mm: hugetlb: fix UAF in hugetlb_handle_userfault
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 5.10.150, 5.15.75, 5.19.17, 6.0.3
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
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/000000000000d5e00a05e834962e@google.com/ [2] https://lore.kernel.org/linux-mm/20220921014457.1668-1-liuzixian4@huawei.com/
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 · fixed in 45c33966759ea1b4040c08dacda99ef623c0ca29; From 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 · fixed in 0db2efb3bff879566f05341d94c3de00ac95c4cc; From 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 · fixed in dd691973f67b2800a97db723b1ff6f07fdcf7f5a; From 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 · fixed in 78504bcedb2f1bbfb353b4d233c24d641c4dda33; From 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 · fixed in 958f32ce832ba781ac20e11bb2d12a9352ea28fc
- Linux Linux
4.11
- KernelLinux
From 4.11.0 · fixed in 5.10.150; From 5.11.0 · fixed in 5.15.75; From 5.16.0 · fixed in 5.19.17; From 5.20.0 · fixed in 6.0.3