Fixed
Created: Jun 19, 2024
Updated: Jun 25, 2024
Resolved Date: Jun 24, 2024
Found In Version: 10.22.33.1
Fix Version: 10.22.33.17
Severity: Standard
Applicable for: Wind River Linux LTS 22
Component/s: Kernel
In the Linux kernel, the following vulnerability has been resolved:drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map()Patch series "mm: follow_pte() improvements and acrn follow_pte() fixes".Patch #1 fixes a bunch of issues I spotted in the acrn driver. Itcompiles, that's all I know. I'll appreciate some review and testing fromacrn folks.Patch #2+#3 improve follow_pte(), passing a VMA instead of the MM, addingmore sanity checks, and improving the documentation. Gave it a quick teston x86-64 using VM_PAT that ends up using follow_pte().This patch (of 3):We currently miss handling various cases, resulting in a dangerousfollow_pte() (previously follow_pfn()) usage.(1) We're not checking PTE write permissions.Maybe we should simply always require pte_write() like we do forpin_user_pages_fast(FOLL_WRITE)? Hard to tell, so let's check forACRN_MEM_ACCESS_WRITE for now.(2) We're not rejecting refcounted pages.As we are not using MMU notifiers, messing with refcounted pages isdangerous and can result in use-after-free. Let's make sure to reject them.(3) We are only looking at the first PTE of a bigger range.We only lookup a single PTE, but memmap->len may span a larger area.Let's loop over all involved PTEs and make sure the PFN range isactually contiguous. Reject everything else: it couldn't have workedeither way, and rather made use access PFNs we shouldn't be accessing.
CREATE(Triage):(User=admin) CVE-2024-38610 (https://nvd.nist.gov/vuln/detail/CVE-2024-38610)
