CVE-2025-39742: RDMA: hfi1: fix possible divide-by-zero in find_hw_thread_mask()
In the Linux kernel, the following vulnerability has been resolved:
RDMA: hfi1: fix possible divide-by-zero in findhwthreadmask()
The function divides number of online CPUs by numcoresiblings, and later checks the divider by zero. This implies a possibility to get and divide-by-zero runtime error. Fix it by moving the check prior to division. This also helps to save one indentation level.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.113-1Fixed in 7.2.12-1Fixed in 7.2.13-1 - Compensating control
In the Linux kernel RDMA hfi1 function find_hw_thread_mask(), check whether num_core_siblings is zero before dividing the number of online CPUs by it.
Event History
Frequently Asked Questions
What is the severity of CVE-2025-39742?
CVE-2025-39742 has a severity rating that indicates a potential impact on system stability due to a divide-by-zero vulnerability in the Linux kernel.
How do I fix CVE-2025-39742?
To fix CVE-2025-39742, update your Linux kernel to the latest version where the vulnerability has been patched.
What systems are affected by CVE-2025-39742?
CVE-2025-39742 affects various versions of the Linux kernel that utilize the RDMA subsystem.
What does CVE-2025-39742 vulnerability entail?
CVE-2025-39742 involves a divide-by-zero error in the function find_hw_thread_mask() which may lead to unexpected behavior.
Is CVE-2025-39742 exploit-related to denial of service?
Yes, CVE-2025-39742 could potentially be exploited to cause a denial of service condition due to system crashes or instability.