In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to don't dirty inode for readonly filesystem syzbot reports f2fs bug as below: kernel BUG at fs/f2fs/inode.c:933! RIP: 0010:f2fs_evict_inode+0x1576/0x1590 fs/f2fs/inode.c:933 Call Trace: evict+0x2a4/0x620 fs/inode.c:664 dispose_list fs/inode.c:697 [inline] evict_inodes+0x5f8/0x690 fs/inode.c:747 generic_shutdown_super+0x9d/0x2c0 fs/super.c:675 kill_block_super+0x44/0x90 fs/super.c:1667 kill_f2fs_super+0x303/0x3b0 fs/f2fs/super.c:4894 deactivate_locked_super+0xc1/0x130 fs/super.c:484 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1256 task_work_run+0x24a/0x300 kernel/task_work.c:180 ptrace_notify+0x2cd/0x380 kernel/signal.c:2399 ptrace_report_syscall include/linux/ptrace.h:411 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline] syscall_exit_work kernel/entry/common.c:251 [inline] syscall_exit_to_user_mode_prepare kernel/entry/common.c:278 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x15c/0x280 kernel/entry/common.c:296 do_syscall_64+0x50/0x110 arch/x86/entry/common.c:88 entry_SYSCALL_64_after_hwframe+0x63/0x6b The root cause is: - do_sys_open - f2fs_lookup - __f2fs_find_entry - f2fs_i_depth_write - f2fs_mark_inode_dirty_sync - f2fs_dirty_inode - set_inode_flag(inode, FI_DIRTY_INODE) - umount - kill_f2fs_super - kill_block_super - generic_shutdown_super - sync_filesystem : sb is readonly, skip sync_filesystem() - evict_inodes - iput - f2fs_evict_inode - f2fs_bug_on(sbi, is_inode_flag_set(inode, FI_DIRTY_INODE)) : trigger kernel panic When we try to repair i_current_depth in readonly filesystem, let's skip dirty inode to avoid panic in later f2fs_evict_inode().
| Métrique | Valeur | Interprétation |
|---|---|---|
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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 |