CVE-2025-38244

/// Technical description

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

smb: client: fix potential deadlock when reconnecting channels

Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order

and prevent the following deadlock from happening

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

WARNING: possible circular locking dependency detected

6.16.0-rc3-build2+ #1301 Tainted: G S W

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cifsd/6055 is trying to acquire lock:

ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200

but task is already holding lock:

ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&ret_buf->chan_lock){+.+.}-{3:3}:

validate_chain+0x1cf/0x270

__lock_acquire+0x60e/0x780

lock_acquire.part.0+0xb4/0x1f0

_raw_spin_lo

/// 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