Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2024-56640— net/smc: fix LGR and link use-after-free issue

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于net/smc模块中LGR和链接的释放后重用问题。

CVSS 9.8 · Critical EPSS 0.62% · P49

Possible ATT&CK Techniques 1 AI

T1211 · Exploitation for Stealth

Affected Version Matrix 12

VendorProduct Version RangeStatus
Linux Linux 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8< f502a88fdd415647a1f2dc45fac71b9c522a052b affected
3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8< 0cf598548a6c36d90681d53c6b77d52363f2f295 affected
3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8< 673d606683ac70bc074ca6676b938bff18635226 affected
3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8< 6f0ae06a234a78ae137064f2c89135ac078a00eb affected
3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8< 2c7f14ed9c19ec0f149479d1c2842ec1f9bf76d7 affected
4.18 affected
< 4.18 unaffected
5.15.174≤ 5.15.* unaffected
… +4 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2024-56640

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
net/smc: fix LGR and link use-after-free issue
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix LGR and link use-after-free issue We encountered a LGR/link use-after-free issue, which manifested as the LGR/link refcnt reaching 0 early and entering the clear process, making resource access unsafe. refcount_t: addition on 0; use-after-free. WARNING: CPU: 14 PID: 107447 at lib/refcount.c:25 refcount_warn_saturate+0x9c/0x140 Workqueue: events smc_lgr_terminate_work [smc] Call trace: refcount_warn_saturate+0x9c/0x140 __smc_lgr_terminate.part.45+0x2a8/0x370 [smc] smc_lgr_terminate_work+0x28/0x30 [smc] process_one_work+0x1b8/0x420 worker_thread+0x158/0x510 kthread+0x114/0x118 or refcount_t: underflow; use-after-free. WARNING: CPU: 6 PID: 93140 at lib/refcount.c:28 refcount_warn_saturate+0xf0/0x140 Workqueue: smc_hs_wq smc_listen_work [smc] Call trace: refcount_warn_saturate+0xf0/0x140 smcr_link_put+0x1cc/0x1d8 [smc] smc_conn_free+0x110/0x1b0 [smc] smc_conn_abort+0x50/0x60 [smc] smc_listen_find_device+0x75c/0x790 [smc] smc_listen_work+0x368/0x8a0 [smc] process_one_work+0x1b8/0x420 worker_thread+0x158/0x510 kthread+0x114/0x118 It is caused by repeated release of LGR/link refcnt. One suspect is that smc_conn_free() is called repeatedly because some smc_conn_free() from server listening path are not protected by sock lock. e.g. Calls under socklock | smc_listen_work ------------------------------------------------------- lock_sock(sk) | smc_conn_abort smc_conn_free | \- smc_conn_free \- smcr_link_put | \- smcr_link_put (duplicated) release_sock(sk) So here add sock lock protection in smc_listen_work() path, making it exclusive with other connection operations.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于net/smc模块中LGR和链接的释放后重用问题。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8 ~ f502a88fdd415647a1f2dc45fac71b9c522a052b -
Linux Linux 4.18 -

II. Public POCs for CVE-2024-56640

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2024-56640

请登录查看更多情报信息。

Patches & Fixes for CVE-2024-56640 (5)

Same Patch Batch · Linux · 2024-12-27 · 221 CVEs total

CVE-2024-53209 9.8 CRITICAL bnxt_en: Fix receive ring space parameters when XDP is active
CVE-2024-53206 9.8 CRITICAL tcp: Fix use-after-free of nreq in reqsk_timer_handler().
CVE-2024-56656 9.8 CRITICAL bnxt_en: Fix aggregation ID mask to prevent oops on 5760X chips
CVE-2024-53169 9.8 CRITICAL nvme-fabrics: fix kernel crash while shutting down controller
CVE-2024-56645 9.8 CRITICAL can: j1939: j1939_session_new(): fix skb reference counting
CVE-2024-53186 9.8 CRITICAL ksmbd: fix use-after-free in SMB request handling
CVE-2024-53176 9.8 CRITICAL smb: During unmount, ensure all cached dir instances drop their dentry
CVE-2024-53177 9.8 CRITICAL smb: prevent use-after-free due to open_cached_dir error paths
CVE-2024-53179 9.8 CRITICAL smb: client: fix use-after-free of signing key
CVE-2024-56591 8.8 HIGH Bluetooth: hci_conn: Use disable_delayed_work_sync
CVE-2024-56653 8.8 HIGH Bluetooth: btmtk: avoid UAF in btmtk_process_coredump
CVE-2024-56651 8.8 HIGH can: hi311x: hi3110_can_ist(): fix potential use-after-free
CVE-2024-53224 8.8 HIGH RDMA/mlx5: Move events notifier registration to be after device registration
CVE-2024-53237 8.8 HIGH Bluetooth: fix use-after-free in device_for_each_child()
CVE-2024-56669 8.8 HIGH iommu/vt-d: Remove cache tags before disabling ATS
CVE-2024-56626 8.8 HIGH ksmbd: fix Out-of-Bounds Write in ksmbd_vfs_stream_write
CVE-2024-56627 8.1 HIGH ksmbd: fix Out-of-Bounds Read in ksmbd_vfs_stream_read
CVE-2024-53220 7.8 HIGH f2fs: fix to account dirty data in __get_secs_required()
CVE-2024-56576 7.8 HIGH media: i2c: tc358743: Fix crash in the probe error path when using polling
CVE-2024-56604 7.8 HIGH Bluetooth: RFCOMM: avoid leaving dangling sk pointer in rfcomm_sock_alloc()

Showing top 20 of 221 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2024-56640

No comments yet

Leave a comment