s390: fix double free of GS and RI CBs on fork() failure
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 3 fixed, 4 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-415 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: s390: fix double free of GS and RI CBs on fork() failure The pointers for guarded storage and runtime instrumentation control blocks are stored in the thread_struct of the associated task. These pointers are initially copied on fork() via arch_dup_task_struct() and then cleared via copy_thread() before fork() returns. If fork() happens to fail after the initial task dup and before copy_thread(), the newly allocated task and associated thread_struct memory are freed via free_task() -> arch_release_task_struct(). This results in a double free of the guarded storage and runtime info structs because the fields in the failed task still refer to memory associated with the source task. This problem can manifest as a BUG_ON() in set_freepointer() (with CONFIG_SLAB_FREELIST_HARDENED enabled) or KASAN splat (if enabled) when running trinity syscall fuzz tests on s390x. To avoid this problem, clear the associated pointer fields in arch_dup_task_struct() immediately after the new task is copied. Note that the RI flag is still cleared in copy_thread() because it resides in thread stack memory and that is where stack info is copied.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.4.105 to before 4.5; 4.9.68 to before 4.10; 4.14.5 to before 4.15 | 4.5, 4.10, 4.15 | Patch available | CNA |
| Linux | Linux | 4.15 and later | 4.19.257, 5.4.212, 5.10.140, 5.15.64, 5.19.6, 6.0 | Patch available | CNA |
- Linux VendorLinux Affected 4.4.105 to before 4.5; 4.9.68 to before 4.10; 4.14.5 to before 4.15 Fixed in 4.5, 4.10, 4.15 Patch available CNA
- Linux VendorLinux Affected 4.15 and later Fixed in 4.19.257, 5.4.212, 5.10.140, 5.15.64, 5.19.6, 6.0 Patch available CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.4.105 to before 4.5; 4.9.68 to before 4.10; 4.14.5 to before 4.19.257; 4.20 to before 5.4.212; 5.5 to before 5.10.140; 5.11 to before 5.15.64; 5.16 to before 5.19.6 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:* | 6.0 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:* | 6.0 rc2 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.4.105 to before 4.5; 4.9.68 to before 4.10; 4.14.5 to before 4.19.257; 4.20 to before 5.4.212; 5.5 to before 5.10.140; 5.11 to before 5.15.64; 5.16 to before 5.19.6 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:* Versions 6.0 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:* Versions 6.0 rc2 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.5, 4.10, 4.15
- Fix · CNA Linux (Linux) Fixed in 4.19.257, 5.4.212, 5.10.140, 5.15.64, 5.19.6, 6.0
Red Hat 1 advisory
- RHSA-2023:2458 Released 2023-05-09 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-284.11.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.11.1.el9_2, kernel-64k-devel-5.14.0-284.11.1.el9_2 +10
- Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.0.0-284.11.1.el9_2, kernel-5.14.0-284.11.1.el9_2, kernel-64k-5.14.0-284.11.1.el9_2 +29
- Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-284.11.1.el9_2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2023:2458 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2023:2458 |
| Red Hat Enterprise Linux CRB (v. 9) | Fixed | RHSA-2023:2458 |
Not affected: 1 product
- Red Hat Enterprise Linux 10
Timeline
- 2026-10-02 Threatist record created from CVE-2022-49990
- 2026-10-03 Alias added: GHSA-8px8-fjv5-9vgx
- 2026-10-16 CISA SSVC decision points changed
References
Patch 6
- https://git.kernel.org/stable/c/25a95303b9e513cd2978aacc385d06e6fec23d07
- https://git.kernel.org/stable/c/cacd522e6652fbc2dc0cc6ae11c4e30782fef14b
- https://git.kernel.org/stable/c/297ae7e87a87a001dd3dfeac1cb26a42fd929708
- https://git.kernel.org/stable/c/8195e065abf3df84eb0ad2987e76a40f21d1791c
- https://git.kernel.org/stable/c/fbdc482d43eda40a70de4b0155843d5472f6de62
- https://git.kernel.org/stable/c/13cccafe0edcd03bf1c841de8ab8a1c8e34f77d9
More Linux Kernel vulnerabilities
- 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
Sources
- CVE-2022-49990 · CVE Program
- CVE-2022-49990 · NVD
- FIRST EPSS
- GHSA-8px8-fjv5-9vgx · GitHub Advisory Database · CC BY 4.0
- CVE-2022-49990 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences