{"id":"DEBIAN-CVE-2025-22123","details":"In the Linux kernel, the following vulnerability has been resolved:  f2fs: fix to avoid accessing uninitialized curseg  syzbot reports a f2fs bug as below:  F2FS-fs (loop3): Stopped filesystem due to reason: 7 kworker/u8:7: attempt to access beyond end of device BUG: unable to handle page fault for address: ffffed1604ea3dfa RIP: 0010:get_ckpt_valid_blocks fs/f2fs/segment.h:361 [inline] RIP: 0010:has_curseg_enough_space fs/f2fs/segment.h:570 [inline] RIP: 0010:__get_secs_required fs/f2fs/segment.h:620 [inline] RIP: 0010:has_not_enough_free_secs fs/f2fs/segment.h:633 [inline] RIP: 0010:has_enough_free_secs+0x575/0x1660 fs/f2fs/segment.h:649  \u003cTASK\u003e  f2fs_is_checkpoint_ready fs/f2fs/segment.h:671 [inline]  f2fs_write_inode+0x425/0x540 fs/f2fs/inode.c:791  write_inode fs/fs-writeback.c:1525 [inline]  __writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745  writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976  wb_writeback+0x413/0xb80 fs/fs-writeback.c:2156  wb_do_writeback fs/fs-writeback.c:2303 [inline]  wb_workfn+0x410/0x1080 fs/fs-writeback.c:2343  process_one_work kernel/workqueue.c:3236 [inline]  process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317  worker_thread+0x870/0xd30 kernel/workqueue.c:3398  kthread+0x7a9/0x920 kernel/kthread.c:464  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244  Commit 8b10d3653735 (\"f2fs: introduce FAULT_NO_SEGMENT\") allows to trigger no free segment fault in allocator, then it will update curseg-\u003esegno to NULL_SEGNO, though, CP_ERROR_FLAG has been set, f2fs_write_inode() missed to check the flag, and access invalid curseg-\u003esegno directly in below call path, then resulting in panic:  - f2fs_write_inode  - f2fs_is_checkpoint_ready   - has_enough_free_secs    - has_not_enough_free_secs     - __get_secs_required      - has_curseg_enough_space       - get_ckpt_valid_blocks       : access invalid curseg-\u003esegno  To avoid this issue, let's: - check CP_ERROR_FLAG flag in prior to f2fs_is_checkpoint_ready() in f2fs_write_inode(). - in has_curseg_enough_space(), save curseg-\u003esegno into a temp variable, and verify its validation before use.","modified":"2026-08-27T23:05:12.761398018Z","published":"2025-04-16T15:16:06.450Z","upstream":["CVE-2025-22123"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-22123"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.33-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-22123.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.33-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-22123.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}