mm/debug_vm_pgtable: fix BUG_ON with pud advanced test
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
In the Linux kernel, the following vulnerability has been resolved: mm/debug_vm_pgtable: fix BUG_ON with pud advanced test Architectures like powerpc add debug checks to ensure we find only devmap PUD pte entries. These debug checks are only done with CONFIG_DEBUG_VM. This patch marks the ptes used for PUD advanced test devmap pte entries so that we don't hit on debug checks on architecture like ppc64 as below. WARNING: CPU: 2 PID: 1 at arch/powerpc/mm/book3s64/radix_pgtable.c:1382 radix__pud_hugepage_update+0x38/0x138 .... NIP [c0000000000a7004] radix__pud_hugepage_update+0x38/0x138 LR [c0000000000a77a8] radix__pudp_huge_get_and_clear+0x28/0x60 Call Trace: [c000000004a2f950] [c000000004a2f9a0] 0xc000000004a2f9a0 (unreliable) [c000000004a2f980] [000d34c100000000] 0xd34c100000000 [c000000004a2f9a0] [c00000000206ba98] pud_advanced_tests+0x118/0x334 [c000000004a2fa40] [c00000000206db34] debug_vm_pgtable+0xcbc/0x1c48 [c000000004a2fc10] [c00000000000fd28] do_one_initcall+0x60/0x388 Also kernel BUG at arch/powerpc/mm/book3s64/pgtable.c:202! .... NIP [c000000000096510] pudp_huge_get_and_clear_full+0x98/0x174 LR [c00000000206bb34] pud_advanced_tests+0x1b4/0x334 Call Trace: [c000000004a2f950] [000d34c100000000] 0xd34c100000000 (unreliable) [c000000004a2f9a0] [c00000000206bb34] pud_advanced_tests+0x1b4/0x334 [c000000004a2fa40] [c00000000206db34] debug_vm_pgtable+0xcbc/0x1c48 [c000000004a2fc10] [c00000000000fd28] do_one_initcall+0x60/0x388
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 | 6.6 and later | 6.6.21, 6.7.9, 6.8 | Patch available | CNA |
- Linux VendorLinux Affected 6.6 and later Fixed in 6.6.21, 6.7.9, 6.8 Patch available CNA
CPE configurations NVD · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.6 to before 6.6.21; 6.7 to before 6.7.9 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:* | 6.8 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:* | 6.8 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:* | 6.8 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:* | 6.8 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:* | 6.8 rc5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc6:*:*:*:*:*:* | 6.8 rc6 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.6 to before 6.6.21; 6.7 to before 6.7.9 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:* Versions 6.8 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:* Versions 6.8 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:* Versions 6.8 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:* Versions 6.8 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:* Versions 6.8 rc5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc6:*:*:*:*:*:* Versions 6.8 rc6 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.6.21, 6.7.9, 6.8
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-2024-26850
- 2026-10-03 Alias added: GHSA-cpf6-9p2g-chcq
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-2024-26850 · CVE Program
- CVE-2024-26850 · NVD
- FIRST EPSS
- GHSA-cpf6-9p2g-chcq · GitHub Advisory Database · CC BY 4.0
- CVE-2024-26850 · 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