Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previously registered with userfaultfd as write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in flag clearing leads to a mismatch between the vma flags (which have uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to trigger a warning in page_table_check_pte_flags() due to setting the pte to writable while uffd-wp is still set. Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any such mremap() so that the values are consistent with the existing clearing of VM_UFFD_WP. Be careful to clear the logical flag regardless of its physical form; a PTE bit, a swap PTE bit, or a PTE marker. Cover PTE, huge PMD and hugetlb paths.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 before 8e2f6ba256dd1e590addc48e6e9577bf39c482f2; affected 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 before 310ac886d68de661c3a334198d8604b722d7fdf8; affected 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 before 0cef0bb836e3cfe00f08f9606c72abd72fe78ca3 |
| Linux / Linux | affected 5.7; unaffected 0 before 5.7; unaffected 6.6.160 through 6.6.*; unaffected 6.12.11 through 6.12.*; unaffected 6.13 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/8e2f6ba256dd1e590addc48e6e9577bf39c482f2
- https://git.kernel.org/stable/c/310ac886d68de661c3a334198d8604b722d7fdf8
- https://git.kernel.org/stable/c/0cef0bb836e3cfe00f08f9606c72abd72fe78ca3
ADP enrichment
No English description supplied.
No references supplied.