erofs: fix pcluster use-after-free on UP platforms
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
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: erofs: fix pcluster use-after-free on UP platforms During stress testing with CONFIG_SMP disabled, KASAN reports as below: ================================================================== BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30 Read of size 8 at addr ffff8881094223f8 by task stress/7789 CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 Call Trace: <TASK> .. __mutex_lock+0xe5/0xc30 .. z_erofs_do_read_page+0x8ce/0x1560 .. z_erofs_readahead+0x31c/0x580 .. Freed by task 7787 kasan_save_stack+0x1e/0x40 kasan_set_track+0x20/0x30 kasan_set_free_info+0x20/0x40 __kasan_slab_free+0x10c/0x190 kmem_cache_free+0xed/0x380 rcu_core+0x3d5/0xc90 __do_softirq+0x12d/0x389 Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0x97/0xb0 call_rcu+0x3d/0x3f0 erofs_shrink_workstation+0x11f/0x210 erofs_shrink_scan+0xdc/0x170 shrink_slab.constprop.0+0x296/0x530 drop_slab+0x1c/0x70 drop_caches_sysctl_handler+0x70/0x80 proc_sys_call_handler+0x20a/0x2f0 vfs_write+0x555/0x6c0 ksys_write+0xbe/0x160 do_syscall_64+0x3b/0x90 The root cause is that erofs_workgroup_unfreeze() doesn't reset to orig_val thus it causes a race that the pcluster reuses unexpectedly before freeing. Since UP platforms are quite rare now, such path becomes unnecessary. Let's drop such specific-designed path directly instead.
Why it matters now
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.19.26 to before 4.20; 4.20.13 to before 4.21 | 4.20, 4.21 | Patch available | CNA |
| Linux | Linux | 5.0 and later | 5.15.68, 5.19.9, 6.0 | Patch available | CNA |
- Linux VendorLinux Affected 4.19.26 to before 4.20; 4.20.13 to before 4.21 Fixed in 4.20, 4.21 Patch available CNA
- Linux VendorLinux Affected 5.0 and later Fixed in 5.15.68, 5.19.9, 6.0 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.19.26 to before 4.20; 4.20.13 to before 5.15.68; 5.16 to before 5.19.9 | 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:6.0:rc3:*:*:*:*:*:* | 6.0 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.0:rc4:*:*:*:*:*:* | 6.0 rc4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.19.26 to before 4.20; 4.20.13 to before 5.15.68; 5.16 to before 5.19.9 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
- cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:* Versions 6.0 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.0:rc4:*:*:*:*:*:* Versions 6.0 rc4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.20, 4.21
- Fix · CNA Linux (Linux) Fixed in 5.15.68, 5.19.9, 6.0
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2022-48674
- 2026-10-03 Alias added: GHSA-5cqc-m9rw-57r9
- 2026-11-07 Affected versions changed · Red Hat
References
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-2022-48674 · CVE Program
- CVE-2022-48674 · NVD
- FIRST EPSS
- GHSA-5cqc-m9rw-57r9 · GitHub Advisory Database · CC BY 4.0
- CVE-2022-48674 · 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