CVE-2024-42297

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> f2fs: fix to don&amp;#39;t dirty inode for readonly filesystem<br /> <br /> syzbot reports f2fs bug as below:<br /> <br /> kernel BUG at fs/f2fs/inode.c:933!<br /> RIP: 0010:f2fs_evict_inode+0x1576/0x1590 fs/f2fs/inode.c:933<br /> Call Trace:<br /> evict+0x2a4/0x620 fs/inode.c:664<br /> dispose_list fs/inode.c:697 [inline]<br /> evict_inodes+0x5f8/0x690 fs/inode.c:747<br /> generic_shutdown_super+0x9d/0x2c0 fs/super.c:675<br /> kill_block_super+0x44/0x90 fs/super.c:1667<br /> kill_f2fs_super+0x303/0x3b0 fs/f2fs/super.c:4894<br /> deactivate_locked_super+0xc1/0x130 fs/super.c:484<br /> cleanup_mnt+0x426/0x4c0 fs/namespace.c:1256<br /> task_work_run+0x24a/0x300 kernel/task_work.c:180<br /> ptrace_notify+0x2cd/0x380 kernel/signal.c:2399<br /> ptrace_report_syscall include/linux/ptrace.h:411 [inline]<br /> ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]<br /> syscall_exit_work kernel/entry/common.c:251 [inline]<br /> syscall_exit_to_user_mode_prepare kernel/entry/common.c:278 [inline]<br /> __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]<br /> syscall_exit_to_user_mode+0x15c/0x280 kernel/entry/common.c:296<br /> do_syscall_64+0x50/0x110 arch/x86/entry/common.c:88<br /> entry_SYSCALL_64_after_hwframe+0x63/0x6b<br /> <br /> The root cause is:<br /> - do_sys_open<br /> - f2fs_lookup<br /> - __f2fs_find_entry<br /> - f2fs_i_depth_write<br /> - f2fs_mark_inode_dirty_sync<br /> - f2fs_dirty_inode<br /> - set_inode_flag(inode, FI_DIRTY_INODE)<br /> <br /> - umount<br /> - kill_f2fs_super<br /> - kill_block_super<br /> - generic_shutdown_super<br /> - sync_filesystem<br /> : sb is readonly, skip sync_filesystem()<br /> - evict_inodes<br /> - iput<br /> - f2fs_evict_inode<br /> - f2fs_bug_on(sbi, is_inode_flag_set(inode, FI_DIRTY_INODE))<br /> : trigger kernel panic<br /> <br /> When we try to repair i_current_depth in readonly filesystem, let&amp;#39;s<br /> skip dirty inode to avoid panic in later f2fs_evict_inode().