CVE-2026-68435: LoongArch: Fix address space mismatch in kexec command line lookup
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Fix address space mismatch in kexec command line lookup
When searching the loaded segments for the "kexec" command line marker, the kexecload(2) path (filemode == 0) passes the user-space segment buffer straight to strncmp() through a bogus (char user ) cast. This dereferences a user pointer in kernel context, which is wrong and is flagged by sparse:
arch/loongarch/kernel/machinekexec.c:84:51: sparse: incorrect type in argument 2 (different address spaces) @@ expected char const @@ got char [noderef] user
Here copy the marker-sized prefix of each segment into a small on-stack buffer with copyfromuser() before comparing, and skip segments that fault. The subsequent copyfromuser() that stages the full command line into the safe area is left unchanged.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-68435?
The severity of CVE-2026-68435 has been rated as 34, indicating a medium risk level.
How do I fix CVE-2026-68435?
To fix CVE-2026-68435, ensure that your Linux kernel is updated to a version that includes the patch for this vulnerability.
What systems are affected by CVE-2026-68435?
CVE-2026-68435 affects the Linux kernel on systems utilizing the LoongArch architecture.
What does CVE-2026-68435 involve?
CVE-2026-68435 involves a fix for address space mismatch issues occurring during the kexec command line lookup.
Is CVE-2026-68435 a local or remote vulnerability?
CVE-2026-68435 is considered a local vulnerability as it involves user-space segment buffer access.