface allows setting it to a value larger than 255, resulting in an out-of-range update. atgc_age_threshold maps to {struct atgc_management}->age_threshold, which is a 64-bit integer, but its sysfs interface cannot correctly set values larger than UINT_MAX. The root causes are: 1. __sbi_store() treats all default values as unsigned int, which prevents updating integers larger than 4 bytes and causes out-of-bounds writes for integers smaller than 4 bytes. 2. f2fs_sbi_show() also assumes all default values are unsigned int, leading to out-of-bounds reads and incorrect access to integers larger than 4 bytes. This patch introduces {struct f2fs_attr}->size to record the actual size of the integer associated with each sysfs attribute. With this information, sysfs read and write operations can correctly access and update values according to their real data size, avoiding memory corruption and truncation. Fixes: b59d0bae6ca3 ("f2fs: add sysfs support for controlling the gc_thread") Cc: stable@kernel.org Signed-off-by: Jinbao Liu Signed-off-by: Yongpeng Yang Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim [ adapted F2FS_STAT_ATTR macro to include .size field and used sprintf instead of sysfs_emit in the replaced baseline code ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: check validation of fault attrs in f2fs_build_fault_attr()

2024-07-11T10:47:09+00:00

[ Upstream commit 4ed886b187f47447ad559619c48c086f432d2b77 ] - It missed to check validation of fault attrs in parse_options(), let's fix to add check condition in f2fs_build_fault_attr(). - Use f2fs_build_fault_attr() in __sbi_store() to clean up code. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: convert to use bitmap API

2024-01-10T16:10:30+00:00

[ Upstream commit 447286ebadaafa551550704ff0b42eb08b1d1cb2 ] Let's use BIT() and GENMASK() instead of open it. Signed-off-by: Yangtao Li Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: f5f3bd903a5d ("f2fs: set the default compress_level on ioctl") Signed-off-by: Sasha Levin

f2fs: fix iostat lock protection

2023-05-11T14:03:20+00:00

[ Upstream commit 144f1cd40bf91fb3ac1d41806470756ce774f389 ] Made iostat lock irq safe to avoid potentinal deadlock. Deadlock scenario: f2fs_attr_store -> f2fs_sbi_store -> _sbi_store -> spin_lock(sbi->iostat_lock) -> scsi_end_request -> bio_endio -> f2fs_dio_read_end_io -> f2fs_update_iostat -> spin_lock_irqsave(sbi->iostat_lock) ===> Dead lock here Fixes: 61803e984307 ("f2fs: fix iostat related lock protection") Fixes: a1e09b03e6f5 ("f2fs: use iomap for direct I/O") Signed-off-by: Qilin Tan Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: introduce cp_status sysfs entry

2022-10-04T20:31:44+00:00

This patch adds a new sysfs entry named cp_status, it can output checkpoint flags in real time. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: remove gc_urgent_high_limited for cleanup

2022-08-30T04:15:51+00:00

Remove redundant sbi->gc_urgent_high_limited. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: introduce sysfs atomic write statistics

2022-07-31T03:17:07+00:00

introduce the below 4 new sysfs node for atomic write statistics. - current_atomic_write: the total current atomic write block count, which is not committed yet. - peak_atomic_write: the peak value of total current atomic write block count after boot. - committed_atomic_block: the accumulated total committed atomic write block count after boot. - revoked_atomic_block: the accumulated total revoked atomic write block count after boot. Signed-off-by: Daeho Jeong Signed-off-by: Jaegeuk Kim

f2fs: add a sysfs entry to show zone capacity

2022-07-31T03:16:20+00:00

This patch adds a sysfs entry showing the unusable space in a section made by zone capacity. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

Merge tag 'f2fs-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2022-03-22T17:00:31+00:00

Pull f2fs updates from Jaegeuk Kim: "In this cycle, f2fs has some performance improvements for Android workloads such as using read-unfair rwsems and adding some sysfs entries to control GCs and discard commands in more details. In addtiion, it has some tunings to improve the recovery speed after sudden power-cut. Enhancement: - add reader-unfair rwsems with F2FS_UNFAIR_RWSEM: will replace with generic API support - adjust to make the readahead/recovery flow more efficiently - sysfs entries to control issue speeds of GCs and Discard commands - enable idmapped mounts Bug fix: - correct wrong error handling routines - fix missing conditions in quota - fix a potential deadlock between writeback and block plug routines - fix a deadlock btween freezefs and evict_inode We've added some boundary checks to avoid kernel panics on corrupted images, and several minor code clean-ups" * tag 'f2fs-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (27 commits) f2fs: fix to do sanity check on .cp_pack_total_block_count f2fs: make gc_urgent and gc_segment_mode sysfs node readable f2fs: use aggressive GC policy during f2fs_disable_checkpoint() f2fs: fix compressed file start atomic write may cause data corruption f2fs: initialize sbi->gc_mode explicitly f2fs: introduce gc_urgent_mid mode f2fs: compress: fix to print raw data size in error path of lz4 decompression f2fs: remove redundant parameter judgment f2fs: use spin_lock to avoid hang f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs f2fs: remove unnecessary read for F2FS_FITS_IN_INODE f2fs: introduce F2FS_UNFAIR_RWSEM to support unfair rwsem f2fs: avoid an infinite loop in f2fs_sync_dirty_inodes f2fs: fix to do sanity check on curseg->alloc_type f2fs: fix to avoid potential deadlock f2fs: quota: fix loop condition at f2fs_quota_sync() f2fs: Restore rwsem lockdep support f2fs: fix missing free nid in f2fs_handle_failed_inode f2fs: support idmapped mounts f2fs: add a way to limit roll forward recovery time ...

f2fs: make gc_urgent and gc_segment_mode sysfs node readable

2022-03-21T16:09:54+00:00

Changed a way of showing values of them to use strings. Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim