CVE-2026-64167: kho: skip KHO for crash kernel
Greg Kroah-Hartman <[email protected]>
| Newsgroups | org.kernel.vger.linux-cve-announce |
|---|---|
| Message-ID | <2026071935-CVE-2026-64167-a168@gregkh> |
From: Greg Kroah-Hartman <[email protected]> Description =========== In the Linux kernel, the following vulnerability has been resolved: kho: skip KHO for crash kernel kho_fill_kimage() unconditionally populates the kimage with KHO metadata for every kexec image type. When the image is a crash kernel, this can be problematic as the crash kernel can run in a small reserved region and the KHO scratch areas can sit outside it. The crash kernel then faults during kho_memory_init() when it tries phys_to_virt() on the KHO FDT address: Unable to handle kernel paging request at virtual address xxxxxxxx ... fdt_offset_ptr+... fdt_check_node_offset_+... fdt_first_property_offset+... fdt_get_property_namelen_+... fdt_getprop+... kho_memory_init+... mm_core_init+... start_kernel+... kho_locate_mem_hole() already skips KHO logic for KEXEC_TYPE_CRASH images, but kho_fill_kimage() was missing the same guard. As kho_fill_kimage() is the single point that populates image->kho.fdt and image->kho.scratch, fixing it here is sufficient for both arm64 and x86 as the FDT and boot_params path are bailing out when these fields are unset. The Linux kernel CVE team has assigned CVE-2026-64167 to this issue. Affected and fixed versions =========================== Issue introduced in 6.19 with commit d7255959b69a4e727c61eb04231d11390d4f391e and fixed in 7.0.11 with commit a6ac6721326a75ff2d14c68db05f93b576d8762f Issue introduced in 6.19 with commit d7255959b69a4e727c61eb04231d11390d4f391e and fixed in 7.1 with commit a6715d7ec472a476db17787697a4abda62962284 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-64167 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: kernel/liveupdate/kexec_handover.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/a6ac6721326a75ff2d14c68db05f93b576d8762f https://git.kernel.org/stable/c/a6715d7ec472a476db17787697a4abda62962284