mptcp: fix race condition in mptcp_schedule_work()
Summary
| CVE | CVE-2025-40258 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2025-12-04 16:16:19 UTC |
| Updated | 2026-06-02 14:16:32 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix race condition in mptcp_schedule_work()
syzbot reported use-after-free in mptcp_schedule_work() [1]
Issue here is that mptcp_schedule_work() schedules a work,
then gets a refcount on sk->sk_refcnt if the work was scheduled.
This refcount will be released by mptcp_worker().
[A] if (schedule_work(...)) {
[B] sock_hold(sk);
return true;
}
Problem is that mptcp_worker() can run immediately and complete before [B]
We need instead :
sock_hold(sk);
if (schedule_work(...))
return true;
sock_put(sk);
[1]
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25
Call Trace:
<TASK>
__refcount_add include/linux/refcount.h:-1 [inline]
__refcount_inc include/linux/refcount.h:366 [inline]
refcount_inc include/linux/refcount.h:383 [inline]
sock_hold include/net/sock.h:816 [inline]
mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943
mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x648/0x970 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x22f/0x710 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
run_ktimerd+0xcf/0x190 kernel/softirq.c:1138
smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f f865e6595acf33083168db76921e66ace8bf0e5b git |
Not specified |
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f 99908e2d601236842d705d5fd04fb349577316f5 git |
Not specified |
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f db4f7968a75250ca6c4ed70d0a78beabb2dcee18 git |
Not specified |
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f 8f9ba1a99a89feef9b5867c15a0141a97e893309 git |
Not specified |
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f ac28dfddedf6f209190950fc71bcff65ec4ab47b git |
Not specified |
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f 3fc7723ed01d1130d4bf7063c50e0af60ecccbb4 git |
Not specified |
| CNA |
Linux |
Linux |
affected 3b1d6210a9577369103330b0d802b0bf74b65e7f 035bca3f017ee9dea3a5a756e77a6f7138cc6eea git |
Not specified |
| CNA |
Linux |
Linux |
affected 5.7 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.7 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.10.247 5.10.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.15.197 5.15.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.1.159 6.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.6.118 6.6.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.60 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.17.10 6.17.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18 * original_commit_for_fix |
Not specified |
| ADP |
Siemens |
RUGGEDCOM RST2428P |
affected V4.0 custom |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/8f9ba1a99a89feef9b5867c15a0141a97e893309 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/99908e2d601236842d705d5fd04fb349577316f5 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/035bca3f017ee9dea3a5a756e77a6f7138cc6eea |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/f865e6595acf33083168db76921e66ace8bf0e5b |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/ac28dfddedf6f209190950fc71bcff65ec4ab47b |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/3fc7723ed01d1130d4bf7063c50e0af60ecccbb4 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| cert-portal.siemens.com/productcert/html/ssa-253495.html |
0b142b55-0307-4c5a-b3c9-f314f3fb7c5e |
cert-portal.siemens.com |
|
| git.kernel.org/stable/c/db4f7968a75250ca6c4ed70d0a78beabb2dcee18 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.