Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: mm: hugetlb: fix UAF in hugetlb_handle_userfault The vma_lock and hugetlb_fault_mutex are dropped before handling userfault and reacquire them again after handle_userfault(), but reacquire the vma_lock could lead to UAF[1,2] due to the following race, hugetlb_fault hugetlb_no_page /*unlock vma_lock */ hugetlb_handle_userfault handle_userfault /* unlock mm->mmap_lock*/ vm_mmap_pgoff do_mmap mmap_region munmap_vma_range /* clean old vma */ /* lock vma_lock again <--- UAF */ /* unlock vma_lock */ Since the vma_lock will unlock immediately after hugetlb_handle_userfault(), let's drop the unneeded lock and unlock in hugetlb_handle_userfault() to fix the issue. [1] https://lore.kernel.org/linux-mm/[email protected]/ [2] https://lore.kernel.org/linux-mm/[email protected]/
References
- https://git.kernel.org/stable/c/0db2efb3bff879566f05341d94c3de00ac95c4cc
- https://git.kernel.org/stable/c/45c33966759ea1b4040c08dacda99ef623c0ca29
- https://git.kernel.org/stable/c/78504bcedb2f1bbfb353b4d233c24d641c4dda33
- https://git.kernel.org/stable/c/958f32ce832ba781ac20e11bb2d12a9352ea28fc
- https://git.kernel.org/stable/c/dd691973f67b2800a97db723b1ff6f07fdcf7f5a
FAQ
What is CVE-2022-50630?
CVE-2022-50630 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: mm: hugetlb: fix UAF in hugetlb_handle_userfault The vma_lock and hugetlb_fault_mutex are dropped before handling userfault and re...
How severe is CVE-2022-50630?
CVSS scoring is not yet available for CVE-2022-50630. Check NVD for updates.
Is there a patch for CVE-2022-50630?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.