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TI-2024-23793 Aliases CVE-2024-35934GHSA-xvf2-5mhq-w7h6

net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list()

Priority LOW 24Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 5 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list() Many syzbot reports show extreme rtnl pressure, and many of them hint that smc acquires rtnl in netns creation for no good reason [1] This patch returns early from smc_pnet_net_init() if there is no netdevice yet. I am not even sure why smc_pnet_create_pnetids_list() even exists, because smc_pnet_netdev_event() is also calling smc_pnet_add_base_pnetid() when handling NETDEV_UP event. [1] extract of typical syzbot reports 2 locks held by syz-executor.3/12252: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.4/12253: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.1/12257: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.2/12261: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.0/12265: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.3/12268: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.4/12271: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.1/12274: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878 2 locks held by syz-executor.2/12280: #0: ffffffff8f369610 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:809 [inline] #1: ffffffff8f375b88 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x10a/0x1e0 net/smc/smc_pnet.c:878

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00212 11th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.215, 5.15.155, 6.1.86 +3Red Hat: 1 advisoryRed Hat: 5 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.10 and later5.10.215, 5.15.155, 6.1.86, 6.6.27, 6.8.6, 6.9Patch availableCNA
  • Linux VendorLinux Affected 5.10 and later Fixed in 5.10.215, 5.15.155, 6.1.86, 6.6.27, 6.8.6, 6.9 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 5.10.215; 5.11 to before 5.15.155; 5.16 to before 6.1.86; 6.2 to before 6.6.27; 6.7 to before 6.8.6VulnerableLinux
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.10.215; 5.11 to before 5.15.155; 5.16 to before 6.1.86; 6.2 to before 6.6.27; 6.7 to before 6.8.6 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.215, 5.15.155, 6.1.86, 6.6.27, 6.8.6, 6.9

Red Hat 1 advisory

  • RHSA-2025:6966 Released 2025-05-13 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-570.12.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.12.1.el9_6, kernel-64k-devel-5.14.0-570.12.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-570.12.1.el9_6, kernel-64k-5.14.0-570.12.1.el9_6, kernel-64k-core-5.14.0-570.12.1.el9_6 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-570.12.1.el9_6, libperf-5.14.0-570.12.1.el9_6
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-570.12.1.el9_6, kernel-rt-64k-5.14.0-570.12.1.el9_6, kernel-rt-64k-core-5.14.0-570.12.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-570.12.1.el9_6, kernel-rt-core-5.14.0-570.12.1.el9_6, kernel-rt-debug-5.14.0-570.12.1.el9_6 +11

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:6966
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-35934
  2. 2026-10-03 Alias added: GHSA-xvf2-5mhq-w7h6

References

Patch 6

Advisory 1

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences