Linux Kernel up to 6.5.11/6.6.1 fs/f2fs/super.c f2fs_put_super infinite loop

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.5.11/6.6.1. It has been declared as critical. Affected is the function f2fs_put_super of the file fs/f2fs/super.c. The manipulation results in infinite loop. This vulnerability is reported as CVE-2023-52848. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.5.11/6.6.1. Affected is the function f2fs_put_super of the file fs/f2fs/super.c. The manipulation with an unknown input leads to a infinite loop vulnerability. CWE is classifying the issue as CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. This is going to have an impact on availability. CVE summarizes:

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.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2023-52848. The exploitability is told to be difficult. There are known technical details, but no exploit is available.

Upgrading to version 6.5.12 or 6.6.2 eliminates this vulnerability. Applying the patch eb42e1862aa7/10b2a6c0dade/a4639380bbe6 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.5.0
• 6.5.1
• 6.5.2
• 6.5.3
• 6.5.4
• 6.5.5
• 6.5.6
• 6.5.7
• 6.5.8
• 6.5.9
• 6.5.10
• 6.5.11
• 6.6.0
• 6.6.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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