In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to drop meta_inode's page cache in f2fs_put_super() syzbot reports a kernel bug as below: F2FS-fs (loop1): detect filesystem reference count leak during umount, type: 10, count: 1 kernel BUG at fs/f2fs/super.c:1639! CPU: 0 PID: 15451 Comm: syz-executor.1 Not tainted 6.5.0-syzkaller-09338-ge0152e7481c6 #0 RIP: 0010:f2fs_put_super+0xce1/0xed0 fs/f2fs/super.c:1639 Call Trace: generic_shutdown_super+0x161/0x3c0 fs/super.c:693 kill_block_super+0x3b/0x70 fs/super.c:1646 kill_f2fs_super+0x2b7/0x3d0 fs/f2fs/super.c:4879 deactivate_locked_super+0x9a/0x170 fs/super.c:481 deactivate_super+0xde/0x100 fs/super.c:514 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd In f2fs_put_super(), it tries to do sanity check on dirty and IO reference count of f2fs, once there is any reference count leak, it will trigger panic. The root case is, during f2fs_put_super(), if there is any IO error in f2fs_wait_on_all_pages(), we missed to truncate meta_inode's page cache later, result in panic, fix this case.
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
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Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
|
UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
None (N)
|
Aucune modification de données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |