CVE-2024-56744

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix to avoid potential deadlock in f2fs_record_stop_reason()

syzbot reports deadlock issue of f2fs as below:

======================================================

WARNING: possible circular locking dependency detected

6.12.0-rc3-syzkaller-00087-gc964ced77262 #0 Not tainted

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kswapd0/79 is trying to acquire lock:

ffff888011824088 (&sbi->sb_lock){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2199 [inline]

ffff888011824088 (&sbi->sb_lock){++++}-{3:3}, at: f2fs_record_stop_reason+0x52/0x1d0 fs/f2fs/super.c:4068

but task is already holding lock:

ffff88804bd92610 (sb_internal#2){.+.+}-{0:0}, at: f2fs_evict_inode+0x662/0x15c0 fs/f2fs/inode.c:842

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (sb_internal#2){.+.+}-{0:0}:

lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825

percpu_down_rea

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References