CVE-2026-98719: Linux

Описание

Оригинално описание

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Nullify "have run CPUs" mask pointer when freeing it Nullify have_run_cpus when freeing the mask, particularly in the error path of __sev_guest_init(), so that KVM doesn't have to subtly use sev->active to track whether or not the mask has been freed. As pointed out by Sashiko, blindly freeing the mask in sev_vm_destroy() results in a double-free if the mask is freed if __sev_guest_init() fails. Throw the logic in a helper as nullifying the pointer is frustratingly difficult and weird due to have_run_cpus being a single-entry array when CPUMASK_OFFSTACK=n. Deliberately don't use CPUMASK_VAR_NULL, as it's not directly assignable when the cpumask is on-stack, e.g. requires using a local variable and a memcpy(), which is beyond ridiculous. Furthermore, while clearing the on-stack bitmask is an unnecessary and arguably unwanted side effect, KVM absolutely relies on '0' being the "null" value given that the struct is zero-allocated. Opportunistically add an alloc() helper to pair with free(); there are just enough call sites to make doing so worthwhile.

Засегнати продукти

• Linux Linux: 6aef7cf800098749ff5d660222efaf6e01e98c09 преди b1de3ebf59507e0edacaa5cfa2225bc1869e1b63; 9784e5ca91b37b387f3f414af4340c54f7a63566 преди 0fbc7fec2242de6c3dcea6de55573c428e820173; 12c1f6e03f944e399bd2c88441dca5dc702b95a5 преди 8abbc76120a74bfba1851bd97528099d715e45c6
• Linux Linux: 6.18.55 преди 6.18.56; 7.2.9 преди 7.2.10

История

Други уязвимости в Linux Linux

• 8.1CVE-2026-99270
• 7.8CVE-2026-99269
• CVE-2026-99268
• CVE-2026-99266
• CVE-2026-99267

Първоизточници

• https://www.cve.org/CVERecord?id=CVE-2026-98719
• https://nvd.nist.gov/vuln/detail/CVE-2026-98719
• https://git.kernel.org/stable/c/b1de3ebf59507e0edacaa5cfa2225bc1869e1b63
• https://git.kernel.org/stable/c/0fbc7fec2242de6c3dcea6de55573c428e820173
• https://git.kernel.org/stable/c/8abbc76120a74bfba1851bd97528099d715e45c6