CVE-2025-39932

Critical

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: let smbd_destroy() call disable_work_sync(&info->post_send_credits_work) In smbd_destroy() we may destroy the memory so we better wait until post_send_credits_work is no longer pending and will never be started again. I actually just hit the case using rxe: WARNING: CPU: 0 PID: 138 at drivers/infiniband/sw/rxe/rxe_verbs.c:1032 rxe_post_recv+0x1ee/0x480 [rdma_rxe] ... [ 5305.686979] [ T138] smbd_post_recv+0x445/0xc10 [cifs] [ 5305.687135] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687149] [ T138] ? __kasan_check_write+0x14/0x30 [ 5305.687185] [ T138] ? __pfx_smbd_post_recv+0x10/0x10 [cifs] [ 5305.687329] [ T138] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 5305.687356] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687368] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687378] [ T138] ? _raw_spin_unlock_irqrestore+0x11/0x60 [ 5305.687389] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687399] [ T138] ? get_receive_buffer+0x168/0x210 [cifs] [ 5305.687555] [ T138] smbd_post_send_credits+0x382/0x4b0 [cifs] [ 5305.687701] [ T138] ? __pfx_smbd_post_send_credits+0x10/0x10 [cifs] [ 5305.687855] [ T138] ? __pfx___schedule+0x10/0x10 [ 5305.687865] [ T138] ? __pfx__raw_spin_lock_irq+0x10/0x10 [ 5305.687875] [ T138] ? queue_delayed_work_on+0x8e/0xa0 [ 5305.687889] [ T138] process_one_work+0x629/0xf80 [ 5305.687908] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687917] [ T138] ? __kasan_check_write+0x14/0x30 [ 5305.687933] [ T138] worker_thread+0x87f/0x1570 ... It means rxe_post_recv was called after rdma_destroy_qp(). This happened because put_receive_buffer() was triggered by ib_drain_qp() and called: queue_work(info->workqueue, &info->post_send_credits_work);

SeverityCritical
CVSS9.8
Exploit probability—
ProductLinux Kernel
PublishedOct 4, 2025
First seenOct 4, 2025

How to fix

Update
  • linux linux_kernel6.12.49, 6.16.9 or later

Affected products

ProductAffected versionsFixed in
linux linux_kernel4.16 ≤ v < 6.12.49, 6.13 ≤ v < 6.16.9, 6.176.12.49, 6.16.9

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.