serial/pmac_zilog: Remove flawed mitigation for rx irq flood
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 4 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-667 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: serial/pmac_zilog: Remove flawed mitigation for rx irq flood The mitigation was intended to stop the irq completely. That may be better than a hard lock-up but it turns out that you get a crash anyway if you're using pmac_zilog as a serial console: ttyPZ0: pmz: rx irq flood ! BUG: spinlock recursion on CPU#0, swapper/0 That's because the pr_err() call in pmz_receive_chars() results in pmz_console_write() attempting to lock a spinlock already locked in pmz_interrupt(). With CONFIG_DEBUG_SPINLOCK=y, this produces a fatal BUG splat. The spinlock in question is the one in struct uart_port. Even when it's not fatal, the serial port rx function ceases to work. Also, the iteration limit doesn't play nicely with QEMU, as can be seen in the bug report linked below. A web search for other reports of the error message "pmz: rx irq flood" didn't produce anything. So I don't think this code is needed any more. Remove it.
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 | 2.6.12 and later | 4.19.313, 5.4.275, 5.10.216, 5.15.157, 6.1.88, 6.6.29, 6.8.8, 6.9 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.12 and later Fixed in 4.19.313, 5.4.275, 5.10.216, 5.15.157, 6.1.88, 6.6.29, 6.8.8, 6.9 Patch available CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.12 to before 5.15.157; 5.16 to before 6.1.88; 6.2 to before 6.6.29; 6.7 to before 6.8.8 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:* | 6.9 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:* | 6.9 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:* | 6.9 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.9:rc4:*:*:*:*:*:* | 6.9 rc4 | Vulnerable | Linux |
| cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Debian |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.12 to before 5.15.157; 5.16 to before 6.1.88; 6.2 to before 6.6.29; 6.7 to before 6.8.8 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:* Versions 6.9 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:* Versions 6.9 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:* Versions 6.9 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.9:rc4:*:*:*:*:*:* Versions 6.9 rc4 Vulnerable ·Linux
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.19.313, 5.4.275, 5.10.216, 5.15.157, 6.1.88, 6.6.29, 6.8.8, 6.9
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 planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Will not fix |
| Red Hat Enterprise Linux 9 | Affected | No fix planned: Will not fix |
Timeline
- 2026-10-02 Threatist record created from CVE-2024-26999
- 2026-10-03 Alias added: GHSA-hwgv-6mjr-cw48
References
Patch 8
- https://git.kernel.org/stable/c/69a02273e288011b521ee7c1f3ab2c23fda633ce
- https://git.kernel.org/stable/c/d679c816929d62af51c8e6d7fc0e165c9412d2f3
- https://git.kernel.org/stable/c/ab86cf6f8d24e63e9aca23da5108af1aa5483928
- https://git.kernel.org/stable/c/7a3bbe41efa55323b6ea3c35fa15941d4dbecdef
- https://git.kernel.org/stable/c/bbaafbb4651fede8d3c3881601ecaa4f834f9d3f
- https://git.kernel.org/stable/c/52aaf1ff14622a04148dbb9ccce6d9de5d534ea7
- https://git.kernel.org/stable/c/ca09dfc3cfdf89e6af3ac24e1c6c0be5c575a729
- https://git.kernel.org/stable/c/1be3226445362bfbf461c92a5bcdb1723f2e4907
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-2024-26999 · CVE Program
- CVE-2024-26999 · NVD
- FIRST EPSS
- GHSA-hwgv-6mjr-cw48 · GitHub Advisory Database · CC BY 4.0
- CVE-2024-26999 · 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